MPLX LP, 10-K filed on 2/26/2026
Annual Report
v3.25.4
Document and Entity Information - USD ($)
$ in Billions
 12 Months Ended
Dec. 31, 2025
Feb. 20, 2026
Jun. 30, 2025
Cover [Abstract]      
Document Type 10-K    
Document Annual Report true    
Document Transition Report false    
Entity File Number 001-35714    
Entity Registrant Name MPLX LP    
Entity Incorporation, State or Country Code DE    
Entity Tax Identification Number 27-0005456    
Entity Address, Address Line One 200 E. Hardin Street    
Entity Address, City or Town Findlay    
Entity Address, State or Province OH    
Entity Address, Postal Zip Code 45840-3229    
City Area Code 419    
Local Phone Number 422-2121    
Title of 12(b) Security Common Units Representing Limited Partnership Interests    
Trading Symbol MPLX    
Security Exchange Name NYSE    
Entity Well-known Seasoned Issuer Yes    
Entity Voluntary Filers No    
Entity Current Reporting Status Yes    
Entity Interactive Data Current Yes    
Entity Filer Category Large Accelerated Filer    
Entity Small Business false    
Entity Emerging Growth Company false    
ICFR Auditor Attestation Flag true    
Document Financial Statement Error Correction [Flag] false    
Entity Shell Company false    
Entity Public Float     $ 19.1
Entity Common Stock, Shares Outstanding   1,015,204,337  
Amendment Flag false    
Document Fiscal Year Focus 2025    
Document Fiscal Period Focus FY    
Entity Central Index Key 0001552000    
Current Fiscal Year End Date --12-31    
Document Period End Date Dec. 31, 2025    
v3.25.4
Audit Information
 12 Months Ended
Dec. 31, 2025
Auditor Information [Abstract]  
Auditor Firm ID 238
Auditor Name PricewaterhouseCoopers LLP
Auditor Location Toledo, Ohio
v3.25.4
Consolidated Statements of Income - USD ($)
shares in Millions, $ in Millions
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Revenues and other income:      
Sales-type lease revenue $ 151 $ 136 $ 136
Sales-type lease revenue, related parties 448 475 500
Income from equity method investments 697 802 600
Total revenues and other income 12,998 11,933 11,281
Costs and expenses:      
Purchases - related parties 1,649 1,583 1,544
Depreciation and amortization 1,351 1,283 1,213
General and administrative expenses 446 427 379
Other taxes 137 131 131
Total costs and expenses 7,055 6,645 6,381
Income from operations 5,943 5,288 4,900
Net interest and other financial costs 983 921 923
Income before income taxes 4,960 4,367 3,977
Other Tax Expense (Benefit) 8 10 11
Net income 4,952 4,357 3,966
Less: Net income attributable to noncontrolling interests 40 40 38
Limited partners’ interest in net income attributable to MPLX LP $ 4,912 $ 4,290 $ 3,829
Net income attributable to MPLX LP per limited partner unit:      
Common - basic $ 4.82 $ 4.21 $ 3.80
Common - diluted $ 4.82 $ 4.21 $ 3.80
Weighted average limited partner units outstanding:      
Common - basic 1,019 1,016 1,001
Common - diluted 1,019 1,017 1,002
Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent [1] $ 4,912 $ 4,317 $ 3,928
Equity Interest in Acquiree, Remeasurement Gain 484 20 92
Nonrelated Party      
Revenues and other income:      
Rental Income 260 251 243
Sales-type lease revenue 151 136 136
Other Income 179 50 34
Costs and expenses:      
Rental cost of sales 80 82 82
Related Party      
Revenues and other income:      
Rental Income 889 853 822
Sales-type lease revenue, related parties 448 475 500
Other Income 164 157 121
Costs and expenses:      
Rental cost of sales 16 18 33
Service [Member]      
Revenues and other income:      
Revenue from Contract with Customer, Excluding Assessed Tax, Third parties 2,899 2,770 2,539
Revenue from Contract with Customer, Excluding Assessed Tax, Related Parties 4,393 4,180 3,985
Product [Member]      
Revenues and other income:      
Revenue from Contract with Customer, Excluding Assessed Tax, Third parties 2,002 1,657 1,665
Revenue from Contract with Customer, Excluding Assessed Tax, Related Parties 143 225 250
Oil and Gas, Refining and Marketing [Member]      
Costs and expenses:      
Cost of revenues (excludes items below) 1,561 1,560 1,401
Natural Gas, Midstream [Member]      
Costs and expenses:      
Purchased product costs 1,815 1,561 1,598
Service, Other [Member]      
Revenues and other income:      
Revenue from Contract with Customer, Excluding Assessed Tax, Third parties 289 357 294
Series A Preferred Stock [Member]      
Costs and expenses:      
Dividends, Preferred Stock 0 27 94
Series B Preferred Stock [Member]      
Costs and expenses:      
Dividends, Preferred Stock $ 0 $ 0 $ 5
[1] Allocation of net income attributable to MPLX LP assumes all earnings for the period have been distributed based on the distribution priorities applicable to the period.
v3.25.4
Consolidated Statements of Comprehensive Income Statement - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Statement of Comprehensive Income [Abstract]      
Net income $ 4,952 $ 4,357 $ 3,966
Other comprehensive income, net of tax:      
Remeasurements of pension and other postretirement benefits related to equity method investments, net of tax 8 1 4
Comprehensive income 4,960 4,358 3,970
Less comprehensive income attributable to:      
Noncontrolling interests 40 40 38
Comprehensive income attributable to MPLX LP $ 4,920 $ 4,318 $ 3,932
v3.25.4
Consolidated Balance Sheets - USD ($)
$ in Millions
Dec. 31, 2025
Dec. 31, 2024
Assets, Current [Abstract]    
Cash and cash equivalents $ 2,137 $ 1,519
Receivables, less allowance for expected credit loss 735 718
Inventories 172 180
Other current assets 51 29
Total current assets 3,994 3,276
Equity method investments 4,798 4,531
Property, plant and equipment, net 21,698 19,154
Intangibles, net 1,397 518
Goodwill 8,755 7,645
Right of use assets, net 276 273
Other noncurrent assets 1,125 994
Total assets 43,005 37,511
Liabilities, Current [Abstract]    
Accounts payable 108 147
Accrued liabilities 254 295
Accrued property, plant and equipment 438 208
Long-term debt due within one year 1,502 1,693
Accrued interest payable 354 244
Total current liabilities 3,249 3,235
Long-term deferred revenue 119 317
Long-term debt 24,151 19,255
Deferred income taxes 25 18
Long-term operating lease liabilities 217 217
Total liabilities 28,477 23,501
Commitments and contingencies (see Note 22)
Series A Preferred Units 0 203
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest [Abstract]    
Accumulated other comprehensive income (loss) 5 (3)
Total MPLX LP partners’ capital 14,301 13,576
Noncontrolling interests 227 231
Total equity 14,528 13,807
Total liabilities, preferred units and equity 43,005 37,511
Related Party    
Assets, Current [Abstract]    
Receivables, less allowance for expected credit loss 624 620
Current assets - related parties 899 830
Other current assets 1 1
Right of use assets, net 239 226
Noncurrent assets - related parties 962 1,120
Liabilities, Current [Abstract]    
Operating lease liabilities 2 2
Other Liabilities, Current 399 396
Other Long-term Liabilities 364 334
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest [Abstract]    
Limited Partners' Capital Account 4,845 4,257
Nonrelated Party    
Assets, Current [Abstract]    
Right of use assets, net 276 273
Liabilities, Current [Abstract]    
Operating lease liabilities 53 45
Other Liabilities, Current 141 207
Other Long-term Liabilities 352 125
Long-term operating lease liabilities 217 217
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest [Abstract]    
Limited Partners' Capital Account $ 9,451 $ 9,322
v3.25.4
Consolidated Balance Sheets (Parenthetical) - shares
Dec. 31, 2025
Dec. 31, 2024
Units outstanding 1,015,702,040 1,017,142,290
Series A Preferred Stock [Member]    
Series A preferred, Units Outstanding 0 6,000,000
Nonrelated Party | Common Unit-holders Public    
Units outstanding 368,000,000 370,000,000
Related Party    
Units outstanding 647,415,452  
Related Party | Common Unit-holders Public    
Units outstanding 647,000,000 647,000,000
v3.25.4
Consolidated Statements of Cash Flows - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Operating activities:      
Net income $ 4,952 $ 4,357 $ 3,966
Adjustments to reconcile net income to net cash provided by operating activities:      
Amortization of deferred financing costs and debt discount 30 54 55
Depreciation and amortization 1,351 1,283 1,213
Deferred income taxes 7 2 3
Gain on equity method investments (484) (20) (92)
(Gain)/loss on disposal of assets (161) 3 (14)
Income from equity method investments (697) (802) (600)
Distributions from unconsolidated affiliates 864 826 736
Change in fair value of derivatives (17) (3) 0
Changes in:      
Current receivables 48 180 14
Inventories (26) (20) (19)
Current liabilities and other current assets (12) 5 (17)
Assets and liabilities - related parties 126 84 84
Right of use assets and operating lease liabilities 3 (3) 0
Deferred revenue (74) (5) 107
All other, net (1) 5 (39)
Net cash provided by operating activities 5,909 5,946 5,397
Investing activities:      
Additions to property, plant and equipment (1,808) (1,056) (937)
Acquisitions, net of cash acquired (3,316) (622) (246)
Disposal of assets 975 1 26
Investments - acquisitions and contributions 1,008 464 98
Investments - redemptions, repayments, return of capital and sales proceeds 293 146 3
All other, net 8 0 0
Net cash used in investing activities (4,856) (1,995) (1,252)
Financing activities:      
Long-term debt borrowings 6,541 1,630 1,589
Long-term debt repayments 2,464 1,151 1,001
Debt issuance costs (63) (15) (15)
Unit repurchases [1] (400) (326) 0
Distributions to noncontrolling interests (44) (44) (41)
Distributions to LP unitholders (4,018) (3,559) (3,181)
Contributions from MPC 24 35 31
All other, net (5) (6) (2)
Net cash used in financing activities (435) (3,480) (3,335)
Net change in cash, cash equivalents and restricted cash 618 471 810
Cash, cash equivalents and restricted cash at beginning of period 1,519 1,048 238
Cash, cash equivalents and restricted cash at end of period 2,137 1,519 1,048
Revolving Credit Facility      
Financing activities:      
Related party debt borrowings 50 0 0
Related party debt repayments (50) 0 0
Series A Preferred Stock [Member]      
Financing activities:      
Distributions to Preferred Unitholders (6) (44) (94)
Series B Preferred Stock [Member]      
Financing activities:      
Redemption of Series B preferred units 0 0 (600)
Distributions to Preferred Unitholders $ 0 $ 0 $ (21)
[1] Cash paid for common units repurchased and average cost per unit includes commissions paid to brokers during the period.
v3.25.4
Consolidated Statements of Equity and Series A Preferred Units (Consolidated Statements of Equity) - USD ($)
$ in Millions
Total
Common Unit-holders Public
Common Unit-holder MPC
Series B Preferred Unit-holders
Accumulated Other Comprehensive Income (Loss)
Non-controlling Interests
Beginning Balance at Dec. 31, 2022 $ 12,546 $ 8,413 $ 3,293 $ 611 $ (8) $ 237
Increase (Decrease) in Stockholders' Equity [Roll Forward]            
Net income 3,872 1,336 2,493 5 0 38
Conversion of Series A preferred units 73 73 0 0 0 0
Partners' Capital Account, Redemptions 600 2 3 595 0 0
Distributions (3,243) (1,125) (2,056) (21) 0  
Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders           (41)
Contributions 31 0 31 0 0 0
Other 10 5 0 0 4 1
Ending Balance at Dec. 31, 2023 12,689 8,700 3,758 0 (4) 235
Increase (Decrease) in Stockholders' Equity [Roll Forward]            
Net income 4,330 1,555 2,735 0 0 40
Unit repurchases (326) (326) 0 0 0 0
Conversion of Series A preferred units (675) (675) 0 0 0 0
Distributions (3,603) (1,289) (2,270) 0 0  
Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders           (44)
Contributions 34 0 34 0 0 0
Other 8 7 0 0 1 0
Ending Balance at Dec. 31, 2024 13,807 9,322 4,257 0 (3) 231
Increase (Decrease) in Stockholders' Equity [Roll Forward]            
Net income 4,952 1,791 3,121 0 0 40
Unit repurchases (400) (400) 0 0 0 0
Conversion of Series A preferred units 197 197 0 0 0 0
Distributions (4,062) (1,463) (2,555) 0 0  
Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders           (44)
Contributions 21 0 21 0 0 0
Other 13 4 1 0 8 0
Ending Balance at Dec. 31, 2025 $ 14,528 $ 9,451 $ 4,845 $ 0 $ 5 $ 227
v3.25.4
Consolidated Statements of Equity and Series A Preferred Units (Temporary Equity) - USD ($)
$ in Millions
Total
Series A Preferred Unit-holders
Beginning Balance at Dec. 31, 2022   $ 968
Increase (Decrease) in Temporary Equity [Roll Forward]    
Net income   94
Conversion of Series A preferred units   (73)
Distributions   94
Ending Balance at Dec. 31, 2023   895
Increase (Decrease) in Temporary Equity [Roll Forward]    
Net income   27
Conversion of Series A preferred units   675
Distributions   44
Ending Balance at Dec. 31, 2024 $ 203 203
Increase (Decrease) in Temporary Equity [Roll Forward]    
Net income   0
Conversion of Series A preferred units   197
Distributions   6
Ending Balance at Dec. 31, 2025 $ 0 $ 0
v3.25.4
Description of Business and Basis of Presentation
 12 Months Ended
Dec. 31, 2025
Limited Liability Company or Limited Partnership, Business Organization and Operations [Abstract]  
Business Description and Basis of Presentation [Text Block] Description of the Business and Basis of Presentation
Description of the Business
MPLX LP is a diversified, large-cap master limited partnership formed by Marathon Petroleum Corporation that owns and operates midstream energy infrastructure and logistics assets, and provides fuels distribution services. References in this report to “MPLX LP,” “MPLX,” “the Partnership,” “us,” “our,” “we,” or like terms refer to MPLX LP and its consolidated subsidiaries. References to our sponsor and customer, “MPC,” refer collectively to Marathon Petroleum Corporation and its subsidiaries, other than the Partnership. We are engaged in the gathering, transportation, storage and distribution of crude oil, refined products, other hydrocarbon-based products and renewables; the gathering, treating, processing and transportation of natural gas; and the transportation, fractionation, storage and marketing of NGLs. MPLX’s principal executive office is located in Findlay, Ohio. MPLX was formed on March 27, 2012 as a Delaware limited partnership.
Refer to Note 10 for additional information about our operations.
Basis of Presentation
The accompanying consolidated financial statements of MPLX have been prepared in accordance with GAAP. The consolidated financial statements include all majority-owned and controlled subsidiaries. For non-wholly-owned consolidated subsidiaries, the interests owned by third parties have been recorded as Noncontrolling interests on the accompanying Consolidated Balance Sheets. Intercompany accounts and transactions have been eliminated. MPLX’s investments in which MPLX exercises significant influence but does not control and does not have a controlling financial interest are accounted for using the equity method. MPLX’s investments in VIEs, in which MPLX exercises significant influence but does not control and is not the primary beneficiary, are also accounted for using the equity method.
In the fourth quarter of 2024, we renamed and modified the composition of our segments to better reflect the product-based value chains and growth strategy of MPLX’s operations. Certain prior period financial statement amounts have been reclassified to conform to current period presentation.
v3.25.4
Summary of Principal Accounting Policies
 12 Months Ended
Dec. 31, 2025
Accounting Policies [Abstract]  
Significant Accounting Policies [Text Block] Summary of Principal Accounting Policies
Use of Estimates
The preparation of financial statements in accordance with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities as of the date of the consolidated financial statements and the reported amounts of revenues and expenses during the respective reporting periods. Actual results could differ materially from those estimates. Estimates are subject to uncertainties due to the levels of subjectivity and judgment necessary to account for highly uncertain matters or the susceptibility of such matters to change and affect items such as valuing identified intangible assets; determining the fair value of derivative instruments; evaluating impairments of long-lived assets, goodwill and equity investments; establishing estimated useful lives for long-lived assets; acquisition accounting; estimating revenues, expense accruals and capital expenditures; valuing AROs; recognizing share-based compensation expense; and determining liabilities, if any, for environmental and legal contingencies.
Revenue Recognition
Revenue is measured based on consideration specified in a contract with a customer. MPLX recognizes revenue when it satisfies a performance obligation by transferring control over a product or providing services to a customer.
MPLX enters into a variety of contract types in order to generate Product sales and Service revenue. MPLX provides services under the following types of arrangements:
•Fee-based arrangements – Under fee-based arrangements, MPLX receives fees for the following services: gathering, treating, processing and transportation of natural gas; transportation, fractionation, exchange and storage of NGLs; and transportation, terminalling, storage and distribution of crude oil, refined products, other hydrocarbon-based products, and renewables. The revenue MPLX earns from these arrangements is generally directly related to the volume of natural gas, NGLs, refined products or crude oil that is handled by or flows through MPLX’s systems and facilities and is not normally directly dependent on commodity prices. In certain cases, MPLX’s arrangements provide for minimum volume commitments. Fee-based arrangements are reported as Service revenue on the Consolidated Statements of Income. Revenue is recognized over time as services are performed. In certain instances when specifically stated in the contract terms, MPLX purchases product after fee-based services have been provided. Revenue from the sale of products purchased after services are provided is reported as Product sales on the Consolidated Statements of Income and recognized on a gross basis, as MPLX takes control of the product and is the principal in the transaction.
•Percent-of-proceeds arrangements – Under percent-of-proceeds arrangements, MPLX gathers and processes natural gas on behalf of producers; sells the resulting residue gas, condensate and NGLs at market prices; and remits to producers an agreed-upon percentage of the proceeds. In other cases, instead of remitting cash payments to the
producer, MPLX delivers an agreed-upon percentage of the residue gas and NGLs to the producer (take-in-kind arrangements) and sells the volumes MPLX retains to third parties or related parties. Revenue is recognized on a net basis when MPLX acts as an agent and does not have control of the gross amount of gas and/or NGLs prior to it being sold. Percent-of-proceeds revenue is reported as Service revenue - product related on the Consolidated Statements of Income.
•Keep-whole arrangements – Under keep-whole arrangements, MPLX gathers natural gas from the producer, processes the natural gas and sells the resulting condensate and NGLs to third parties at market prices. Because the extraction of the condensate and NGLs from the natural gas during processing reduces the Btu content of the natural gas, MPLX must either purchase natural gas at market prices for return to producers or make cash payment to the producers equal to the value of the energy content of this natural gas. Certain keep-whole arrangements also have provisions that require MPLX to share a percentage of the keep-whole profits with the producers based on the oil to gas ratio or the NGL to gas ratio. Service revenue - product related is recorded based on the value of the NGLs received on the date the services are performed. Natural gas purchased to return to the producer and shared NGL profits are recorded as a reduction of Service revenue - product related on the Consolidated Statements of Income on the date the services are performed. Sales of NGLs under these arrangements are reported as Product sales on the Consolidated Statements of Income and are reported on a gross basis as MPLX is the principal in the arrangement and controls the product prior to sale. The sale of the NGLs may occur shortly after services are performed at the tailgate of the plant, or after a period of time as determined by MPLX.
•Purchase arrangements – Under purchase arrangements, MPLX purchases natural gas at either the wellhead or the tailgate of a plant. MPLX then gathers and delivers the natural gas to pipelines where MPLX may resell the natural gas. Wellhead purchase arrangements represent an arrangement with a supplier and are recorded in Purchased product costs. Often, MPLX earns fees for services performed prior to taking control of the product in these arrangements and Service revenue is recorded for these fees. Revenue generated from the sale of product obtained in tailgate purchase arrangements is reported as Product sales on the Consolidated Statements of Income and is recognized on a gross basis as MPLX purchases and takes control of the product prior to sale and is the principal in the transaction.
In many cases, MPLX provides services under contracts that contain a combination of more than one of the arrangements described above. When fees are charged (in addition to product received) under percent-of-proceeds arrangements, keep-whole arrangements or purchase arrangements, MPLX records such fees as Service revenue on the Consolidated Statements of Income. The terms of MPLX’s contracts vary based on gas quality conditions, the competitive environment when the contracts are signed, and customer requirements. Performance obligations are determined based on the specific terms of the arrangements, economics of the geographical regions, and the services offered and whether they are deemed distinct. MPLX allocates the consideration earned between the performance obligations based on the stand-alone selling price when multiple performance obligations are identified.
Revenue from MPLX’s service arrangements will generally be recognized over time as the performance obligation is satisfied as services are provided. MPLX has elected to use the output measure of progress to recognize revenue based on the units delivered, processed or transported. The transaction price may have fixed components related to minimum volume commitments and variable components, which are primarily dependent on volumes. Variable consideration will generally not be estimated at contract inception as the transaction price is specifically allocable to the services provided each period. In instances in which tiered pricing structures do not reflect our efforts to perform, MPLX will estimate variable consideration at contract inception. Product sales will be recognized at a point in time when control of the product transfers to the customer.
Minimum volume commitments may create contract liabilities if current period payments can be used for future services. If a customer fails to meet its minimum committed volumes, it owes MPLX a deficiency payment based on the terms of the applicable agreement. The deficiency amounts received under these agreements (excluding payments received under agreements classified as sales-type leases) are recorded as Current liabilities or Current liabilities - related parties. In many cases, the customer may then apply the amount of any such deficiency payments as a credit for volumes in excess of its minimum volume commitment in future periods under the terms of the applicable agreements. MPLX recognizes revenue for the deficiency payments when credits are used for volumes in excess of minimum quarterly volume commitments, where it is probable the customer will not use the credit in future periods or upon the expiration of the credits. The use or expiration of the credits is a decrease in Current liabilities or Current liabilities - related parties. Deficiency payments under agreements that have been classified as sales-type leases are recorded as a reduction against the corresponding lease receivable.
Amounts billed to customers for shipping and handling, electricity, and other costs to perform services are included in the transaction price as a component of Revenues and other income on the Consolidated Statements of Income. Shipping and handling costs associated with product sales are included in Purchased product costs on the Consolidated Statements of Income.
Customers usually pay monthly based on the products purchased or services performed that month. Taxes collected from customers and remitted to the appropriate taxing authority are excluded from revenue.
Based on the terms of certain contracts, MPLX is considered to be the lessor under several implicit operating and sales-type lease arrangements in accordance with GAAP. Revenue and costs related to the portion of the revenue earned under these contracts considered to be implicit operating leases are recorded as Rental income and Rental cost of sales, respectively, on the Consolidated Statements of Income. Revenue related to the portion of the revenue earned under these contracts considered to
be implicit sales-type lease arrangements is recorded as Sales-type lease revenue on the Consolidated Statements of Income, while related costs are recorded to Cost of revenues or Purchases - related parties.
Revenue and Expense Accruals
MPLX routinely makes accruals based on estimates for both revenues and expenses due to the timing of compiling billing information, receiving certain third-party information and reconciling MPLX’s records with those of third parties. The delayed information from third parties includes, among other things, actual volumes purchased, transported or sold, adjustments to inventory and invoices for purchases, actual natural gas and NGL deliveries, and other operating expenses. MPLX makes accruals to reflect estimates for these items based on its internal records and information from third parties. Estimated accruals are adjusted when actual information is received from third parties and MPLX’s internal records have been reconciled.
Other Taxes
Other taxes primarily include real estate taxes.
Cash and Cash Equivalents
Cash and cash equivalents include cash on hand and on deposit and investments in highly liquid debt instruments with original maturities of three months or less.
Receivables
Our receivables primarily consist of customer accounts receivable, which are recorded at the invoiced amounts and generally do not bear interest. Allowances for expected credit losses are estimated upon initial recognition of the receivables and updated each reporting period based on historical loss experience, current conditions and reasonable and supportable forecasts of future economic conditions. The allowance represents management’s best estimate of expected credit losses over the life of the receivables. We review the allowance quarterly and adjust as necessary for changes in risk factors and economic conditions. Past-due balances over 150 days are reviewed individually for collectability. Receivables deemed uncollectible are written off against the allowance, and recoveries are recognized when received.
Leases
Contracts with a term greater than one year that convey the right to direct the use of and obtain substantially all of the economic benefit of an asset are accounted for as right of use (“ROU”) assets and lease liabilities.
ROU asset and lease liability balances are recorded at the commencement date at present value of the fixed lease payments using a secured incremental borrowing rate with a maturity similar to the lease term because our leases do not provide implicit rates. We have elected to include both lease and non-lease components in the present value of the lease payments for all lessee asset classes with the exception of our marine and third-party contractor service and equipment leases. The lease component of the payment for the marine and equipment asset classes is determined using a relative standalone selling price. Operating lease expense is recognized on a straight-line basis over the lease term. See Note 21 for additional disclosures about our lease contracts.
As a lessor under ASC 842, MPLX may be required to re-classify existing operating leases to sales-type leases upon modification and related reassessment of the leases. See Note 21 for further information regarding our ongoing evaluation of the impacts of lease reassessments as modifications occur. The net investment in sales-type leases with third parties is recorded within Receivables, less allowance for expected credit loss and Other noncurrent assets on the Consolidated Balance Sheets. The net investment in sales-type leases with related parties is recorded within Current assets - related parties and Noncurrent assets - related parties on the Consolidated Balance Sheets. These amounts are comprised of the present value of the sum of the future minimum lease payments representing the value of the lease receivable and the unguaranteed residual value of the leased assets. Management assesses the net investment in sales-type leases for recoverability quarterly.
Inventories
Inventories consist of materials and supplies to be used in operations, line fill and other NGLs. Cost for materials and supplies are determined primarily using the weighted-average cost method. Inventories are valued at the lower of cost or net realizable value.
Imbalances
Within our pipelines and storage assets, we experience volume gains and losses due to pressure and temperature changes, evaporation and variances in meter readings and other measurement methods. Until settled, positive imbalances are recorded as other current assets and negative imbalances are recorded as accounts payable. Positive and negative imbalances are settled in cash, settled by physical delivery of volumes from a different source, or tracked and settled in the future.
Investment in Unconsolidated Affiliates
Equity investments in which MPLX exercises significant influence but does not control and is not the primary beneficiary, are accounted for using the equity method and are reported in Equity method investments on the accompanying Consolidated
Balance Sheets. This includes entities in which we hold majority ownership, but the minority shareholders have substantive participating rights. Differences in the basis of the investments and the separate net asset values of the investees, if any, are amortized into net income over the remaining useful lives of the underlying assets and liabilities, except for the excess related to goodwill.
Regular evaluation of these investments is appropriate to evaluate any potential need for impairment. MPLX uses evidence of a loss in value to identify if an investment has an other than a temporary decline. Impairments are recorded through Income from equity method investments.
Variable Interest Entities
We evaluate all legal entities in which we hold an ownership or other pecuniary interest to determine if the entity is a VIE. Our interests in a VIE are referred to as variable interests. Variable interests can be contractual, ownership or other pecuniary interests in an entity that change with changes in the fair value of the VIE’s assets. When we conclude that we hold an interest in a VIE, we must determine if we are the entity’s primary beneficiary. A primary beneficiary is deemed to have a controlling financial interest in a VIE. This controlling financial interest is evidenced by both (i) the power to direct the activities of the VIE that most significantly impact the VIE’s economic performance and (ii) the obligation to absorb losses that could potentially be significant to the VIE or the right to receive benefits that could potentially be significant to the VIE. We consolidate any VIE when we determine that we are the primary beneficiary. We must disclose the nature of any interests in a VIE that is not consolidated.
Significant judgment is exercised in determining that a legal entity is a VIE and in evaluating our interest in a VIE. We use primarily a qualitative analysis to determine if an entity is a VIE. We evaluate the entity’s need for continuing financial support; the equity holder’s lack of a controlling financial interest; and/or if an equity holder’s voting interests are disproportionate to its obligation to absorb expected losses or receive residual returns. We evaluate our interests in a VIE to determine whether we are the primary beneficiary. We use a primarily qualitative analysis to determine if we are deemed to have a controlling financial interest in the VIE, either on a standalone basis or as part of a related party group. We continually monitor our interests in legal entities for changes in the design or activities of an entity and changes in our interests, including our status as the primary beneficiary to determine if the changes require us to revise our previous conclusions.
Changes in the design or nature of the activities of a VIE, or our involvement with a VIE, may require us to reconsider our conclusions on the entity’s status as a VIE and/or our status as the primary beneficiary. Such reconsideration requires significant judgment and understanding of the organization. This could result in the deconsolidation or consolidation of the affected subsidiary, which would have a significant impact on our financial statements.
See Note 5 for additional disclosures about our VIEs.
Property, Plant and Equipment
Property, plant and equipment are recorded at cost and depreciated on a straight-line basis over the estimated useful lives of the assets. Expenditures that extend the useful lives of assets are capitalized.
Long-lived assets used in operations are assessed for impairment whenever changes in facts and circumstances indicate that the carrying value of the assets may not be recoverable based on the expected undiscounted future cash flows of an asset group. For purposes of impairment evaluation, long-lived assets must be grouped at the lowest level for which independent cash flows can be identified, which is at least at the reporting unit level and in some cases for similar assets in the same geographic region where cash flows can be separately identified. If the sum of the undiscounted future cash flows from the use of the asset group and its eventual disposition is less than the carrying value of an asset group, an impairment assessment is performed and the excess of the book value over the fair value is recorded as an impairment loss.
When items of property, plant and equipment are sold or otherwise disposed of, any gains or losses are reported on the Consolidated Statements of Income. Gains on the disposal of property, plant and equipment are recognized when earned, which is generally at the time of closing. If a loss on disposal is expected, such losses are recognized when the assets are classified as held for sale.
Interest costs for the construction or development of long-lived assets are capitalized and amortized over the related asset’s estimated useful life.
Goodwill and Intangibles
Goodwill represents the excess of the purchase price over the estimated fair value of the net assets acquired in the acquisition of a business. Goodwill is not amortized, but rather is tested for impairment at the reporting unit level annually and when events or changes in circumstances indicate that the fair value of a reporting unit with goodwill has been reduced below carrying value. If we determine, based on a qualitative assessment, that it is more likely than not that a reporting unit’s fair value exceeds its carrying amount, no further impairment testing is required. If we do not perform a qualitative assessment or if that assessment indicates that further impairment testing is required, the fair value of each reporting unit is determined using an income and market approach which is compared to the carrying value of the reporting unit. If the carrying amount of the reporting unit exceeds its fair value, an impairment loss would be recognized in an amount equal to that excess, limited to the total amount of goodwill allocated to that reporting unit. The fair value under the income approach is calculated using the expected present value
of future cash flows method. Significant assumptions used in the cash flow forecasts include future volumes, discount rates, and future capital requirements. See Note 14 for further details.
Amortization of intangibles with definite lives is calculated using the straight-line method, which is reflective of the benefit pattern in which the estimated economic benefit is expected to be received over the estimated useful life of the intangible asset. Intangibles subject to amortization are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of the intangible may not be recoverable. If the sum of the expected undiscounted future cash flows related to the asset is less than the carrying amount of the asset, an impairment loss is recognized based on the fair value of the asset.
Environmental Costs
Environmental expenditures for additional equipment that mitigates or prevents future contamination or improves environmental safety or efficiency of the existing assets are capitalized. We recognize remediation costs and penalties when the responsibility to remediate is probable and the amount of associated costs can be reasonably estimated. The timing of remediation accruals coincides with the completion of a feasibility study or the commitment to a formal plan of action. Remediation liabilities are accrued based on estimates of known environmental exposure and are discounted when the estimated amounts are reasonably fixed and determinable. If recoveries of remediation costs from third parties are probable, a receivable is recorded and is discounted when the estimated amount is reasonably fixed and determinable.
Asset Retirement Obligations
An ARO is a legal obligation associated with the retirement of tangible long-lived assets that generally result from the acquisition, construction, development or normal operation of the asset. The fair value of AROs is recognized in the period in which the obligations are incurred, if a reasonable estimate of fair value can be made, and added to the carrying amount of the associated asset. This additional carrying amount is then depreciated over the life of the asset. The liability is determined using a credit adjusted risk free interest rate and increases due to the passage of time based on the time value of money until the obligation is settled. AROs have not been recognized for certain assets because the fair value cannot be reasonably estimated since the settlement dates of the obligations are indeterminate. Such obligations will be recognized in the period when sufficient information becomes available to estimate a range of potential settlement dates. As of December 31, 2025 and 2024, MPLX’s asset retirement obligation was $45 million and $41 million, respectively, and is included on the balance sheet within Other long-term liabilities.
Derivative Instruments
MPLX may use commodity derivatives to economically hedge a portion of its exposure to commodity price risk. All derivative instruments (including derivatives embedded in other contracts) are recorded at fair value. MPLX discloses the fair value of all derivative instruments under the captions Other current assets, Other noncurrent assets, Other current liabilities and Other long-term liabilities on the Consolidated Balance Sheets. Certain commodity derivative positions may be governed by master netting arrangements and reflected on the consolidated balance sheets on a net basis by counterparty. MPLX did not utilize any commodity derivatives during the years ended December 31, 2025 or 2024. We make a distinction between realized or unrealized gains and losses on derivatives. During the period when a derivative contract is outstanding, changes in the fair value of the derivative are recorded as an unrealized gain or loss. When a derivative contract matures or is settled, the previously recorded unrealized gain or loss is reversed, and the realized gain or loss of the contract is recorded. Changes in the fair value of derivative instruments are reported on the Consolidated Statements of Income in accounts related to the item whose value or cash flows are being managed. Derivative instruments are marked to market through Product sales and Purchased product costs on the Consolidated Statements of Income.
During the years ended December 31, 2025, 2024 and 2023, MPLX did not elect hedge accounting for any derivatives. MPLX has historically elected the normal purchases and normal sales designation for certain contracts related to the physical purchase of electric power and the sale of most commodities.
Fair Value Measurement
Financial assets and liabilities recorded at fair value in the Consolidated Balance Sheets are categorized based upon the fair value hierarchy established by GAAP, which classifies the inputs used to measure fair value into Level 1, Level 2 or Level 3. A financial instrument’s categorization within the valuation hierarchy is based upon the lowest level of input that is significant to the fair value measurement. The methods and assumptions utilized may produce a fair value that may not be realized in future periods upon settlement. Furthermore, while MPLX believes its valuation methods are appropriate and consistent with other market participants, the use of different methodologies or assumptions to determine the fair value of certain financial instruments could result in a different estimate of fair value at the reporting date. For further discussion, see Note 15.
Equity-Based Compensation Arrangements
MPLX issues phantom units under the MPLX LP 2018 Incentive Compensation Plan. A phantom unit entitles the grantee a right to receive a common unit upon the issuance of the phantom unit. The fair value of phantom unit awards granted to employees and non-management directors is based on the fair market value of MPLX LP common units on the date of grant. The fair value of the units awarded is amortized into earnings using a straight-line amortization schedule over the period of service
corresponding with the vesting period. For phantom units that vest immediately and are not forfeitable, equity-based compensation expense is recognized at the time of grant.
To satisfy common unit awards, MPLX may issue new common units, acquire common units in the open market or use common units already owned by the general partner.
Income Taxes
MPLX is not a taxable entity for United States federal income tax purposes or for the majority of the states that impose an income tax. Taxes on MPLX’s net income generally are borne by its partners through the allocation of taxable income. MPLX’s taxable income or loss, which may vary substantially from the net income or loss reported on the Consolidated Statements of Income, is includable in the federal income tax returns of each partner. MPLX and certain legal entities are, however, taxable entities under certain state jurisdictions.
MPLX accounts for income taxes under the asset and liability method. Deferred income taxes are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax basis, capital loss carryforwards and net operating loss and credit carryforwards. Deferred tax assets and liabilities are measured using enacted tax rates applied to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect of any tax rate change on deferred taxes is recognized as tax expense/(benefit) from continuing operations in the period that includes the enactment date of the tax rate change. Realizability of deferred tax assets is assessed and, if not more likely than not, a valuation allowance is recorded to reflect the deferred tax assets at net realizable value as determined by management. All deferred tax balances are classified as long-term in the accompanying Consolidated Balance Sheets. All changes in the tax bases of assets and liabilities are allocated among operations and items charged or credited directly to equity.
Distributions
In preparing the Consolidated Statements of Equity, net income attributable to MPLX LP is allocated to preferred unitholders based on a fixed distribution schedule, as discussed in Notes 7 and 9, and subsequently allocated to the limited partner unitholders. Distributions are not accrued until declared. The allocation of net income attributable to MPLX LP for purposes of calculating net income per limited partner unit is described below.
Net Income Per Limited Partner Unit
MPLX uses the two-class method when calculating the net income per unit applicable to limited partners, because there is more than one class of participating security. The classes of participating securities include common units, preferred units and certain equity-based compensation awards.
Net income attributable to MPLX LP is allocated to the unitholders differently for preparation of the Consolidated Statements of Equity and the calculation of net income per limited partner unit. In preparing the Consolidated Statements of Equity, net income attributable to MPLX LP is allocated to preferred unitholders based on a fixed distribution schedule and subsequently allocated to remaining unitholders in accordance with their respective ownership percentages. The allocation of net income attributable to MPLX LP for purposes of calculating net income per limited partner unit is described in Note 8.
In preparing net income per limited partner units, during periods in which a net loss attributable to MPLX is reported or periods in which the total distributions exceed the reported net income attributable to MPLX’s unitholders, the amount allocable to certain equity-based compensation awards is based on actual distributions to the equity-based compensation awards. Diluted earnings per unit is calculated by dividing net income attributable to MPLX’s common unitholders, after deducting amounts allocable to other participating securities, by the weighted average number of common units and potential common units outstanding during the period. Potential common units are excluded from the calculation of diluted earnings per unit during periods in which net income attributable to MPLX’s unitholders, after deducting amounts that are allocable to the outstanding equity-based compensation awards and preferred units, is a loss, as the impact would be anti-dilutive.
Business Combinations
We recognize and measure the assets acquired and liabilities assumed in a business combination based on their estimated fair values at the acquisition date. Any excess or deficit of the purchase consideration when compared to the fair value of the net tangible assets acquired, if any, is recorded as goodwill or gain from a bargain purchase. Depending on the nature of the transaction, management may engage an independent valuation specialist to assist with the determination of fair value of the assets acquired, liabilities assumed, noncontrolling interests, if any, and goodwill, based on recognized business valuation methodologies. An income, market or cost valuation method may be utilized to estimate the fair value of the assets acquired, liabilities assumed, and noncontrolling interests, if any, in a business combination. The income valuation method represents the present value of future cash flows over the life of the asset using: (i) discrete financial forecasts, which rely on management’s estimates of volumes, certain commodity prices, revenue and operating expenses; (ii) long-term growth rates; and (iii) appropriate discount rates. The market valuation method uses prices paid for a reasonably similar asset by other purchasers in the market, with adjustments relating to any differences between the assets. The cost valuation method is based on the replacement cost of a comparable asset at prices at the time of the acquisition reduced for depreciation of the asset. If the initial accounting for the business combination is incomplete by the end of the reporting period in which the acquisition occurs, an
estimate will be recorded. Subsequent to the acquisition, and not later than one year from the acquisition date, MPLX will record any material adjustments to the initial estimate based on new information obtained that would have existed as of the acquisition date. Any adjustment that arises from information obtained that did not exist as of the date of the acquisition will be recorded in the period of the adjustment. Acquisition-related costs are expensed as incurred in connection with each business combination.
Acquisitions in which the company or business being acquired by MPLX had an existing relationship with MPC may result in the transaction being considered a transfer between entities under common control. In these situations, MPLX records the assets acquired and liabilities assumed on its consolidated balance sheets at MPC’s historical carrying value. For the acquiring entity, transfers of businesses between entities under common control require prior periods to be retrospectively adjusted for those dates that the entity was under common control.
v3.25.4
Accounting Standards
 12 Months Ended
Dec. 31, 2025
Accounting Standards Update and Change in Accounting Principle [Abstract]  
Accounting Standards Accounting Standards
Not Yet Adopted
ASU 2024-03, Income Statement – Reporting Comprehensive Income – Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses
In November 2024, the FASB issued an ASU to require more detailed information about specified categories of expenses (purchases of inventory, employee compensation, depreciation, amortization, and depletion) included in certain expense captions presented on the face of the income statement. This ASU is effective for fiscal years beginning after December 15, 2026, and for interim periods within fiscal years beginning after December 15, 2027. Early adoption is permitted. The amendments in this ASU may be applied either (1) prospectively to financial statements issued for reporting periods after the effective date of this ASU or (2) retrospectively to all prior periods presented in the financial statements. We are currently evaluating the impact this ASU will have on our disclosures.
v3.25.4
Acquisitions and Other Transactions
 12 Months Ended
Dec. 31, 2025
Business Combination, Asset Acquisition, Transaction between Entities under Common Control, and Joint Venture Formation [Abstract]  
Acquisitions and Other Transactions Acquisitions and Other Transactions
Northwind Midstream Acquisition
On August 29, 2025, MPLX completed the acquisition of 100 percent of the outstanding membership interests of Northwind Delaware Holdings LLC (“Northwind Midstream”) for $2.4 billion in cash (the “Northwind Midstream Acquisition”). Northwind Midstream provides sour gas gathering and treating services in Lea County, New Mexico, which enhances MPLX’s Permian natural gas and NGL value chain. The Northwind Midstream Acquisition was financed with a portion of the net proceeds from MPLX's $4.5 billion senior notes issued in August 2025.
Northwind Midstream consists of over 200,000 dedicated acres, more than 200 miles of gathering pipelines, two in-service acid gas injection wells at 20 MMcf/d and a third permitted well that will bring its total capacity to 37 MMcf/d. At the time of acquisition, the system had 150 MMcf/d of sour gas treating capacity, with in-process expansion projects expected to increase capacity to over 400 MMcf/d by the second half of 2026. The system is partially supported by minimum volume commitments by regional producers.
The Northwind Midstream Acquisition was accounted for as a business combination requiring all Northwind Midstream assets and liabilities to be remeasured to fair value. The fair value of property, plant and equipment was based primarily on the cost approach. The fair value of the identifiable intangible assets was primarily based on the multi-period excess earnings method, which is an income approach. The intangible assets acquired are related to various commercial contracts with a weighted average amortization period of 15 years.
The following table reflects our preliminary allocation of the $2.4 billion purchase price of the Northwind Midstream assets and liabilities, as well as measurement period adjustments since the acquisition date:
(In millions)August 29,
2025		AdjustmentsDecember 31,
2025
Assets acquired:
Cash and cash equivalents$17 $— $17 
Receivables11 — 11 
Other current assets1 — 1 
Property, plant and equipment1,182 (13)1,169 
Intangibles951 — 951 
Other noncurrent assets2 — 2 
Total assets acquired2,164 (13)2,151 
Liabilities assumed:
Accounts payable15 7 22 
Accrued property, plant and equipment84 — 84 
Accrued liabilities6 3 9 
Other current liabilities1 — 1 
Long-term operating lease liabilities1 — 1 
Total liabilities assumed107 10 117 
Total identifiable net assets2,057 (23)2,034 
Goodwill356 23 379 
Fair value of net assets acquired$2,413 $— $2,413 
The allocation is subject to revision, as certain data necessary to complete the purchase price allocation is not yet available, including, but not limited to, the final valuation of property, plant and equipment and intangible assets acquired, which may impact the amount of goodwill recognized. The final valuation will be completed no later than one year from the acquisition date. The results for the acquired business are reported within our Natural Gas and NGL Services segment.
The purchase price allocation resulted in the recognition of $379 million in goodwill by our Natural Gas and NGL Services segment, all of which is deductible for tax purposes. Goodwill represents the accelerated growth opportunities in the Permian using Northwind Midstream's asset base, which is complementary and adjacent to MPLX's existing Delaware basin natural gas system and offers optionality to direct volumes through our integrated system.
Pro forma financial information assuming the Northwind Midstream Acquisition had occurred as of the beginning of the calendar year prior to the year of the acquisition, as well as the revenues and earnings generated during the period since the acquisition date, were not material for disclosure purposes.
Divestiture of Rockies Operations
On November 12, 2025, MPLX completed the sale of its Rockies gathering and processing operations (the “Rockies”) to a subsidiary of Harvest Midstream (“Harvest”) for $980 million in cash. The transaction resulted in a gain of $159 million, which is included in Other income on the accompanying Consolidated Statements of Income. The sale of these non-core gathering and processing assets did not represent a strategic shift that has or will have a material effect on our operations or financial results. Prior to the sale, the Rockies operations were reported within the Natural Gas and NGL Services segment.
BANGL, LLC Acquisitions
BANGL, LLC (“BANGL”) owns and operates an NGL pipeline system that connects production in the Delaware and Midland basins to key demand centers along the Gulf Coast. On July 31, 2024, MPLX exercised its right of first offer under the BANGL joint venture agreement to purchase an additional 20 percent ownership interest in BANGL for $210 million in cash, which increased its total ownership interest to 45 percent (the “2024 BANGL Transaction”). The purchase price of the additional 20 percent ownership interest in BANGL exceeded our portion of the underlying net assets of the joint venture by approximately $156 million. Following the 2024 BANGL Transaction, our investment in BANGL continued to be accounted for as an equity method investment.
On July 1, 2025, MPLX purchased the remaining 55 percent interest in BANGL for $703 million in cash, plus an earnout provision of up to $275 million based on targeted EBITDA growth from 2026 to 2029 (the “BANGL Acquisition”). We recorded a liability for these contingent payments in the third quarter of 2025. See Note 15 for additional details on the inputs used to measure the fair value of these contingent payments. On July 3, 2025, MPLX used cash on hand to extinguish approximately $656 million principal amount of debt outstanding, including interest, related to certain term and revolving loans assumed as part of the BANGL Acquisition (the “BANGL Debt Repayment”).
Upon acquisition of the remaining 55 percent interest in BANGL, our existing equity investment was remeasured to fair value resulting in the recognition of a $484 million gain, which is included in Gain on equity method investments within the accompanying Consolidated Statements of Income. The fair value of the previously held equity method investment was estimated using an income approach, with significant valuation inputs including forecasted cash flows and discount rates ranging from 11 to 12 percent. As a result of the BANGL Acquisition, we now own 100 percent of BANGL and its results are reflected in our Natural Gas and NGL Services segment within our consolidated financial results.
The following table summarizes the purchase price consideration in connection with the BANGL Acquisition:
Total cash paid$703 
Fair value of contingent consideration as of acquisition date234 
Total consideration937 
Fair value of previously held equity interest766 
Fair value of net assets acquired$1,703 
The BANGL Acquisition was accounted for as a business combination requiring all BANGL assets and liabilities to be remeasured to fair value. The fair value of property, plant and equipment was determined using a combination of both the cost and income approach. The fair value of the identifiable intangible assets was primarily based on the multi-period excess earnings method, which is an income approach. The intangible asset acquired is related to a customer relationship with an amortization period of 11 years. The following table reflects our preliminary determination of the fair value of the BANGL assets and liabilities:
(In millions)July 1,
2025
Assets acquired:
Cash and cash equivalents$18 
Other current assets4 
Property, plant and equipment1,550 
Intangibles77 
Other noncurrent assets22 
Total assets acquired1,671 
Liabilities assumed:
Long-term debt due within one year46 
Other current liabilities42 
Long-term debt610 
Other long-term liabilities1 
Total liabilities assumed699 
Total identifiable net assets972 
Goodwill731 
Fair value of net assets acquired$1,703 
The allocation is subject to revision, as certain data necessary to complete the purchase price allocation is not yet available, including, but not limited to, the final valuation of property, plant and equipment and intangible assets acquired, which may impact the amount of goodwill recognized. The final valuation will be completed no later than one year from the acquisition date.
The purchase price allocation resulted in the recognition of $731 million in goodwill by our Natural Gas and NGL Services segment, 55 percent of which is deductible for tax purposes. Goodwill represents the advancement of our wellhead-to-water strategy by securing full ownership of a strategically located NGL transport asset which further integrates our midstream infrastructure connecting the Permian and Gulf Coast regions.
Pro forma financial information assuming the BANGL Acquisition had occurred as of the beginning of the calendar year prior to the year of the acquisition, as well as the revenues and earnings generated during the period since the acquisition date, were not material for disclosure purposes.
Matterhorn Express Pipeline Acquisition
On June 16, 2025, MPLX purchased an additional 5 percent ownership interest in the joint venture that owns and operates the Matterhorn Express pipeline for $151 million, bringing our total interest to 10 percent. The pipeline is designed to transport natural gas from the Permian basin to the Katy area near Houston. The purchase price of the additional 5 percent ownership interest in the joint venture exceeded the amount of the claim to the underlying net assets of the joint venture by approximately $124 million, with $63 million of this difference attributed to property, plant and equipment and $61 million attributed to customer-related intangibles. The amounts attributed to property, plant and equipment and customer-related intangibles will be amortized to net income over the remaining useful lives of the assets and the weighted average remaining term of the customer contracts,
respectively. Our investment in the joint venture that owns and operates the Matterhorn Express pipeline continues to be accounted for as an equity method investment within our Natural Gas and NGL Services segment.
Whiptail Midstream Acquisition
On March 11, 2025, MPLX acquired gathering businesses from Whiptail Midstream, LLC for $235 million in cash. These San Juan basin assets consist primarily of crude and natural gas gathering systems in the Four Corners region, and enhance our strategic relationship with MPC. The acquisition was accounted for as a business combination, which requires all the identifiable assets acquired and liabilities assumed to be remeasured to fair value at the date of acquisition. The final valuation includes $170 million of property, plant and equipment, $41 million of intangibles and $24 million of net working capital. The results for the acquired business are allocated between our two segments based on the product-based value chain the underlying assets support.
Whistler Joint Venture Transaction
On May 29, 2024, MPLX and its joint venture partner contributed their respective membership interests in Whistler Pipeline, LLC to a newly formed joint venture, WPC Parent, LLC, and issued a 19 percent voting interest in WPC Parent, LLC to an affiliate of Enbridge Inc. in exchange for the contribution of cash and the Rio Bravo Pipeline project (collectively, the “Whistler Joint Venture Transaction”). As a result of the transaction, MPLX’s voting interest in the joint venture was reduced from 37.5 percent to 30.4 percent. MPLX recognized a gain of $151 million and received a cash distribution of $134 million, recorded as a return of capital, related to the dilution of the ownership interest. The gain is included in Income from equity method investments on the accompanying Consolidated Statements of Income and the return of capital is included in Investments - redemptions, repayments, return of capital and sales proceeds within the investing section of the accompanying Consolidated Statements of Cash Flows.
Utica Midstream Acquisition
On March 22, 2024, MPLX used $625 million of cash to purchase additional ownership interests in existing joint ventures and gathering assets (the “Utica Midstream Acquisition”), which will enhance our position in the Utica basin. Prior to the acquisition, we owned an indirect interest in Ohio Gathering Company L.L.C. (“OGC”) and a direct interest in Ohio Condensate Company L.L.C. (“OCC”). After giving effect to the acquisition, MPLX owns a combined direct and indirect 73 percent interest in OGC and a 100 percent interest in OCC. In addition, MPLX acquired a 100 percent interest in a dry gas gathering system in the Utica basin, including 53 miles of gathering pipeline and three dehydration units with a combined capacity of approximately 620 MMcf/d. OGC continues to be accounted for as an equity method investment, as MPLX did not obtain control of OGC as a result of the transaction. The acquisition date fair value of our investment in OGC exceeded our portion of the underlying net assets of the joint venture by approximately $75 million. This basis difference is being amortized into net income over the remaining estimated useful lives of the underlying net assets. OCC was previously accounted for as an equity method investment, and it is now reflected as a consolidated subsidiary within our consolidated financial results. The results for the acquired business are reported within our Natural Gas and NGL Services segment.
The Utica Midstream Acquisition was accounted for as a business combination requiring all the acquired assets and liabilities to be remeasured to fair value resulting in a consolidated fair value of net assets and liabilities of $625 million. The fair value includes $507 million related to acquired interests in the joint ventures and the remaining balance related to other acquired assets and liabilities. The revaluation of MPLX’s existing 62 percent equity method investment in OCC resulted in a $20 million gain, which is included in Gain on equity method investments within the accompanying Consolidated Statements of Income. The fair value of equity method investments was based on a discounted cash flow model.
Acquisition of 40 Percent Interest in MarkWest Torñado GP, L.L.C.
On December 15, 2023, MPLX used $303 million of cash on hand to purchase the remaining 40 percent interest in MarkWest Torñado GP, L.L.C. (“Torñado”) for approximately $270 million, including cash paid for working capital, and to extend the term of a gathering and processing agreement for approximately $33 million. As a result of this transaction, we now own 100 percent of Torñado and reflect it as a consolidated subsidiary within our consolidated financial results. It was previously accounted for as an equity method investment. Torñado provides natural gas gathering and processing related services in the Permian basin. Its assets include two gas processing plants, each with a capacity of 200 MMcf/d and approximately 142 miles of gathering pipeline. The results for this business are reported under our Natural Gas and NGL Services segment.
At December 15, 2023, the carrying value of our 60 percent equity investment in Torñado was $311 million. Upon acquisition of the remaining 40 percent member interest, our existing equity investment was remeasured to fair value resulting in the recognition of a $92 million gain, which is included in Gain on equity method investments within the accompanying Consolidated Statements of Income. The fair value of the previously-held equity method investment was primarily based on the price negotiated for the 40 percent interest in Torñado.
The acquisition was accounted for as a business combination requiring all of the Torñado assets and liabilities to be remeasured to fair value resulting in a consolidated fair value of net assets and liabilities of $673 million. The fair value of property, plant and equipment was based primarily on the cost approach. The fair value of the identifiable intangible assets, consisting of various
customer contracts, was primarily based on the multi-period excess earnings method, which is an income approach. The following table reflects our determination of the fair value of the Torñado assets and liabilities (in millions):
(In millions)
Property, Plant and Equipment$585 
Intangibles75 
Working capital, net 30 
Other Long-term assets and liabilities, net(17)
Total net assets and liabilities$673 
Pro forma financial information assuming the acquisition had occurred as of the beginning of the calendar year prior to the year of the acquisition, as well as the revenues and earnings generated during the period since the acquisition date, were not material for disclosure purposes.
v3.25.4
Investments and Noncontrolling Interests
 12 Months Ended
Dec. 31, 2025
Equity Method Investments and Joint Ventures [Abstract]  
Investments and Noncontrolling Interests quity Method Investments
The following table presents MPLX’s equity method investments at the dates indicated:
Ownership as ofCarrying value at
December 31,December 31,
(In millions, except ownership percentages)VIE202520252024
Crude Oil and Products Logistics
Illinois Extension Pipeline Company, L.L.C.35%$208 $218 
LOOP LLC41%313 310 
MarEn Bakken Company LLC(1)
25%502 526 
Other(2)
X558 541 
Total Crude Oil and Products Logistics
1,581 1,595 
Natural Gas and NGL Services
BANGL, LLC(3)
— 281 
MarkWest EMG Jefferson Dry Gas Gathering Company, L.L.C.(4)
X67%407 329 
MarkWest Utica EMG, L.L.C.X61%890 742 
Ohio Gathering Company L.L.C.(5)
X32%444 470 
Sherwood Midstream LLCX50%475 488 
Texas City Logistics LLCX50%163 — 
WPC Parent, LLC30%273 208 
Other(2)
X565 418 
Total Natural Gas and NGL Services
3,217 2,936 
Total$4,798 $4,531 
(1)    The investment in MarEn Bakken Company LLC includes our 9.19 percent indirect interest in a joint venture (“Dakota Access”) that owns and operates the Dakota Access Pipeline and Energy Transfer Crude Oil Pipeline projects (collectively, the “Bakken Pipeline system”).
(2)    Included within Other are certain equity method investments that have been deemed to be VIEs. The December 31, 2024 Natural Gas and NGL Services value includes $129 million in investments associated with the Rockies, which were divested in the fourth quarter 2025.
(3)    At December 31, 2024, we owned a 45 percent interest in BANGL. On July 1, 2025, we acquired the remaining 55 percent interest in BANGL. As a result of acquiring the remaining interest, we obtained control and now consolidate BANGL.
(4)    On March 31, 2025, MPLX contributed a wholly-owned subsidiary with a fair value of $125 million to MarkWest EMG Jefferson Dry Gas Gathering Company, L.L.C. As a result of the transaction, MPLX received special distributions of $42 million in 2025, which are reflected as a return of capital on the Consolidated Statement of Cash Flows.
(5)    MPLX also holds a 41 percent indirect interest in OGC through our ownership interest in MarkWest Utica EMG, L.L.C.
For those entities that have been deemed to be VIEs, neither MPLX nor any of its subsidiaries have been deemed to be the primary beneficiary due to voting rights on significant matters. While we have the ability to exercise influence through participation in the management committees which make all significant decisions, we have equal influence over each committee as a joint interest partner and all significant decisions require the consent of the other investors without regard to economic interest. As such, we have determined that these entities should not be consolidated and applied the equity method of accounting with respect to our investments in each entity.
MPLX’s maximum exposure to loss as a result of its involvement with equity method investments generally includes its equity investment, any additional capital contribution commitments and any operating expenses incurred by the subsidiary operator in excess of its compensation received for the performance of the operating services. MPLX did not provide any financial support to equity method investments that it was not contractually obligated to provide during the years ended December 31, 2025, 2024 and 2023. See Note 22 for information on our guarantees related to equity method investees.
From time to time, changes in the design or nature of the activities of our equity method investments may require us to reconsider our conclusions on the entity’s status as a VIE and/or our status as the primary beneficiary. Such reconsideration could result in a change in the classification of the equity method investment.
Summarized financial information for MPLX’s equity method investments is as follows:
(In millions)202520242023
Income statement data:
Revenues and other income$3,959 $3,594 $3,262 
Costs and expenses1,579 1,535 1,331 
Income from operations2,380 2,059 1,930 
Net income1,854 1,631 1,634 
Balance sheet data:
Current assets1,347 1,570 1,531 
Noncurrent assets 20,199 17,927 13,860 
Current liabilities1,044 746 979 
Noncurrent liabilities 7,011 6,711 4,856 
As of December 31, 2025 and 2024, the carrying value of MPLX’s equity method investments in the Crude Oil and Products Logistics segment exceeded the underlying net assets of its investees by $283 million and $291 million, respectively. As of December 31, 2025 and 2024, the carrying value of MPLX’s equity method investments in the Natural Gas and NGL Services segment exceeded the underlying net assets of its equity method investments by approximately $124 million and $198 million, respectively.
At both December 31, 2025 and 2024, the Crude Oil and Products Logistics basis difference related to goodwill was $167 million. At December 31, 2025 and 2024, the Natural Gas and NGL Services basis difference related to goodwill was $0 million and $31 million, respectively, with the remaining basis differences primarily attributable to property, plant and equipment and intangible assets that will be amortized over the assets’ remaining useful life.
v3.25.4
Related Party Agreements and Transactions
 12 Months Ended
Dec. 31, 2025
Related Party Transactions [Abstract]  
Related Party Transactions Disclosure [Text Block] Related Party Agreements and Transactions
MPLX engages in transactions with both MPC and certain of its equity method investments as part of its normal business; however, transactions with MPC make up the majority of MPLX’s related party transactions. Transactions with related parties are further described below.
Commercial Agreements
MPLX has various long-term, fee-based commercial agreements with MPC. Under these agreements, MPLX provides transportation, gathering, terminal, fuels distribution, marketing, storage, management, operational and other services to MPC. MPC has committed to provide MPLX with minimum quarterly throughput volumes on crude oil and refined products and other fees for storage capacity; operating and management fees; and reimbursements for certain direct and indirect costs. MPC has also committed to provide a fixed fee for 100 percent of available capacity for boats, barges and third-party chartered equipment under the marine transportation service agreements.
The commercial agreements with MPC include:
•MPLX has a fuels distribution agreement with MPC under which MPC pays MPLX a tiered monthly volume-based fee for marketing and selling MPC’s products. This agreement is subject to a minimum quarterly volume and has an initial term of 10 years, subject to a five-year renewal period under terms to be renegotiated at that time.
•MPLX has various pipeline transportation agreements under which MPC pays MPLX fees for transporting crude and refined products on MPLX’s pipeline systems. These agreements are subject to minimum throughput volumes under which MPC will pay MPLX deficiency payments for any period in which they do not ship the minimum committed volume. Under certain agreements, deficiency payments can be applied as credits to future periods in which MPC ships volumes in excess of the minimum volume, subject to a limited period of time. These agreements are subject to various terms and renewal periods.
•MPLX has a marine transportation agreement with an initial term of three years under which MPC pays MPLX fees for providing marine transportation of crude oil, feedstock and refined petroleum products, and related services. This agreement is subject to two renewal periods of three years each.
•MPLX has numerous storage services agreements governing storage services at various types of facilities including terminals, pipeline tank farms, caverns and refineries, under which MPC pays MPLX per-barrel fees for providing storage services. Some of these agreements provide MPC with exclusive access to storage at certain locations, such as storage located at MPC’s refineries or storage in certain caverns. Under these agreements, MPC pays MPLX a per-barrel fee for such storage capacity, regardless of whether MPC fully utilizes the available capacity. These agreements are subject to various terms and renewal periods.
•MPLX has multiple terminal services agreements governing certain terminals under which MPC pays MPLX fees for terminal services. Under these agreements MPC pays MPLX agreed upon fees relating to MPC product receipts, deliveries and storage as well as any blending, additization, handling, transfers or other related charges. Many of these agreements are subject to minimum volume throughput commitments, or to various minimum commitments related to some or all terminal activities, under which MPC pays a deficiency payment for any period in which they do not meet the minimum commitment. Some of these agreements allow for deficiency payments to be applied as credits to a limited number of future periods with excess throughput volumes. These agreements are subject to various terms and renewal periods.
•MPLX had a keep-whole commodity agreement with MPC under which MPC paid us a processing fee for NGLs related to keep-whole agreements and we paid MPC a marketing fee in exchange for assuming the commodity risk. The pricing structure under this agreement provided for a base volume subject to a base rate and incremental volumes subject to variable rates, which were calculated with reference to certain of our costs incurred as processor of the volumes. The pricing for both the base and incremental volumes were subject to revision each year. This agreement expired in March 2025.
•MPLX has an agreement with MPC under which it provides management services to assist MPC in the oversight and management of the marine business. MPLX receives fixed annual fees for providing the required services, which are subject to predetermined annual escalation rates. This agreement is subject to an initial term of five years and automatically renews for one additional five-year renewal period unless terminated by either party.
In many cases, agreements are location-based hybrid agreements, containing provisions relating to multiple of the types of agreements and services described above.
Operating Agreements
MPLX operates various pipelines owned by MPC under operating services agreements. Under these operating services agreements, MPLX receives a fee for operating the assets and is reimbursed for all associated direct and indirect costs. Most of these agreements are indexed for inflation. These agreements range from one to ten years in length and automatically renew unless terminated by either party.
MPLX also receives management fee revenue for engineering, construction and administrative services for operating certain of its equity method investments. Amounts earned under these management agreements are classified as Other income-related parties in the Consolidated Statements of Income.
Co-location Services Agreements
MPLX is party to co-location services agreements with MPC’s refineries under which MPC provides management, operational and other services to MPLX. MPLX pays MPC monthly fixed fees and direct reimbursements for such services calculated as set forth in the agreements. These agreements have initial terms of 50 years.
Ground Lease Agreements
MPLX is party to ground lease agreements with certain of MPC’s refineries under which MPLX is the lessee of certain sections of property which contain facilities owned by MPLX and are within the premises of MPC’s refineries. MPLX pays MPC monthly fixed fees under these ground leases. These agreements are subject to various terms.
Omnibus Agreements
MPLX has omnibus agreements with MPC that address MPLX’s payment of fixed annual fees to MPC for the provision of executive management services by certain executive officers of the general partner and MPLX’s reimbursement of MPC for the provision of certain general and administrative services to it (“Omnibus Charges”). They also provide for MPC’s indemnification to MPLX for certain matters, including environmental, title and tax matters, as well as our indemnification of MPC for certain matters under these agreements.
The omnibus agreements also provide for other reimbursements, including certain capital and expense projects. Capital project reimbursements are recognized as contributions from MPC. Expense project reimbursements are recognized as either revenue over the remaining term of the applicable agreement or as an offset to expense.
Employee Services Agreements
MPLX has various employee services agreements and secondment agreements with MPC under which MPLX reimburses MPC for employee benefit expenses, along with the provision of operational and management services in support of both our Crude Oil and Products Logistics and Natural Gas and NGL Services segments’ operations (“ESA Charges”).
Related Party Loan
MPLX is party to a loan agreement with MPC (the “MPC Loan Agreement”). Under the terms of the MPC Loan Agreement, MPC extends loans to MPLX on a revolving basis as requested by MPLX and as agreed to by MPC. The borrowing capacity of the MPC Loan Agreement is $1.5 billion aggregate principal amount of all loans outstanding at any one time. The MPC Loan Agreement is scheduled to expire, and borrowings under the loan agreement are scheduled to mature and become due and
payable, on July 31, 2029, provided that MPC may demand payment of all or any portion of the outstanding principal amount of the loan, together with all accrued and unpaid interest and other amounts (if any), at any time prior to maturity. Borrowings under the MPC Loan Agreement bear interest at one-month term SOFR adjusted upward by 0.10 percent plus 1.25 percent or such lower rate as would be applicable to such loans under the MPLX Credit Agreement as discussed in Note 17.
Activity on the MPC Loan Agreement for the year ended December 31, 2025 is summarized in the table below. There was no activity on the MPC Loan Agreement for the years ended December 31, 2024 and 2023.
(In millions, except %)2025
Borrowings$50 
Weighted average interest rate of borrowings5.68 %
Repayments$50 
Outstanding balance at end of period$— 
Related Party Revenue and Other Income
Related party revenue consists primarily of revenue recognized from commercial agreements with MPC as well as fees charged under operating agreements with MPC and our equity affiliates as discussed above.
Certain product sales to MPC and other related parties net to zero within the consolidated financial statements as the transactions are recorded net due to the terms of the agreements under which such product was sold. For the years ended December 31, 2025, 2024 and 2023, these sales totaled $627 million, $754 million and $739 million, respectively.
Related Party Expenses
Related party expenses consist primarily of Omnibus Charges, ESA Charges, and fees paid under the co-location agreements and ground lease agreements as outlined above. Omnibus Charges and ESA Charges are classified as Rental cost of sales - related parties, Purchases - related parties, or General and administrative expenses depending on the nature of the asset or activity with which the costs are associated. Additionally, we incur costs under agreements for transportation and processing services with certain of our unconsolidated affiliates.
In addition to these agreements, MPLX purchases products from MPC, makes payments to MPC in its capacity as general contractor to MPLX, and has certain rent and lease agreements with MPC.
For the years ended December 31, 2025, 2024 and 2023, General and administrative expenses incurred from MPC totaled $299 million, $289 million and $262 million, respectively.
Some charges incurred under the omnibus and employee service agreements are related to engineering services and are associated with assets under construction. These charges are added to Property, plant and equipment, net on the Consolidated Balance Sheets. For 2025, 2024 and 2023, these charges totaled $230 million, $182 million and $94 million, respectively.
Related Party Assets and Liabilities
Assets and liabilities with related parties appearing in the Consolidated Balance Sheets are detailed in the table below. This table identifies the various components of related party assets and liabilities, including those associated with leases (see Note 21 for additional information) and deferred revenue.
December 31,
(In millions)20252024
Current assets - related parties
Receivables$624 $620 
Lease receivables269 204 
Prepaid5 5 
Other1 1 
Total899 830 
Noncurrent assets - related parties
Long-term lease receivables421 677 
Right of use assets239 226 
Unguaranteed residual asset263 189 
Long-term receivables39 28 
Total962 1,120 
Current liabilities - related parties
MPC loan agreement and other payables(1)
290 288 
Deferred revenue107 106 
Operating lease liabilities2 2 
Total399 396 
Long-term liabilities - related parties
Long-term operating lease liabilities237 224 
Long-term deferred revenue127 110 
Total$364 $334 
(1)    There were no borrowings outstanding on the MPC Loan Agreement as of December 31, 2025 or December 31, 2024.
Other Related Party Transactions
From time to time, MPLX may also sell to or purchase from related parties, assets and inventory at the lesser of average unit cost or net realizable value.
v3.25.4
Equity
 12 Months Ended
Dec. 31, 2025
Equity [Abstract]  
Equity Equity
Units Outstanding
MPLX had 1,015,702,040 common units outstanding as of December 31, 2025. Of that number, 647,415,452 were owned by MPC. The changes in the number of common units during the years ended December 31, 2023, 2024 and 2025 are summarized below:
(In units)Common Units
Balance at December 31, 20221,001,020,616 
Unit-based compensation awards196,428 
Conversion of Series A preferred units2,281,831 
Balance at December 31, 20231,003,498,875 
Unit-based compensation awards141,985 
Conversion of Series A preferred units(1)
21,078,998 
Units redeemed in unit repurchase program(7,577,568)
Balance at December 31, 20241,017,142,290 
Unit-based compensation awards147,670 
Conversion of Series A preferred units(1)
6,166,965 
Units redeemed in unit repurchase program(7,754,885)
Balance at December 31, 20251,015,702,040 
(1)    Certain Series A preferred unitholders have exercised their rights to convert their Series A preferred units into common units as discussed in Note 9.
Unit Repurchase Program
On August 5, 2025, we announced a board authorization for the repurchase of $1.0 billion of MPLX common units held by the public in addition to the $1.0 billion common unit repurchase authorization announced on August 2, 2022. These unit repurchase authorizations have no expiration date. We may utilize various methods to effect the repurchases, which could include open market repurchases, negotiated block transactions, accelerated unit repurchases, tender offers or open market solicitations for units, some of which may be effected through Rule 10b5-1 plans. The timing and amount of future repurchases, if any, will depend upon several factors, including market and business conditions, and such repurchases may be suspended, discontinued or restarted at any time.
Total unit repurchases were as follows for the years ended December 31, 2025, 2024 and 2023:
(In millions, except per unit data)202520242023
Number of common units repurchased8 8 — 
Cash paid for common units repurchased(1)
$400 $326 $— 
Average cost per unit(1)
$51.58 $43.04 $— 
(1)Cash paid for common units repurchased and average cost per unit includes commissions paid to brokers during the period.
As of December 31, 2025, we had $1,120 million remaining under the unit repurchase authorizations.
Redemption of the Series B Preferred Units
On February 15, 2023, MPLX exercised its right to redeem all 600,000 units of 6.875 percent Fixed-to-Floating Rate Cumulative Redeemable Perpetual Preferred Units (the “Series B preferred units”). MPLX paid unitholders the Series B preferred unit redemption price of $1,000 per unit. MPLX made a final cash distribution of $21 million to Series B preferred unitholders on February 15, 2023, in conjunction with the redemption.
The changes in the Series B preferred unit balance during 2023 are included in the Consolidated Statements of Equity within Series B preferred units.
Cash Distributions
Total distributions declared for the years ended December 31, 2025, 2024 and 2023 are summarized in the table below.
202520242023
Distributions per common unit$4.066 $3.613 $3.250 
The allocation of total quarterly cash distributions to common and preferred unitholders is as follows for the years ended December 31, 2025, 2024 and 2023. The Sixth Amended and Restated Agreement of Limited Partnership, dated as of February 1, 2021 (“Partnership Agreement”) sets forth the calculation to be used to determine the amount and priority of cash distributions that the common unitholders and preferred unitholders will receive. MPLX’s distributions are declared for the prior quarter subsequent to the quarter end; therefore, the following table represents total cash distributions applicable to the period for which the distributions relate as opposed to the quarter in which they were declared and paid.
(In millions)202520242023
Common and preferred unit distributions:
Common unitholders, includes common units of general partner$4,138 $3,678 $3,256 
Series A preferred unit distributions— 27 94 
Series B preferred unit distributions(1)
— — 5 
Total cash distributions declared$4,138 $3,705 $3,355 
(1)    2023 period includes the portion of the $21 million distribution paid to the Series B preferred unitholders on February 15, 2023 that was earned during the period prior to the redemption.
On January 29, 2026, MPLX declared a quarterly cash distribution, based on the results of the fourth quarter of 2025, totaling $1,092 million, or $1.0765 per common unit. This distribution was paid on February 17, 2026 to unitholders of record on February 9, 2026.
v3.25.4
Net Income Per Limited Partner Unit
 12 Months Ended
Dec. 31, 2025
Earnings Per Share [Abstract]  
Net Income Per Limited Partner Unit [Text Block] Net Income Per Limited Partner Unit
Net income per unit applicable to common limited partner units is computed by dividing net income attributable to MPLX LP less income allocated to participating securities by the weighted average number of common units outstanding.
During the years ended December 31, 2025, 2024 and 2023, MPLX had participating securities consisting of common units, certain equity-based compensation awards, Series A preferred units, and Series B preferred units as well as dilutive potential common units related to certain equity-based compensation awards. Potential common units that were anti-dilutive, and therefore omitted from the diluted earnings per unit calculation for the years ended December 31, 2025, 2024 and 2023, were less than 1 million.
(In millions, except per unit data)202520242023
Net income attributable to MPLX LP(1):
$4,912 $4,317 $3,928 
Less: Distributions declared on Series A preferred units— 27 94 
Distributions declared on Series B preferred units— — 5 
Distributed and undistributed earnings allocated to other participating securities
3 9 16 
Impact of redemption of Series B preferred units— — 5 
Net Income available to common unitholders$4,909 $4,281 $3,808 
Weighted average units outstanding:
Basic1,019 1,016 1,001 
Diluted1,019 1,017 1,002 
Net income attributable to MPLX LP per limited partner unit:
Basic$4.82 $4.21 $3.80 
Diluted$4.82 $4.21 $3.80 
(1)    Allocation of net income attributable to MPLX LP assumes all earnings for the period have been distributed based on the distribution priorities applicable to the period.
v3.25.4
Redeemable Preferred Units
 12 Months Ended
Dec. 31, 2025
Redeemable Preferred Units Disclosure [Abstract]  
Preferred Stock Series A Preferred Units
Private Placement of Preferred Units
On May 13, 2016, MPLX completed the private placement of approximately 30.8 million 6.5 percent Series A Convertible preferred units for a cash purchase price of $32.50 per unit. The aggregate net proceeds of approximately $984 million from the sale of the Series A preferred units were used for capital expenditures, repayment of debt and general business purposes.
Preferred Unit Conversions
The following conversions were executed in accordance with the conversion provisions outlined in our Partnership Agreement. During the years ended December 31, 2024 and 2023, certain Series A preferred unitholders exercised their rights to convert their Series A preferred units into 21 million common units and 2 million common units, respectively. On February 11, 2025,
MPLX exercised its right to convert the remaining 6 million outstanding Series A preferred units into common units. As a result, there were no Series A preferred units outstanding at December 31, 2025.
For a summary of changes in the redeemable preferred balance for the years ended December 31, 2025, 2024 and 2023, see the Consolidated Statements of Equity.
Preferred Unit Distribution Rights

Prior to conversion, the Series A preferred units ranked senior to all common units and pari passu with all Series B preferred units with respect to distributions and rights upon liquidation. The holders of the Series A preferred units were entitled to receive, when and if declared by the board, a quarterly distribution equal to the greater of $0.528125 per unit or the amount of distributions they would have received on an as converted basis, including any supplemental distributions made to common unitholders.
Financial Statement Presentation
Prior to conversion, the Series A preferred units were considered redeemable securities under GAAP due to the existence of redemption provisions upon a deemed liquidation event, which is outside MPLX’s control. Therefore, they are presented as temporary equity in the mezzanine section of the Consolidated Balance Sheets for the year end December 31, 2024. The Series A preferred units were recorded at their issuance date fair value, net of issuance costs. Income allocations increased the carrying value and declared distributions decreased the carrying value of the Series A preferred units.
v3.25.4
Segment Information
 12 Months Ended
Dec. 31, 2025
Segment Reporting [Abstract]  
Segment Information
MPLX’s chief operating decision maker (“CODM”) is the chief executive officer of its general partner. The CODM reviews MPLX’s discrete financial information, makes operating decisions, assesses financial performance and allocates resources on a product-based value chain basis. MPLX has two reportable segments: Crude Oil and Products Logistics and Natural Gas and NGL Services. Each of these segments is organized and managed based upon the product-based value chain each supports.
•Crude Oil and Products Logistics – gathers, transports, stores and distributes crude oil, refined products, other hydrocarbon-based products and renewables. Also includes the operation of refining logistics, fuels distribution and inland marine businesses, terminals, rail facilities and storage caverns.
•Natural Gas and NGL Services – gathers, treats, processes and transports natural gas; and transports, fractionates, stores and markets NGLs.
The CODM evaluates the performance of our segments using Segment Adjusted EBITDA. The CODM uses Segment Adjusted EBITDA results and considers forecast-to-actual variances on a periodic basis when making decisions about allocating capital and personnel as a part of the annual business plan process and ongoing monitoring of performance. Amounts included in net income and excluded from Segment Adjusted EBITDA include: (i) depreciation and amortization; (ii) net interest and other financial costs; (iii) income/(loss) from equity method investments; (iv) distributions and adjustments related to equity method investments; (v) impairment expense; (vi) noncontrolling interests, (vii) transaction-related costs; and (viii) other adjustments as applicable. These items are either: (i) believed to be non-recurring in nature; (ii) not believed to be allocable or controlled by the segment; or (iii) are not tied to the operational performance of the segment. Assets by segment are not a measure used to assess the performance of the Partnership by our CODM and thus are not reported in our disclosures.
The tables below present information about our reportable segments:
(In millions)202520242023
Crude Oil and Products Logistics
Service revenue$4,824 $4,543 $4,335 
Rental income923 882 857 
Product related revenue16 18 18 
Sales-type lease revenue448 475 500 
Income from equity method investments243 269 270 
Other income121 152 68 
Total segment revenues and other income(1)
6,575 6,339 6,048 
Operating expenses2,173 2,097 2,006 
Other segment items(2)
(145)(133)(92)
Segment Adjusted EBITDA(3)
4,547 4,375 4,134 
Capital expenditures538 482 414 
Investments in unconsolidated affiliates(4)
— 93 8 
Natural Gas and NGL Services
Service revenue2,468 2,407 2,189 
Rental income226 222 208 
Product related revenue2,418 2,221 2,191 
Sales-type lease revenue151 136 136 
Income from equity method investments(5)
454 533 330 
Gain on equity method investments(6)
484 20 92 
Other income222 55 87 
Total segment revenues and other income(1)
6,423 5,594 5,233 
Purchased product costs1,815 1,561 1,598 
Operating expenses1,716 1,704 1,564 
Other segment items(2)
422 (60)(64)
Segment Adjusted EBITDA(3)
2,470 2,389 2,135 
Capital expenditures1,418 568 605 
Investments in unconsolidated affiliates(4)
$794 $143 $90 
(1)    Within the total segment revenues and other income amounts presented above, third-party revenues for the Crude Oil and Products Logistics segment were $751 million, $746 million and $701 million for the years ended December 31, 2025, 2024 and 2023, respectively. Third-party revenues for the Natural Gas and NGL Services segment were $6,210 million, $5,297 million and $4,902 million for the years ended December 31, 2025, 2024 and 2023, respectively.
(2)    Other segment items in the Crude Oil and Products Logistics segment include income from equity method investments, distributions and adjustments related to equity method investments, equity-based compensation and other miscellaneous items. Other segment items in the Natural Gas and NGL Services segment include income from and gain on equity method investments, distributions and adjustments related to equity method investments, gain on sale of assets, transaction-related costs, unrealized derivative gain/loss and other miscellaneous items.
(3)    See below for the reconciliation from Segment Adjusted EBITDA to Net income.
(4)    Investments in unconsolidated affiliates in the Crude Oil and Products Logistics segment includes a contribution of $92 million in 2024 to Dakota Access to fund our share of a debt repayment by the joint venture and excludes $18 million in 2024 related to acquisition of an additional interest in Wink to Webster Pipeline LLC. Investments in unconsolidated affiliates in the Natural Gas and NGL Services segment includes cash contributions to several joint ventures to fund current growth capital projects in 2025 and excludes $151 million in 2025 related to acquisition of an additional interest in the joint venture that owns and operates the Matterhorn Express Pipeline, a $49 million capital contribution in 2025 to WPC Parent, LLC to purchase Enbridge’s special membership interest in the Rio Bravo Pipeline project, a $13 million payment in 2025 related to earnout associated with MXP Parent, LLC, and $210 million in 2024 related to the acquisition of additional interests in BANGL, LLC.
(5)    Includes a $151 million gain related to the dilution of ownership interest in connection with the Whistler Joint Venture Transaction in 2024.
(6)    Gain on equity method investments represents the gain on remeasurement of our existing equity method investment in BANGL in conjunction with the BANGL Acquisition in 2025, the gain on remeasurement of our existing equity method investment in OCC in conjunction with the Utica Midstream Acquisition in 2024, and the gain on remeasurement of our existing equity method investment in Torñado in conjunction with the purchase of the remaining joint venture interest in 2023.
The table below provides a reconciliation of Segment Adjusted EBITDA for reportable segments to Net income.
(In millions)202520242023
Reconciliation to Net income:
Crude Oil and Products Logistics Segment Adjusted EBITDA
$4,547 $4,375 $4,134 
Natural Gas and NGL Services Segment Adjusted EBITDA
2,470 2,389 2,135 
Total reportable segments7,017 6,764 6,269 
Depreciation and amortization(1)
(1,351)(1,283)(1,213)
Net interest and other financial costs(983)(921)(923)
Income from equity method investments697 802 600 
Distributions/adjustments related to equity method investments(962)(928)(774)
Gain on equity method investments484 — 92 
Gain on sale of assets159 — — 
Transaction-related costs(2)
(33)— — 
Adjusted EBITDA attributable to noncontrolling interests44 44 42 
Garyville incident response costs(3)
— — (16)
Other(4)
(120)(121)(111)
Net income$4,952 $4,357 $3,966 
(1)    Depreciation and amortization attributable to Crude Oil and Products Logistics was $546 million, $526 million and $530 million for the years ended December 31, 2025, 2024 and 2023, respectively. Depreciation and amortization attributable to Natural Gas and NGL Services was $805 million, $757 million and $683 million for the years ended December 31, 2025, 2024 and 2023, respectively.
(2)    Transaction-related costs include costs associated with the Northwind Midstream Acquisition, the BANGL Acquisition and the divestiture of the Rockies gathering and processing operations discussed in Note 4.
(3)    In August 2023, a naphtha release and resulting fire occurred at our Garyville Tank Farm resulting in the loss of four storage tanks with a combined shell capacity of 894 thousand barrels. We incurred $16 million of incident response costs, net of insurance recoveries, during the year ended December 31, 2023.
(4)    Includes unrealized derivative gain/(loss), equity-based compensation, provision for income taxes and other miscellaneous items.
v3.25.4
Major Customers and Concentration of Credit Risk
 12 Months Ended
Dec. 31, 2025
Risks and Uncertainties [Abstract]  
Major Customers and Concentration of Credit Risk Major Customers and Concentration of Credit Risk
The table below shows, by segment, the percentage of total revenues and other income with MPC, which is our most significant customer and our largest concentration of credit risk.
202520242023
Total revenues and other income(1)
Crude Oil and Products Logistics88 %88 %88 %
Natural Gas and NGL Services2 %4 %5 %
Total48 %49 %50 %
(1)    The percent calculations for the year ended December 31, 2025 exclude a $484 million gain on remeasurement of our existing equity method investment in BANGL in conjunction with the BANGL Acquisition and a $159 million gain on divestiture of the Rockies. The percent calculations for the year ended December 31, 2024 exclude a gain of $151 million related to the dilution of ownership interest in connection with the Whistler Joint Venture Transaction. The percent calculations for the year ended December 31, 2023 exclude a $92 million gain on remeasurement of our existing equity investment in Torñado. See Note 4 for additional information.
Revenue from the sale of products purchased after services are provided is reported as Product sales on the Consolidated Statements of Income and recognized on a gross basis, as MPLX takes control of the product and is the principal in the transaction. For the years ended December 31, 2025 and 2023, revenues with one customer, primarily related to these NGL transactions, accounted for approximately 10 percent of our total revenues and other income.
MPLX has a concentration of trade receivables due from customers in the same industry: MPC, integrated oil companies, natural gas exploration and production companies, independent refining companies and other pipeline companies. These concentrations of customers may impact MPLX’s overall exposure to credit risk as they may be similarly affected by changes in economic, regulatory and other factors. MPLX manages its exposure to credit risk through credit analysis, credit limit approvals and monitoring procedures; and for certain transactions, it may request letters of credit, prepayments or guarantees.
v3.25.4
Inventories
 12 Months Ended
Dec. 31, 2025
Inventory Disclosure [Abstract]  
Inventories Inventories
Inventories consist of the following:
December 31,
(In millions)20252024
NGLs$5 $5 
Line fill2 18 
Spare parts, materials and supplies165 157 
Total inventories$172 $180 
v3.25.4
Property, Plant, and Equipment
 12 Months Ended
Dec. 31, 2025
Property, Plant and Equipment [Abstract]  
Property, Plant and Equipment Disclosure Property, Plant and Equipment
Property, plant and equipment with associated accumulated depreciation is shown below:
 Estimated
Useful Lives		December 31,
(In millions)20252024
Crude Oil and Products Logistics
Pipelines
15 - 50 years
$6,908 $6,627 
Refining logistics
15 - 20 years
1,990 1,867 
Terminals
15 - 40 years
1,869 1,726 
Marine
15 - 20 years
1,188 1,149 
Land, building and other
5 - 50 years
1,627 1,619 
Construction-in-progress227 201 
Total Crude Oil and Products Logistics property, plant and equipment
13,809 13,189 
Natural Gas and NGL Services
Gathering and transportation
5 - 40 years
9,379 7,789 
Treating, processing and fractionation
10 - 40 years
6,896 6,611 
Land, building and other
5 - 40 years
437 541 
Construction-in-progress1,238 274 
Total Natural Gas and NGL Services property, plant and equipment
17,950 15,215 
Total property, plant and equipment31,759 28,404 
Less accumulated depreciation10,061 9,250 
Property, plant and equipment, net$21,698 $19,154 
We capitalize interest as part of the cost of major projects during the construction period. Capitalized interest totaled $42 million, $19 million and $15 million for the years ended December 31, 2025, 2024 and 2023, respectively.
v3.25.4
Goodwill and Intangibles
 12 Months Ended
Dec. 31, 2025
Goodwill and Intangible Assets Disclosure [Abstract]  
Goodwill and Intangibles Goodwill and Intangibles
Goodwill
MPLX annually evaluates goodwill for impairment as of November 30, as well as whenever events or changes in circumstances indicate it is more likely than not that the fair value of a reporting unit with goodwill is less than its carrying amount.
Our reporting units are one level below our operating segments and are determined based on the way in which segment management operates and reviews each operating segment. We have five reporting units, four of which have goodwill allocated to them. For the annual impairment assessment as of November 30, 2025, management performed only a qualitative assessment for the four reporting units as we determined it was more likely than not that the fair values of the reporting units exceeded their carrying values. Total goodwill at December 31, 2025 was $8,755 million, and no impairment was recorded as a result of our November 30, 2025 annual goodwill impairment analysis.
The changes in carrying amount of goodwill were as follows for the periods presented:
(In millions)
Crude Oil and Products Logistics
Natural Gas and NGL ServicesTotal
Balance as of December 31, 2023$7,645 $— $7,645 
Impairment losses— — — 
Balance as of December 31, 20247,645 — 7,645 
Acquisitions(1)
— 1,110 1,110 
Impairment losses— — — 
Balance as of December 31, 20257,645 1,110 8,755 
Gross goodwill as of December 31, 20257,645 4,251 11,896 
Accumulated impairment losses— (3,141)(3,141)
Balance as of December 31, 2025$7,645 $1,110 $8,755 
(1)    Acquisitions in 2025 are inclusive of the Northwind Midstream Acquisition and the BANGL Acquisition.
Intangible Assets
MPLX’s intangible assets are comprised of customer contracts and relationships. Gross intangible assets with accumulated amortization as of December 31, 2025 and 2024 is shown below:
December 31, 2025December 31, 2024
(In millions)Gross
Accumulated Amortization(1)
NetGross
Accumulated Amortization(1)
Net
Crude Oil and Products Logistics$308 $(260)$48 $283 $(224)$59 
Natural Gas and NGL Services2,175 (826)1,349 1,363 (904)459 
$2,483 $(1,086)$1,397 $1,646 $(1,128)$518 
(1)    Amortization expense attributable to the Crude Oil and Products Logistics segment for the years ended December 31, 2025 and 2024 was $36 million and $35 million, respectively. Amortization expense attributable to the Natural Gas and NGL Services segment for the years ended December 31, 2025 and 2024 was $105 million and $99 million, respectively.
Estimated future amortization expense related to the intangible assets at December 31, 2025 is as follows:
(In millions)
2026$164 
2027136 
2028125 
202991 
203091 
2031 and thereafter790 
Total$1,397 
v3.25.4
Fair Value Measurements
 12 Months Ended
Dec. 31, 2025
Fair Value Disclosures [Abstract]  
Fair Value Disclosures [Text Block] Fair Value Measurements
Fair Values – Recurring
The following table presents the impact on the Consolidated Balance Sheets of MPLX’s assets and liabilities measured at fair value on a recurring basis as of December 31, 2025 and 2024 by fair value hierarchy level.
December 31,
20252024
(In millions)Level 1Level 2Level 3Level 1Level 2Level 3
Liabilities:
Embedded derivatives in commodity contracts
Other current liabilities$— $— $6 $— $— $10 
Other long-term liabilities— — 35 — — 48 
Total embedded derivatives in commodity contracts— — 41 — — 58 
Contingent consideration / Other long-term liabilities— — 236 — — — 
Total carrying value in Consolidated Balance Sheets$— $— $277 $— $— $58 
Level 3 instruments include a liability for contingent consideration related to the BANGL Acquisition earnout provision and an embedded derivative liability for a natural gas purchase commitment embedded in a keep-whole processing agreement.
The fair value calculation for the contingent consideration liability was estimated using discounted cash flows based on a Monte Carlo simulation. Future earnout payments are tied to the achievement of EBITDA growth from 2026 to 2029, which includes the significant unobservable input of forecasted throughput volumes. The earnout payment will continue to be remeasured at fair value each quarter with changes in fair value recognized in earnings until either the EBITDA targets are met or the earnout period ends, with the total payout capped at $275 million.
The fair value calculation for the embedded derivative liability for the natural gas purchase commitment used significant unobservable inputs including: (1) NGL prices interpolated and extrapolated due to inactive markets ranging from $0.60 to $1.19 per gallon with a weighted average of $0.72 per gallon and (2) a 100 percent probability of renewal for the five-year renewal term of the gas purchase commitment and related keep-whole processing agreement. Increases or decreases in the fractionation spread result in an increase or decrease in the fair value of the embedded derivative liability, respectively.
Changes in Level 3 Fair Value Measurements
The following table is a reconciliation of the net beginning and ending balances recorded for net liabilities classified as Level 3 in the fair value hierarchy.
(In millions)20252024
Beginning balance$(58)$(61)
Contingent consideration(1)
(234)— 
Unrealized and realized gain/(loss) included in Net income(2)
5 (10)
Settlements10 13 
Ending balance(277)(58)
The amount of total gain/(loss) for the period included in earnings attributable to the change in unrealized gain/(loss) relating to liabilities still held at end of period$7 $(7)
(1)    Liability recorded in the third quarter of 2025 related to the BANGL Acquisition earnout provision.
(2)    Gain/(loss) on derivatives embedded in commodity contracts are recorded in Purchased product costs in the Consolidated Statements of Income.
Fair Values – Reported
We believe the carrying value of our other financial instruments, including cash and cash equivalents, receivables, receivables from related parties, lease receivables, lease receivables from related parties, accounts payable, and payables to related parties, approximate fair value. MPLX’s fair value assessment incorporates a variety of considerations, including the duration of the instruments, MPC’s investment-grade credit rating, historical incurrence of credit losses, and expected insignificance of future credit losses, which includes an evaluation of counterparty credit risk. The recorded value of the amounts outstanding under the bank revolving credit facility, if any, approximates fair value due to the variable interest rate that approximates current market rates. Derivative instruments are recorded at fair value, based on available market information (see Note 16).
The fair value of MPLX’s debt is estimated based on average bid prices obtained from broker quotes and is categorized in Level 3 of the fair value hierarchy. The following table summarizes the fair value and carrying value of our third-party debt, excluding finance leases and unamortized debt issuance costs:
December 31,
20252024
(In millions)Fair ValueCarrying ValueFair ValueCarrying Value
Outstanding debt(1)
$24,887 $25,821 $19,574 $21,068 
(1)    Any amounts outstanding under the MPC Loan Agreement are not included in the table above, as the carrying value approximates fair value. This balance, if any, is reflected in Current liabilities - related parties in the Consolidated Balance Sheets.
v3.25.4
Derivative Financial Instruments
 12 Months Ended
Dec. 31, 2025
Derivative Instruments and Hedging Activities Disclosure [Abstract]  
Derivative Financial Instruments Derivative Financial Instruments
Embedded Derivative - MPLX has a natural gas purchase commitment embedded in a keep-whole processing agreement with a producer customer in the Southern Appalachia region expiring in December 2027. The customer has the unilateral option to extend the agreement for one five-year term through December 2032. For accounting purposes, the natural gas purchase commitment and the term extending option have been aggregated into a single compound embedded derivative. The probability of the customer exercising its option is determined based on assumptions about the customer’s potential business strategy decision points that may exist at the time they would elect whether to renew the contract. The changes in fair value of this compound embedded derivative are based on the difference between the contractual and index pricing, the probability of the producer customer exercising its option to extend, and the estimated favorability of these contracts compared to current market conditions. The changes in fair value are recorded in earnings through Purchased product costs in the Consolidated Statements of Income. For further information regarding the fair value measurement of derivative instruments, see Note 15. See Note 2 for a discussion of derivatives MPLX may use and the reasons for them. At December 31, 2025 and 2024, the estimated fair value of this contract was a liability of $41 million and $58 million, respectively.
As of December 31, 2025 and 2024, there were no derivative assets or liabilities that were offset in the Consolidated Balance Sheets.
The impact of MPLX’s derivative contracts not designated as hedging instruments and the location of gains and losses recognized in the Consolidated Statements of Income is summarized below:
(In millions)202520242023
Product sales
Realized gain$— $1 $7 
Product sales derivative gain— 1 7 
Purchased product costs
Realized loss(10)(13)(11)
Unrealized gain17 3 — 
Purchased product cost derivative (loss)/gain7 (10)(11)
Total derivative (loss)/gain included in Net Income$7 $(9)$(4)
v3.25.4
Debt
 12 Months Ended
Dec. 31, 2025
Debt Disclosure [Abstract]  
Debt Debt
MPLX’s outstanding borrowings consist of the following:
 December 31,
(In millions)20252024
MPLX LP:
MPLX Credit Agreement$— $— 
4.000% senior notes due February 15, 2025
— 500 
4.875% senior notes due June 1, 2025
— 1,189 
1.750% senior notes due March 1, 2026
1,500 1,500 
4.125% senior notes due March 1, 2027
1,250 1,250 
4.250% senior notes due December 1, 2027
732 732 
4.000% senior notes due March 15, 2028
1,250 1,250 
4.800% senior notes due February 15, 2029
750 750 
2.650% senior notes due August 15, 2030
1,500 1,500 
4.800% senior notes due February 15, 2031
1,250 — 
4.950% senior notes due September 1, 2032
1,000 1,000 
5.000% senior notes due January 15, 2033
750 — 
5.000% senior notes due March 1, 2033
1,100 1,100 
5.500% senior notes due June 1, 2034
1,650 1,650 
5.400% senior notes due April 1, 2035
1,000 — 
5.400% senior notes due September 15, 2035
1,500 — 
4.500% senior notes due April 15, 2038
1,750 1,750 
5.200% senior notes due March 1, 2047
1,000 1,000 
5.200% senior notes due December 1, 2047
487 487 
4.700% senior notes due April 15, 2048
1,500 1,500 
5.500% senior notes due February 15, 2049
1,500 1,500 
4.950% senior notes due March 14, 2052
1,500 1,500 
5.650% senior notes due March 1, 2053
500 500 
5.950% senior notes due April 1, 2055
1,000 — 
6.200% senior notes due September 15, 2055
1,000 — 
4.900% senior notes due April 15, 2058
500 500 
Consolidated subsidiaries:
MarkWest - 4.875% senior notes, due 2025
— 11 
ANDX - 4.250% - 5.200% senior notes, due 2027-2047
31 31 
Finance lease obligations(1)
6 6 
Total26,006 21,206 
Unamortized debt issuance costs(174)(126)
Unamortized discount(179)(132)
Amounts due within one year(1,502)(1,693)
Total long-term debt due after one year$24,151 $19,255 
(1)    See Note 21 for lease information.
The following table shows five years of scheduled debt payments, including payments on finance lease obligations, as of December 31, 2025:
(In millions) 
2026$1,503 
20272,002 
20281,250 
2029750 
20301,500 
Credit Agreement
MPLX Credit Agreement
MPLX’s credit agreement (the “MPLX Credit Agreement”) matures in July 2027 and, among other things, provides for a $2.0 billion unsecured revolving credit facility and letter of credit issuing capacity under the facility of up to $150 million. Letter of credit issuing capacity is included in, not in addition to, the $2.0 billion borrowing capacity. Borrowings under the MPLX Credit Agreement bear interest, at MPLX’s election, at either the Adjusted Term SOFR or the Alternate Base Rate, both as defined in the MPLX Credit Agreement, plus an applicable margin.
The borrowing capacity under the MPLX Credit Agreement may be increased by up to an additional $1.0 billion, subject to certain conditions, including the consent of lenders whose commitments would increase. In addition, the maturity date may be extended, for up to two additional one year periods, subject to, among other conditions, the approval of lenders holding the majority of the commitments then outstanding, provided that the commitments of any non-consenting lenders will terminate on the then-effective maturity date. MPLX is charged various fees and expenses in connection with the agreement, including administrative agent fees, commitment fees on the unused portion of the facility and fees with respect to issued and outstanding letters of credit. The applicable margins to the benchmark interest rates and certain fees fluctuate based on the credit ratings in effect from time to time on MPLX’s long-term debt.
The MPLX Credit Agreement contains certain representations and warranties, affirmative and restrictive covenants and events of default that MPLX considers to be usual and customary for an agreement of this type, including a financial covenant that requires MPLX to maintain a ratio of Consolidated Total Debt as of the end of each fiscal quarter to Consolidated EBITDA (both as defined in the MPLX Credit Agreement) for the prior four fiscal quarters of no greater than 5.0 to 1.0 (or 5.5 to 1.0 for up to two fiscal quarters following certain acquisitions). Consolidated EBITDA is subject to adjustments, including for certain acquisitions and dispositions completed and capital projects undertaken during the relevant period. Other covenants restrict MPLX and/or certain of its subsidiaries from incurring debt, creating liens on our assets and entering into transactions with affiliates. As of December 31, 2025, MPLX was in compliance with the covenants contained in the MPLX Credit Agreement.
Activity on the MPLX Credit Agreement during the year ended December 31, 2025 is summarized in the table below. There were no revolver borrowings or repayments under the MPLX Credit Agreement during the year ended December 31, 2024.
(in millions, except %)2025
Borrowings$106 
Weighted average interest rate of borrowings7.74 %
Repayments$106 
Outstanding balance at end of period$— 
Letters of credit outstanding$0.2 
Total remaining availability on facility$2,000 
Percent of borrowing capacity available100 %
Senior Notes
Interest on each series of MPLX LP and ANDX senior notes outstanding is payable semi-annually in arrears, according to the table below.
Senior NotesInterest payable semi-annually in arrears
1.750% senior notes due March 1, 2026
March 1st and September 1st
4.125% senior notes due March 1, 2027
March 1st and September 1st
4.250% senior notes due December 1, 2027
June 1st and December 1st
4.000% senior notes due March 15, 2028
March 15th and September 15th
4.800% senior notes due February 15, 2029
February 15th and August 15th
2.650% senior notes due August 15, 2030
February 15th and August 15th
4.800% senior notes due February 15, 2031
February 15th and August 15th
4.950% senior notes due September 1, 2032
March 1st and September 1st
5.000% senior notes due January 15, 2033
January 15th and July 15th
5.000% senior notes due March 1, 2033
March 1st and September 1st
5.500% senior notes due June 1, 2034
June 1st and December 1st
5.400% senior notes due April 1, 2035
April 1st and October 1st
5.400% senior notes due September 15, 2035
March 15th and September 15th
4.500% senior notes due April 15, 2038
April 15th and October 15th
5.200% senior notes due March 1, 2047
March 1st and September 1st
5.200% senior notes due December 1, 2047
June 1st and December 1st
4.700% senior notes due April 15, 2048
April 15th and October 15th
5.500% senior notes due February 15, 2049
February 15th and August 15th
4.950% senior notes due March 14, 2052
March 14th and September 14th
5.650% senior notes due March 1, 2053
March 1st and September 1st
5.950% senior notes due April 1, 2055
April 1st and October 1st
6.200% senior notes due September 15, 2055
March 15th and September 15th
4.900% senior notes due April 15, 2058
April 15th and October 15th
The following table summarizes debt issuances during the year ended December 31, 2025, all of which were issued in an underwritten public offering:
Issue DateAggregate Principal Amount
(in millions)		NoteCoupon (percent)Price to Public
(percent of par)		Interest Payment DatesMaturity Date
March 10, 2025$1,000 
(1)
5.40099.398April 1 and October 1April 1, 2035
March 10, 20251,000 
(1)
5.95098.331April 1 and October 1April 1, 2055
August 11, 20251,250 
(2)
4.80099.880February 15 and August 15February 15, 2031
August 11, 2025750 
(2)
5.00098.936January 15 and July 15January 15, 2033
August 11, 20251,500 
(2)
5.40098.943March 15 and September 15September 15, 2035
August 11, 20251,000 
(2)
6.20098.277March 15 and September 15September 15, 2055
(1)    On April 9, 2025, MPLX used $1.2 billion of the net proceeds from the issuance of senior notes in March 2025 to redeem all of (i) MPLX’s outstanding $1,189 million aggregate principal amount of 4.875 percent senior notes due June 2025 and (ii) MarkWest’s outstanding $11 million aggregate principal amount of 4.875 percent senior notes due June 2025. The remaining net proceeds from this offering were used for general partnership purposes.
(2)    We used a portion of the net proceeds from this offering to fund the Northwind Midstream Acquisition, including the payment of related fees and expenses, and to increase cash and cash equivalents following the recently completed BANGL Acquisition and BANGL Debt Repayment. The remainder of the net proceeds from this offering were used for general partnership purposes.
On July 3, 2025, MPLX used cash on hand to extinguish approximately $656 million principal amount of debt outstanding, including interest, related to certain term and revolving loans assumed as part of the BANGL Acquisition. See Note 4 for additional information on the BANGL Acquisition.
On May 20, 2024, MPLX issued $1.65 billion aggregate principal amount of 5.50 percent senior notes due June 2034 (the “2034 Senior Notes”) in an underwritten public offering. The 2034 Senior Notes were offered at a price to the public of 98.778 percent of par, with interest payable semi-annually in arrears, commencing on December 1, 2024. On December 1, 2024, MPLX used $1,150 million of the net proceeds from the issuance of the 2034 Senior Notes to repay all of (i) MPLX’s outstanding $1,149 million aggregate principal amount of 4.875 percent senior notes due December 2024 and (ii) MarkWest’s outstanding $1 million aggregate principal amount of 4.875 percent senior notes due December 2024. On February 18, 2025, MPLX used the
remaining net proceeds from the issuance of the 2034 Senior Notes to repay all of MPLX’s outstanding $500 million aggregate principal amount of 4.000 percent senior notes due February 2025.
Subordination of Senior Notes
The MPLX senior notes are direct, unsecured unsubordinated obligations of MPLX LP. As such, they rank equally in right of payment with all of MPLX LP’s other unsubordinated debt and are not guaranteed by any of MPLX LP’s subsidiaries. The MPLX notes are effectively junior to MPLX LP’s secured indebtedness, if any, to the extent of the value of the relevant collateral. The MPLX notes are not obligations of any of MPLX’s subsidiaries and are effectively subordinated to all indebtedness and other obligations of such subsidiaries. The MPLX notes may be redeemed, in whole or part, at any time at the option of MPLX at a redemption price specified in the indenture governing the applicable notes, plus accrued and unpaid interest to the redemption date. The indenture governing the MPLX senior notes does not limit the amount of debt that MPLX may issue under the indenture, nor the amount of other debt that MPLX or any of its subsidiaries may issue or guaranty.
The ANDX senior notes are non-recourse to MPLX and its subsidiaries other than ANDX, the general partner of ANDX and other subsidiaries, if any, of ANDX that are a co-issuer or guarantor of the ANDX senior notes.
v3.25.4
Net Interest and Other Financial Costs
 12 Months Ended
Dec. 31, 2025
Other Income and Expenses [Abstract]  
Net Interest and Other Financing Costs Net Interest and Other Financial Costs
Net interest and other financial costs were as follows:
(In millions)202520242023
Interest expense$1,072 $963 $912 
Other financial costs21 72 69 
Interest income(68)(95)(43)
Capitalized interest(42)(19)(15)
Net interest and other financial costs$983 $921 $923 
v3.25.4
Revenue
 12 Months Ended
Dec. 31, 2025
Revenue from Contract with Customer [Abstract]  
Revenue from Contract with Customer [Text Block] Revenue
Disaggregation of Revenue
The following tables represent a disaggregation of revenue for each reportable segment for the years ended December 31, 2025, 2024 and 2023:
2025
(In millions)Crude Oil and Products LogisticsNatural Gas and NGL ServicesTotal
Revenues and other income:
Service revenue$453 $2,446 $2,899 
Service revenue - related parties4,371 22 4,393 
Service revenue - product related— 289 289 
Product sales4 1,998 2,002 
Product sales - related parties12 131 143 
Total revenues from contracts with customers$4,840 $4,886 9,726 
Non-ASC 606 revenue and other income(1)
3,272 
Total revenues and other income$12,998 
2024
(In millions)Crude Oil and Products LogisticsNatural Gas and NGL ServicesTotal
Revenues and other income:
Service revenue$391 $2,379 $2,770 
Service revenue - related parties4,152 28 4,180 
Service revenue - product related— 357 357 
Product sales5 1,652 1,657 
Product sales - related parties13 212 225 
Total revenues from contracts with customers$4,561 $4,628 9,189 
Non-ASC 606 revenue and other income(1)
2,744 
Total revenues and other income$11,933 
2023
(In millions)Crude Oil and Products LogisticsNatural Gas and NGL ServicesTotal
Revenues and other income:
Service revenue$369 $2,170 $2,539 
Service revenue - related parties3,966 19 3,985 
Service revenue - product related— 294 294 
Product sales5 1,660 1,665 
Product sales - related parties13 237 250 
Total revenues from contracts with customers$4,353 $4,380 8,733 
Non-ASC 606 revenue and other income(1)
2,548 
Total revenues and other income$11,281 
(1)    Non-ASC 606 Revenue and other income includes rental income, sales-type lease revenue, income from equity method investments and other income.
Contract Balances
Our receivables are primarily associated with customer contracts. Payment terms vary by product or service type; however, the period between invoicing and payment is not significant. Included within the receivables are balances related to commodity sales on behalf of our producer customers, for which we remit the net sales price back to the producer customers upon completion of the sale.
Under certain contracts, we recognize revenues in excess of billings, which we present as contract assets. Contract assets typically relate to deficiency payments related to minimum volume commitments and aid in construction agreements where the revenue recognized and MPLX’s rights to consideration for work completed exceeds the amount billed to the customer. Contract assets are included in Other current assets and Other noncurrent assets on the Consolidated Balance Sheets.
Under certain contracts, we receive payments in advance of satisfying our performance obligations, which are recorded as contract liabilities. Contract liabilities, which are presented as Deferred revenue and Long-term deferred revenue, typically relate to advance payments for aid in construction agreements and deferred customer credits associated with makeup rights and minimum volume commitments. Breakage related to minimum volume commitments is estimated and recognized into service revenue in instances where it is probable the customer will not use the credit in future periods. We classify contract liabilities as current or long-term based on the timing of when we expect to recognize revenue.
The tables below reflect the changes in ASC 606 contract balances for the years ended December 31, 2025 and 2024:
(In millions)Balance at December 31, 2024Additions/ (Deletions)
Revenue Recognized(2)
Balance at December 31, 2025
Contract assets$2 $13 $— $15 
Long-term contract assets— 4 — 4 
Deferred revenue84 9 (80)13 
Deferred revenue - related parties71 86 (91)66 
Long-term deferred revenue(1)
315 (198)— 117 
Long-term deferred revenue - related parties44 1 — 45 
(In millions)Balance at December 31, 2023Additions/ (Deletions)
Revenue Recognized(2)
Balance at December 31, 2024
Contract assets$3 $— $(1)$2 
Long-term contract assets1 (1)— — 
Deferred revenue59 86 (61)84 
Deferred revenue - related parties47 90 (66)71 
Long-term deferred revenue344 (29)— 315 
Long-term deferred revenue - related parties29 15 — 44 
(1)    Long-term deferred revenue deletions include $180 million removed in connection with the Rockies divestiture. See Note 4 for additional information related to the Rockies divestiture.
(2)    No significant revenue was recognized related to past performance obligations in the period presented.
Remaining Performance Obligations
The table below includes estimated revenue expected to be recognized in the future related to performance obligations that are unsatisfied (or partially unsatisfied) as of December 31, 2025. The amounts presented below are generally limited to fixed consideration from contracts with customers that contain minimum volume commitments.
A significant portion of our future contracted revenue is excluded from the amounts presented below in accordance with ASC 606. Variable consideration that is constrained or not required to be estimated as it reflects our efforts to perform is excluded from this disclosure. Additionally, we do not disclose information on the future performance obligations for any contract with an original expected duration of one year or less, or that are terminable by our customer with little or no termination penalties. Potential future performance obligations related to renewals that have not yet been exercised or are not certain of exercise are excluded from the amounts presented below. Revenues classified as Rental income and Sales-type lease revenue are also excluded from this table as they are disclosed in Note 21.
(In billions)
2026$2.0 
20271.9 
20280.7 
20290.3 
20300.2 
2031 and thereafter0.7 
Total revenue on remaining performance obligations$5.8 
As of December 31, 2025, unsatisfied performance obligations included in the Consolidated Balance Sheets are $241 million and will be recognized as revenue as the obligations are satisfied, which is generally expected to occur over the next 20 years. A portion of this amount is not disclosed in the table above as it is deemed variable consideration due to volume variability.
v3.25.4
Supplemental Cash Flow Information
 12 Months Ended
Dec. 31, 2025
Supplemental Cash Flow Information [Abstract]  
Supplemental Cash Flow Information Supplemental Cash Flow Information
(In millions)202520242023
Net cash provided by operating activities included:
Interest paid (net of amounts capitalized)$913 $940 $893 
Income taxes paid7 6 7 
Cash paid for amounts included in the measurement of lease liabilities:
Payments on operating leases64 71 71 
Net cash provided by financing activities included:
Principal payments under finance lease obligations2 1 1 
Non-cash investing and financing activities:
Net transfers of property, plant and equipment to materials and supplies inventories— — (8)
Contribution of assets(1)
115 — — 
ROU assets obtained in exchange for new operating lease obligations53 47 21 
ROU assets obtained in exchange for new finance lease obligations3 1 — 
Book value of equity method investment(2)
282 4 311 
Contingent consideration(3)
234 — — 
Other24 — — 
(1)    Represents the book value of assets contributed by MPLX to a joint venture.
(2)    Represents the book value of MPLX’s equity method investment in BANGL in 2025, OCC in 2024 and Torñado in 2023 prior to MPLX buying out the remaining interest in these entities. See Note 4 for additional information.
(3)    See Note 4 – BANGL, LLC Acquisitions.
The Consolidated Statements of Cash Flows exclude changes to the Consolidated Balance Sheets that did not affect cash. The following is a reconciliation of additions to property, plant and equipment to total capital expenditures:
(In millions)202520242023
Additions to property, plant and equipment$1,808 $1,056 $937 
Increase/(decrease) in capital accruals170 (6)82 
Other(22)— — 
Total capital expenditures$1,956 $1,050 $1,019 
v3.25.4
Leases (Notes)
 12 Months Ended
Dec. 31, 2025
Leases [Abstract]  
Lessee, Operating Leases
Lessee
We lease a wide variety of facilities and equipment under leases from third parties, including land and building space, office and field equipment, storage facilities and transportation equipment, while our related party leases primarily relate to ground leases associated with our refining logistics assets. Our remaining lease terms range from less than one year to 93 years. Some long-term leases include renewal options ranging from one year to 50 years and, in certain leases, also include purchase options. Renewal options and termination options were not included in the measurement of ROU assets and lease liabilities since it was determined they were not reasonably certain to be exercised.
The components of lease cost were as follows:
202520242023
(In millions)Related PartyThird
Party		Related
Party		Third
Party		Related
Party		Third
Party
Components of lease costs:
Operating lease costs$15 $60 $14 $58 $14 $56 
Finance lease cost:
Amortization of ROU assets— 2 — 1 — 1 
Interest on lease liabilities — 1 — — — — 
Total finance lease cost— 3 — 1 — 1 
Variable lease cost4 14 4 12 4 10 
Short-term lease cost1 70 1 71 1 61 
Total lease cost$20 $147 $19 $142 $19 $128 
Supplemental balance sheet data related to leases were as follows:
December 31, 2025December 31, 2024
(In millions, except % and years)Related PartyThird PartyRelated PartyThird Party
Operating leases
Assets
Right of use assets$239 $276 $226$273
Liabilities
Operating lease liabilities2 53 245
Long-term operating lease liabilities237 217 224217
Total operating lease liabilities$239 $270 $226$262
Weighted average remaining lease term40 years7 years42 years8 years
Weighted average discount rate5.8 %4.3 %5.8 %4.2 %
Finance leases
Assets
Property, plant and equipment, gross$12 $10
Less: Accumulated depreciation6 5
Property, plant and equipment, net6 5
Liabilities
Long-term debt due within one year2 1
Long-term debt4 5
Total finance lease liabilities$6 $6
Weighted average remaining lease term21 years22 years
Weighted average discount rate5.8 %6.0 %
As of December 31, 2025, maturities of lease liabilities for operating lease obligations and finance lease obligations having initial or remaining non-cancellable lease terms in excess of one year are as follows:
(In millions)Related Party Operating
Leases		Third Party Operating
Leases 		Finance
Leases
2026$16 $62 $3 
202716 54 2 
202816 47 — 
202915 36 — 
203015 28 — 
2031 and thereafter537 84 7 
Gross lease payments615 311 12 
Less: Imputed interest376 41 6 
Total lease liabilities$239 $270 $6 
Lessee, Finance Leases
Lessee
We lease a wide variety of facilities and equipment under leases from third parties, including land and building space, office and field equipment, storage facilities and transportation equipment, while our related party leases primarily relate to ground leases associated with our refining logistics assets. Our remaining lease terms range from less than one year to 93 years. Some long-term leases include renewal options ranging from one year to 50 years and, in certain leases, also include purchase options. Renewal options and termination options were not included in the measurement of ROU assets and lease liabilities since it was determined they were not reasonably certain to be exercised.
The components of lease cost were as follows:
202520242023
(In millions)Related PartyThird
Party		Related
Party		Third
Party		Related
Party		Third
Party
Components of lease costs:
Operating lease costs$15 $60 $14 $58 $14 $56 
Finance lease cost:
Amortization of ROU assets— 2 — 1 — 1 
Interest on lease liabilities — 1 — — — — 
Total finance lease cost— 3 — 1 — 1 
Variable lease cost4 14 4 12 4 10 
Short-term lease cost1 70 1 71 1 61 
Total lease cost$20 $147 $19 $142 $19 $128 
Supplemental balance sheet data related to leases were as follows:
December 31, 2025December 31, 2024
(In millions, except % and years)Related PartyThird PartyRelated PartyThird Party
Operating leases
Assets
Right of use assets$239 $276 $226$273
Liabilities
Operating lease liabilities2 53 245
Long-term operating lease liabilities237 217 224217
Total operating lease liabilities$239 $270 $226$262
Weighted average remaining lease term40 years7 years42 years8 years
Weighted average discount rate5.8 %4.3 %5.8 %4.2 %
Finance leases
Assets
Property, plant and equipment, gross$12 $10
Less: Accumulated depreciation6 5
Property, plant and equipment, net6 5
Liabilities
Long-term debt due within one year2 1
Long-term debt4 5
Total finance lease liabilities$6 $6
Weighted average remaining lease term21 years22 years
Weighted average discount rate5.8 %6.0 %
As of December 31, 2025, maturities of lease liabilities for operating lease obligations and finance lease obligations having initial or remaining non-cancellable lease terms in excess of one year are as follows:
(In millions)Related Party Operating
Leases		Third Party Operating
Leases 		Finance
Leases
2026$16 $62 $3 
202716 54 2 
202816 47 — 
202915 36 — 
203015 28 — 
2031 and thereafter537 84 7 
Gross lease payments615 311 12 
Less: Imputed interest376 41 6 
Total lease liabilities$239 $270 $6 
Lessor, Operating Leases
Lessor
Certain fee-based transportation and storage services agreements with MPC and third parties and certain fee-based natural gas transportation and processing agreements with third parties are accounted for as operating leases under ASC 842. These agreements have remaining terms ranging from less than one year to 20 years with renewal options ranging from one year to five years, with some agreements having multiple renewal options.
MPLX did not elect to use the practical expedient to combine lease and non-lease components for lessor arrangements. The tables below represent the portion of the contract allocated to the lease component based on relative standalone selling price. We elected the practical expedient to carry forward historical classification conclusions until a modification of an existing agreement occurs. Once a modification occurs, the amended agreement is required to be assessed under ASC 842, to determine whether a reclassification of the lease is required.
Lease revenues included on the Consolidated Statements of Income during 2025, 2024 and 2023 were as follows:
202520242023
(In millions)Related PartyThird
Party		Related PartyThird
Party		Related PartyThird
Party
Operating leases:
Rental income$889 $260 $853 $251 $822 $243 
Sales-type leases:
Interest income (Sales-type rental revenue - fixed minimum)431 113 455 114 467 114 
Interest income (Revenue from variable lease payments)17 38 20 22 33 22 
Sales-type lease revenue$448 $151 $475 $136 $500 $136 
There were no significant sales-type lease commencements or modifications during the periods presented which resulted in additional lease receivables.
The following is a schedule of minimum future rental payments to be received on the non-cancellable operating leases as of December 31, 2025:
(In millions)Related PartyThird PartyTotal
2026$835 $107 $942 
2027721 80 801 
2028418 73 491 
2029264 71 335 
2030254 58 312 
2031 and thereafter519 182 701 
Total minimum future rentals$3,011 $571 $3,582 
Annual minimum undiscounted lease payment receipts under our sales-type leases were as follows as of December 31, 2025:
(In millions)Related PartyThird PartyTotal
2026$472 $181 $653 
2027390 163 553 
2028109 154 263 
202956 146 202 
203056 138 194 
2031 and thereafter63 903 966 
Total minimum future rentals 1,146 1,685 2,831 
Less: Imputed interest456 691 1,147 
Lease receivable(1)
$690 $994 $1,684 
Current lease receivables(2)
$269 $108 $377 
Long-term lease receivables(3)
421 886 1,307 
Unguaranteed residual assets(3)
263 117 380 
Total sales-type lease assets$953 $1,111 $2,064 
(1)    This amount does not include the unguaranteed residual assets.
(2)    The related-party balance is presented in Current assets - related parties and the third-party balance is presented in Receivables, net in the Consolidated Balance Sheets.
(3)    The related-party balance is presented in Noncurrent assets - related parties and the third-party balance is presented in Other noncurrent assets in the Consolidated Balance Sheets.
The following schedule summarizes MPLX’s investment in assets held under operating lease by major classes as of December 31, 2025 and 2024:
December 31,
(In millions)20252024
Pipelines$681 $689 
Refining logistics1,774 1,430 
Terminals1,440 1,310 
Marine126 126 
Gathering and transportation111 86 
Processing and fractionation1,017 1,039 
Land, building and other161 171 
Total property, plant and equipment5,310 4,851 
Less: accumulated depreciation2,731 2,378 
Property, plant and equipment, net$2,579 $2,473 
Capital expenditures related to assets subject to sales-type lease arrangements were $221 million, $159 million and $85 million for the years ended December 31, 2025, 2024 and 2023, respectively. These amounts are reflected as Additions to property, plant and equipment in the Consolidated Statements of Cash Flows.
Lessor, Sales-type Leases
Lessor
Certain fee-based transportation and storage services agreements with MPC and third parties and certain fee-based natural gas transportation and processing agreements with third parties are accounted for as operating leases under ASC 842. These agreements have remaining terms ranging from less than one year to 20 years with renewal options ranging from one year to five years, with some agreements having multiple renewal options.
MPLX did not elect to use the practical expedient to combine lease and non-lease components for lessor arrangements. The tables below represent the portion of the contract allocated to the lease component based on relative standalone selling price. We elected the practical expedient to carry forward historical classification conclusions until a modification of an existing agreement occurs. Once a modification occurs, the amended agreement is required to be assessed under ASC 842, to determine whether a reclassification of the lease is required.
Lease revenues included on the Consolidated Statements of Income during 2025, 2024 and 2023 were as follows:
202520242023
(In millions)Related PartyThird
Party		Related PartyThird
Party		Related PartyThird
Party
Operating leases:
Rental income$889 $260 $853 $251 $822 $243 
Sales-type leases:
Interest income (Sales-type rental revenue - fixed minimum)431 113 455 114 467 114 
Interest income (Revenue from variable lease payments)17 38 20 22 33 22 
Sales-type lease revenue$448 $151 $475 $136 $500 $136 
There were no significant sales-type lease commencements or modifications during the periods presented which resulted in additional lease receivables.
The following is a schedule of minimum future rental payments to be received on the non-cancellable operating leases as of December 31, 2025:
(In millions)Related PartyThird PartyTotal
2026$835 $107 $942 
2027721 80 801 
2028418 73 491 
2029264 71 335 
2030254 58 312 
2031 and thereafter519 182 701 
Total minimum future rentals$3,011 $571 $3,582 
Annual minimum undiscounted lease payment receipts under our sales-type leases were as follows as of December 31, 2025:
(In millions)Related PartyThird PartyTotal
2026$472 $181 $653 
2027390 163 553 
2028109 154 263 
202956 146 202 
203056 138 194 
2031 and thereafter63 903 966 
Total minimum future rentals 1,146 1,685 2,831 
Less: Imputed interest456 691 1,147 
Lease receivable(1)
$690 $994 $1,684 
Current lease receivables(2)
$269 $108 $377 
Long-term lease receivables(3)
421 886 1,307 
Unguaranteed residual assets(3)
263 117 380 
Total sales-type lease assets$953 $1,111 $2,064 
(1)    This amount does not include the unguaranteed residual assets.
(2)    The related-party balance is presented in Current assets - related parties and the third-party balance is presented in Receivables, net in the Consolidated Balance Sheets.
(3)    The related-party balance is presented in Noncurrent assets - related parties and the third-party balance is presented in Other noncurrent assets in the Consolidated Balance Sheets.
The following schedule summarizes MPLX’s investment in assets held under operating lease by major classes as of December 31, 2025 and 2024:
December 31,
(In millions)20252024
Pipelines$681 $689 
Refining logistics1,774 1,430 
Terminals1,440 1,310 
Marine126 126 
Gathering and transportation111 86 
Processing and fractionation1,017 1,039 
Land, building and other161 171 
Total property, plant and equipment5,310 4,851 
Less: accumulated depreciation2,731 2,378 
Property, plant and equipment, net$2,579 $2,473 
Capital expenditures related to assets subject to sales-type lease arrangements were $221 million, $159 million and $85 million for the years ended December 31, 2025, 2024 and 2023, respectively. These amounts are reflected as Additions to property, plant and equipment in the Consolidated Statements of Cash Flows.
v3.25.4
Commitments and Contingencies
 12 Months Ended
Dec. 31, 2025
Commitments and Contingencies Disclosure [Abstract]  
Commitments and Contingencies Commitments and Contingencies
MPLX is the subject of, or a party to, a number of pending or threatened legal actions, contingencies and commitments involving a variety of matters, including laws and regulations relating to the environment. Some of these matters are discussed below. For matters for which MPLX has not recorded a liability, MPLX is unable to estimate a range of possible loss because the issues involved have not been fully developed through pleadings, discovery or court proceedings. However, the ultimate resolution of some of these contingencies could, individually or in the aggregate, be material.
Environmental Matters
MPLX is subject to federal, state and local laws and regulations relating to the environment. These laws generally provide for control of pollutants released into the environment and require responsible parties to undertake remediation of hazardous waste disposal sites. Penalties may be imposed for non-compliance.
At December 31, 2025 and 2024, accrued liabilities for remediation totaled $21 million and $15 million, respectively. It is not presently possible to estimate the ultimate amount of all remediation costs that might be incurred or the penalties, if any, that may be imposed.
MPLX is involved in environmental enforcement matters arising in the ordinary course of business. While the outcome and impact to MPLX cannot be predicted with certainty, management believes the resolution of these environmental matters will not, individually or collectively, have a material adverse effect on its consolidated results of operations, financial position or cash flows.
Other Legal Proceedings
Tesoro High Plains Pipeline
In July 2020, Tesoro High Plains Pipeline Company, LLC (“THPP”), a subsidiary of MPLX, received a Notification of Trespass Determination from the Bureau of Indian Affairs (“BIA”) relating to a portion of the Tesoro High Plains Pipeline. The notification demanded the immediate cessation of pipeline operations and assessed trespass damages of approximately $187 million. After subsequent appeal proceedings and in compliance with a new order issued by the BIA, THPP paid approximately $4 million in assessed trespass damages and ceased use of the portion of the pipeline that crosses the property at issue. In March 2021, the BIA issued an order purporting to vacate the BIA's prior orders related to THPP’s alleged trespass and directed the Regional Director of the BIA to reconsider the issue of THPP’s alleged trespass and issue a new order. In April 2021, THPP filed a lawsuit in the District of North Dakota against the United States of America, the U.S. Department of the Interior and the BIA (collectively, the “U.S. Government Parties”) challenging the March 2021 order purporting to vacate all previous orders related to THPP’s alleged trespass. The case will proceed on the merits of THPP’s challenge to the March 2021 order purporting to vacate all previous orders related to THPP’s alleged trespass.
MPLX is also a party to a number of other lawsuits and other proceedings arising in the ordinary course of business. While the ultimate outcome and impact to MPLX cannot be predicted with certainty, management believes the resolution of these other lawsuits and proceedings will not, individually or collectively, have a material adverse effect on its consolidated financial position, results of operations or cash flows.
Guarantees
Over the years, MPLX has sold various assets in the normal course of its business. Certain of the related agreements contain performance and general guarantees, including guarantees regarding inaccuracies in representations, warranties, covenants and agreements, and environmental and general indemnifications that require MPLX to perform upon the occurrence of a triggering event or condition. These guarantees and indemnifications are part of the normal course of selling assets. MPLX is typically not able to calculate the maximum potential amount of future payments that could be made under such contractual provisions because of the variability inherent in the guarantees and indemnities. Most often, the nature of the guarantees and indemnities is such that there is no appropriate method for quantifying the exposure because the underlying triggering event has little or no past experience upon which a reasonable prediction of the outcome can be based.
Dakota Access Pipeline
We hold a 9.19 percent indirect interest in Dakota Access, which owns and operates the Bakken Pipeline system. In 2020, the U.S. District Court for the District of Columbia (the “D.D.C.”) ordered the United States Army Corps of Engineers (“Army Corps”), which granted permits and an easement for the Bakken Pipeline system, to prepare an environmental impact statement (“EIS”) relating to an easement under Lake Oahe in North Dakota. The D.D.C. later vacated the easement. The Army Corps issued the final EIS in late 2025 and recommended the continued operation of the pipeline. The Army Corps may issue a Record of Decision now that the final EIS has been issued. New litigation may be filed now that the final EIS has been issued.
We have entered into a Contingent Equity Contribution Agreement whereby MPLX LP, along with the other joint venture owners in the Bakken Pipeline system, has agreed to make equity contributions to the joint venture upon certain events occurring to allow the entities that own and operate the Bakken Pipeline system to satisfy their senior note payment obligations.
If the vacatur of the easement results in a temporary shutdown of the pipeline, MPLX would have to contribute its 9.19 percent pro rata share of funds required to pay interest accruing on the notes and any portion of the principal that matures while the pipeline is shut down. MPLX also expects to contribute its 9.19 percent pro rata share of any costs to remediate any deficiencies to reinstate the easement and/or return the pipeline into operation. If the vacatur of the easement results in a permanent shutdown of the pipeline, MPLX would have to contribute its 9.19 percent pro rata share of the cost to redeem the bonds (including the one percent redemption premium required pursuant to the indenture governing the notes) and any accrued and unpaid interest. As of December 31, 2025, our maximum potential undiscounted payments under the Contingent Equity Contribution Agreement were approximately $78 million.
WPC Parent, LLC
MPLX’s maximum exposure to loss for WPC Parent, LLC includes an $109 million commitment to indemnify a joint venture member for our pro rata share of any payments made under a performance guarantee for construction of a pipeline by an equity method investee.
Contractual Commitments and Contingencies
At December 31, 2025, MPLX’s contractual commitments to acquire property, plant and equipment totaled $311 million. In addition, from time to time and in the ordinary course of business, MPLX and its affiliates provide guarantees of MPLX’s
subsidiaries’ payment and performance obligations in the Natural Gas and NGL Services segment. Certain natural gas processing and gathering arrangements require MPLX to construct new natural gas processing plants, natural gas gathering pipelines and NGL pipelines and contain certain fees and charges if specified construction milestones are not achieved for reasons other than force majeure. In certain cases, certain producers may have the right to cancel the processing arrangements if there are significant delays that are not due to force majeure. As of December 31, 2025, management does not believe there are any indications that MPLX will not be able to meet the construction milestones, that force majeure does not apply or that such fees and charges will otherwise be triggered.
Other Contractual Obligations
MPLX executed various third-party transportation, terminalling, and gathering and processing agreements that obligate us to minimum volume, throughput or payment commitments over the remaining terms, which range from less than one year to seven years. After the minimum volume commitments are met in these agreements, MPLX pays additional amounts based on throughput. These agreements may include escalation clauses based on various inflationary indices; however, those potential increases have not been incorporated in minimum fees due under these agreements presented below. The minimum future payments under these agreements as of December 31, 2025 are as follows:
(In millions)
2026$163 
2027146 
2028132 
202946 
203012 
2031 and thereafter10 
Total$509 
v3.25.4
Subsequent Events
 12 Months Ended
Dec. 31, 2025
Subsequent Events [Abstract]  
Subsequent Events Subsequent Event
On February 12, 2026, MPLX issued $1.0 billion aggregate principal amount of 5.30 percent senior notes due 2036 (the “2036 Senior Notes”) and $500 million aggregate principal amount of 6.10 percent senior notes due 2056 (the “2056 Senior Notes”) in an underwritten public offering. The 2036 Senior Notes were offered at a price to the public of 99.678 percent of par, with interest payable semi-annually in arrears, commencing on October 1, 2026. The 2056 Senior Notes were offered at a price to the public of 98.453 percent of par, with interest payable semi-annually in arrears, commencing on October 1, 2026. We intend to use the net proceeds from the 2036 Senior Notes and 2056 Senior Notes to repay MPLX’s outstanding $1,500 million aggregate principal amount of 1.750 percent senior notes due March 2026 at maturity. Pending final use, we may invest the proceeds in short-term marketable securities or other investments.
v3.25.4
Insider Trading Arrangements
 3 Months Ended
Dec. 31, 2025
Trading Arrangements, by Individual  
Material Terms of Trading Arrangement
During the quarter ended December 31, 2025, no director or officer (as defined in Rule 16a-1(f) promulgated under the Exchange Act) of MPLX adopted or terminated a “Rule 10b5-1 trading arrangement” or “non-Rule 10b5-1 trading arrangement” (as each term is defined in Item 408 of Regulation S-K).
Rule 10b5-1 Arrangement Adopted false
Non-Rule 10b5-1 Arrangement Adopted false
Rule 10b5-1 Arrangement Terminated false
Non-Rule 10b5-1 Arrangement Terminated false
v3.25.4
Insider Trading Policies and Procedures
 12 Months Ended
Dec. 31, 2025
Insider Trading Policies and Procedures [Line Items]  
Insider Trading Policies and Procedures Adopted true
v3.25.4
Cybersecurity Risk Management and Strategy Disclosure
 12 Months Ended
Dec. 31, 2025
Cybersecurity Risk Management, Strategy, and Governance [Line Items]  
Cybersecurity Risk Management Processes for Assessing, Identifying, and Managing Threats [Text Block]
Risk Management and Strategy
MPC has processes in place designed to protect our information systems, data, assets, infrastructure and computing environments from cybersecurity threats and risks while maintaining confidentiality, integrity, and availability. These enterprise-wide processes are based upon policies, practices and standards that guide MPC on identifying, assessing, and managing material risks from cybersecurity threats and include, but are not limited to:
•placing security limits on physical and network access to our information technology (“IT”) and operating technology (“OT”) systems;
•employing internal IT and OT controls designed to detect cybersecurity threats by collecting and analyzing data in MPC’s centralized cybersecurity operations center;
•utilizing layers of defensive methodologies designed to facilitate cyber resilience, minimize attack surfaces, and provide flexibility and scalability in MPC’s ability to address cybersecurity risks and threats;
•providing cybersecurity threat and awareness training to employees and contractors;
•limiting remote network access to our IT and OT network environments; and
•assessing our cybersecurity resiliency through various methods, including penetration testing, tabletop exercises with varying scenarios and participants ranging from individuals on our operations teams to executive leadership, and analyzing our corporate cybersecurity incident response plan.
MPC applies an enterprise risk management (“ERM”) methodology as established and led by the MPC and MPLX GP executive leadership team and overseen by the Board to identify, assess, and manage enterprise-level risks. MPC’s cybersecurity risk program directly integrates and is intended to align with MPC’s governing ERM program.
MPC engages with external resources to contribute to and provide independent evaluation of its cybersecurity practices, including a periodic assessment of its cybersecurity program that is performed by a third party. MPC’s cybersecurity leadership and operational teams monitor cybersecurity threat intelligence and applicable cybersecurity regulatory requirements in a variety of ways, including by communicating with federal agencies, trade associations, service providers, and other miscellaneous third-party resources. MPLX GP’s management team, through consultation with MPC’s Senior Vice President and Chief Digital Officer (“CDO”), Vice President and Chief Information Security Officer (“CISO”), and the MPLX GP Audit Committee of the MPLX GP Board, use the information gathered from these sources to inform long-term cybersecurity investments and strategies which seek to identify cybersecurity threats and protect against, detect, respond to and recover from cybersecurity incidents.
The information systems, data, assets, infrastructure, and computing environments of MPC’s third-party service providers are also at risk of cybersecurity incidents. MPC manages third-party service provider cybersecurity risks through contract management, evaluation of applicable security control assessments, and third-party risk assessment processes.
As of February 26, 2026, we do not believe that any risks from cybersecurity threats, including as a result of past cybersecurity incidents have had, or are reasonably likely to have, a material adverse effect on the Partnership, including our business strategy, results of operations, or financial condition. However, there can be no assurance that MPC’s cybersecurity processes will prevent or mitigate cybersecurity incidents or threats and that efforts will always be successful. It is possible that cybersecurity incidents may occur and could have a material adverse effect on our business strategy, results of operations, or financial condition. See “Business and Operational Risks--We are increasingly dependent on the performance of our information technology systems and those of our third-party business partners and service providers” in Item 1A. Risk Factors of this Annual Report on Form 10-K.
Governance
The full Board of Directors of MPLX GP oversees enterprise-level risks and in conjunction with the Audit Committee of the MPLX GP Board oversees risks from cybersecurity threats as informed through MPC’s ERM program. MPC’s CDO and CISO are standing members of the ERM committee, comprised of members of senior management, and as part of the committee, report on and evaluate cybersecurity threats and risk management efforts, as communicated to them by way of their direct reports and the larger cybersecurity team. The MPC CDO and CISO are responsible for assessing and managing risks from cybersecurity threats. The CDO and CISO provide regular cybersecurity briefings to the MPLX GP Board of Directors including the MPLX GP Audit Committee, with a minimum of two briefings per year and additional briefings as needed. The MPLX GP Audit Committee also has direct access to the CDO and CISO and their management teams for other updates on cybersecurity and information security strategy throughout the year. Additionally, the CDO and CISO, from time to time, meet with members of management to discuss cybersecurity risks, strategy and threats.
MPC’s CISO is responsible for implementing the cybersecurity program which is comprised of Cybersecurity GRC (Governance, Risk & Compliance), Cybersecurity Architecture, Engineering & Operations, and a Cyber Fusion Center that includes Threat Intelligence, Vulnerability Management, & Incident Response. MPC’s CISO has more than 30 years of experience in the oil and gas industry and has held various leadership and strategic roles related to information security and related technology, including collectively serving as a chief information security officer for seven years at two publicly traded companies. Its CISO also holds an Executive Master in Cybersecurity degree and a Master of Computer Science degree.
MPC’s CISO works at the direction of MPC’s CDO, who has more than 20 years of executive IT leadership experience and leads the company’s Digital and Information Technology functions that seek to provide innovative, secure, and reliable technology products and services to MPC and its customers. Prior to joining MPC in 2021, its CDO was employed by General Electric Company (“GE”) and its subsidiary companies for over 20 years, holding several executive IT leadership roles with increasing responsibility. He was then named Senior Vice President and Chief Information Officer of Services for parent company GE in 2017 and was later named the Vice President and Chief Information Officer of GE Healthcare. MPC’s CDO holds a Bachelor’s degree in Business Administration, Management and Information Systems.
Cybersecurity Risk Management Processes Integrated [Flag] true
Cybersecurity Risk Management Processes Integrated [Text Block] MPC applies an enterprise risk management (“ERM”) methodology as established and led by the MPC and MPLX GP executive leadership team and overseen by the Board to identify, assess, and manage enterprise-level risks. MPC’s cybersecurity risk program directly integrates and is intended to align with MPC’s governing ERM program.
Cybersecurity Risk Management Third Party Engaged [Flag] true
Cybersecurity Risk Third Party Oversight and Identification Processes [Flag] true
Cybersecurity Risk Materially Affected or Reasonably Likely to Materially Affect Registrant [Flag] false
Cybersecurity Risk Board of Directors Oversight [Text Block]
Governance
The full Board of Directors of MPLX GP oversees enterprise-level risks and in conjunction with the Audit Committee of the MPLX GP Board oversees risks from cybersecurity threats as informed through MPC’s ERM program. MPC’s CDO and CISO are standing members of the ERM committee, comprised of members of senior management, and as part of the committee, report on and evaluate cybersecurity threats and risk management efforts, as communicated to them by way of their direct reports and the larger cybersecurity team. The MPC CDO and CISO are responsible for assessing and managing risks from cybersecurity threats. The CDO and CISO provide regular cybersecurity briefings to the MPLX GP Board of Directors including the MPLX GP Audit Committee, with a minimum of two briefings per year and additional briefings as needed. The MPLX GP Audit Committee also has direct access to the CDO and CISO and their management teams for other updates on cybersecurity and information security strategy throughout the year. Additionally, the CDO and CISO, from time to time, meet with members of management to discuss cybersecurity risks, strategy and threats.
MPC’s CISO is responsible for implementing the cybersecurity program which is comprised of Cybersecurity GRC (Governance, Risk & Compliance), Cybersecurity Architecture, Engineering & Operations, and a Cyber Fusion Center that includes Threat Intelligence, Vulnerability Management, & Incident Response. MPC’s CISO has more than 30 years of experience in the oil and gas industry and has held various leadership and strategic roles related to information security and related technology, including collectively serving as a chief information security officer for seven years at two publicly traded companies. Its CISO also holds an Executive Master in Cybersecurity degree and a Master of Computer Science degree.
MPC’s CISO works at the direction of MPC’s CDO, who has more than 20 years of executive IT leadership experience and leads the company’s Digital and Information Technology functions that seek to provide innovative, secure, and reliable technology products and services to MPC and its customers. Prior to joining MPC in 2021, its CDO was employed by General Electric Company (“GE”) and its subsidiary companies for over 20 years, holding several executive IT leadership roles with increasing responsibility. He was then named Senior Vice President and Chief Information Officer of Services for parent company GE in 2017 and was later named the Vice President and Chief Information Officer of GE Healthcare. MPC’s CDO holds a Bachelor’s degree in Business Administration, Management and Information Systems.
Cybersecurity Risk Board Committee or Subcommittee Responsible for Oversight [Text Block] in conjunction with the Audit Committee of the MPLX GP Board oversees risks from cybersecurity threats as informed through MPC’s ERM program.
Cybersecurity Risk Process for Informing Board Committee or Subcommittee Responsible for Oversight [Text Block] MPC’s CDO and CISO are standing members of the ERM committee, comprised of members of senior management, and as part of the committee, report on and evaluate cybersecurity threats and risk management efforts, as communicated to them by way of their direct reports and the larger cybersecurity team. The MPC CDO and CISO are responsible for assessing and managing risks from cybersecurity threats. The CDO and CISO provide regular cybersecurity briefings to the MPLX GP Board of Directors including the MPLX GP Audit Committee, with a minimum of two briefings per year and additional briefings as needed. The MPLX GP Audit Committee also has direct access to the CDO and CISO and their management teams for other updates on cybersecurity and information security strategy throughout the year. Additionally, the CDO and CISO, from time to time, meet with members of management to discuss cybersecurity risks, strategy and threats.
Cybersecurity Risk Role of Management [Text Block] MPC’s CISO is responsible for implementing the cybersecurity program which is comprised of Cybersecurity GRC (Governance, Risk & Compliance), Cybersecurity Architecture, Engineering & Operations, and a Cyber Fusion Center that includes Threat Intelligence, Vulnerability Management, & Incident Response
Cybersecurity Risk Management Positions or Committees Responsible [Flag] true
Cybersecurity Risk Management Positions or Committees Responsible [Text Block] MPC’s CISO is responsible for implementing the cybersecurity program
Cybersecurity Risk Management Expertise of Management Responsible [Text Block] MPC’s CISO has more than 30 years of experience in the oil and gas industry and has held various leadership and strategic roles related to information security and related technology, including collectively serving as a chief information security officer for seven years at two publicly traded companies. Its CISO also holds an Executive Master in Cybersecurity degree and a Master of Computer Science degree.
MPC’s CISO works at the direction of MPC’s CDO, who has more than 20 years of executive IT leadership experience and leads the company’s Digital and Information Technology functions that seek to provide innovative, secure, and reliable technology products and services to MPC and its customers. Prior to joining MPC in 2021, its CDO was employed by General Electric Company (“GE”) and its subsidiary companies for over 20 years, holding several executive IT leadership roles with increasing responsibility. He was then named Senior Vice President and Chief Information Officer of Services for parent company GE in 2017 and was later named the Vice President and Chief Information Officer of GE Healthcare. MPC’s CDO holds a Bachelor’s degree in Business Administration, Management and Information Systems.
Cybersecurity Risk Process for Informing Management or Committees Responsible [Text Block] The MPC CDO and CISO are responsible for assessing and managing risks from cybersecurity threats. The CDO and CISO provide regular cybersecurity briefings to the MPLX GP Board of Directors including the MPLX GP Audit Committee, with a minimum of two briefings per year and additional briefings as needed. The MPLX GP Audit Committee also has direct access to the CDO and CISO and their management teams for other updates on cybersecurity and information security strategy throughout the year. Additionally, the CDO and CISO, from time to time, meet with members of management to discuss cybersecurity risks, strategy and threats.
Cybersecurity Risk Management Positions or Committees Responsible Report to Board [Flag] true
v3.25.4
Description of Business and Basis of Presentation (Policies)
 12 Months Ended
Dec. 31, 2025
Limited Liability Company or Limited Partnership, Business Organization and Operations [Abstract]  
Basis of presentation
Basis of Presentation
The accompanying consolidated financial statements of MPLX have been prepared in accordance with GAAP. The consolidated financial statements include all majority-owned and controlled subsidiaries. For non-wholly-owned consolidated subsidiaries, the interests owned by third parties have been recorded as Noncontrolling interests on the accompanying Consolidated Balance Sheets. Intercompany accounts and transactions have been eliminated. MPLX’s investments in which MPLX exercises significant influence but does not control and does not have a controlling financial interest are accounted for using the equity method. MPLX’s investments in VIEs, in which MPLX exercises significant influence but does not control and is not the primary beneficiary, are also accounted for using the equity method.
In the fourth quarter of 2024, we renamed and modified the composition of our segments to better reflect the product-based value chains and growth strategy of MPLX’s operations. Certain prior period financial statement amounts have been reclassified to conform to current period presentation.
v3.25.4
Summary of Principal Accounting Policies (Policies)
 12 Months Ended
Dec. 31, 2025
Accounting Policies [Abstract]  
Use of estimates
Use of Estimates
The preparation of financial statements in accordance with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities as of the date of the consolidated financial statements and the reported amounts of revenues and expenses during the respective reporting periods. Actual results could differ materially from those estimates. Estimates are subject to uncertainties due to the levels of subjectivity and judgment necessary to account for highly uncertain matters or the susceptibility of such matters to change and affect items such as valuing identified intangible assets; determining the fair value of derivative instruments; evaluating impairments of long-lived assets, goodwill and equity investments; establishing estimated useful lives for long-lived assets; acquisition accounting; estimating revenues, expense accruals and capital expenditures; valuing AROs; recognizing share-based compensation expense; and determining liabilities, if any, for environmental and legal contingencies.
Revenue recognition
Revenue Recognition
Revenue is measured based on consideration specified in a contract with a customer. MPLX recognizes revenue when it satisfies a performance obligation by transferring control over a product or providing services to a customer.
MPLX enters into a variety of contract types in order to generate Product sales and Service revenue. MPLX provides services under the following types of arrangements:
•Fee-based arrangements – Under fee-based arrangements, MPLX receives fees for the following services: gathering, treating, processing and transportation of natural gas; transportation, fractionation, exchange and storage of NGLs; and transportation, terminalling, storage and distribution of crude oil, refined products, other hydrocarbon-based products, and renewables. The revenue MPLX earns from these arrangements is generally directly related to the volume of natural gas, NGLs, refined products or crude oil that is handled by or flows through MPLX’s systems and facilities and is not normally directly dependent on commodity prices. In certain cases, MPLX’s arrangements provide for minimum volume commitments. Fee-based arrangements are reported as Service revenue on the Consolidated Statements of Income. Revenue is recognized over time as services are performed. In certain instances when specifically stated in the contract terms, MPLX purchases product after fee-based services have been provided. Revenue from the sale of products purchased after services are provided is reported as Product sales on the Consolidated Statements of Income and recognized on a gross basis, as MPLX takes control of the product and is the principal in the transaction.
•Percent-of-proceeds arrangements – Under percent-of-proceeds arrangements, MPLX gathers and processes natural gas on behalf of producers; sells the resulting residue gas, condensate and NGLs at market prices; and remits to producers an agreed-upon percentage of the proceeds. In other cases, instead of remitting cash payments to the
producer, MPLX delivers an agreed-upon percentage of the residue gas and NGLs to the producer (take-in-kind arrangements) and sells the volumes MPLX retains to third parties or related parties. Revenue is recognized on a net basis when MPLX acts as an agent and does not have control of the gross amount of gas and/or NGLs prior to it being sold. Percent-of-proceeds revenue is reported as Service revenue - product related on the Consolidated Statements of Income.
•Keep-whole arrangements – Under keep-whole arrangements, MPLX gathers natural gas from the producer, processes the natural gas and sells the resulting condensate and NGLs to third parties at market prices. Because the extraction of the condensate and NGLs from the natural gas during processing reduces the Btu content of the natural gas, MPLX must either purchase natural gas at market prices for return to producers or make cash payment to the producers equal to the value of the energy content of this natural gas. Certain keep-whole arrangements also have provisions that require MPLX to share a percentage of the keep-whole profits with the producers based on the oil to gas ratio or the NGL to gas ratio. Service revenue - product related is recorded based on the value of the NGLs received on the date the services are performed. Natural gas purchased to return to the producer and shared NGL profits are recorded as a reduction of Service revenue - product related on the Consolidated Statements of Income on the date the services are performed. Sales of NGLs under these arrangements are reported as Product sales on the Consolidated Statements of Income and are reported on a gross basis as MPLX is the principal in the arrangement and controls the product prior to sale. The sale of the NGLs may occur shortly after services are performed at the tailgate of the plant, or after a period of time as determined by MPLX.
•Purchase arrangements – Under purchase arrangements, MPLX purchases natural gas at either the wellhead or the tailgate of a plant. MPLX then gathers and delivers the natural gas to pipelines where MPLX may resell the natural gas. Wellhead purchase arrangements represent an arrangement with a supplier and are recorded in Purchased product costs. Often, MPLX earns fees for services performed prior to taking control of the product in these arrangements and Service revenue is recorded for these fees. Revenue generated from the sale of product obtained in tailgate purchase arrangements is reported as Product sales on the Consolidated Statements of Income and is recognized on a gross basis as MPLX purchases and takes control of the product prior to sale and is the principal in the transaction.
In many cases, MPLX provides services under contracts that contain a combination of more than one of the arrangements described above. When fees are charged (in addition to product received) under percent-of-proceeds arrangements, keep-whole arrangements or purchase arrangements, MPLX records such fees as Service revenue on the Consolidated Statements of Income. The terms of MPLX’s contracts vary based on gas quality conditions, the competitive environment when the contracts are signed, and customer requirements. Performance obligations are determined based on the specific terms of the arrangements, economics of the geographical regions, and the services offered and whether they are deemed distinct. MPLX allocates the consideration earned between the performance obligations based on the stand-alone selling price when multiple performance obligations are identified.
Revenue from MPLX’s service arrangements will generally be recognized over time as the performance obligation is satisfied as services are provided. MPLX has elected to use the output measure of progress to recognize revenue based on the units delivered, processed or transported. The transaction price may have fixed components related to minimum volume commitments and variable components, which are primarily dependent on volumes. Variable consideration will generally not be estimated at contract inception as the transaction price is specifically allocable to the services provided each period. In instances in which tiered pricing structures do not reflect our efforts to perform, MPLX will estimate variable consideration at contract inception. Product sales will be recognized at a point in time when control of the product transfers to the customer.
Minimum volume commitments may create contract liabilities if current period payments can be used for future services. If a customer fails to meet its minimum committed volumes, it owes MPLX a deficiency payment based on the terms of the applicable agreement. The deficiency amounts received under these agreements (excluding payments received under agreements classified as sales-type leases) are recorded as Current liabilities or Current liabilities - related parties. In many cases, the customer may then apply the amount of any such deficiency payments as a credit for volumes in excess of its minimum volume commitment in future periods under the terms of the applicable agreements. MPLX recognizes revenue for the deficiency payments when credits are used for volumes in excess of minimum quarterly volume commitments, where it is probable the customer will not use the credit in future periods or upon the expiration of the credits. The use or expiration of the credits is a decrease in Current liabilities or Current liabilities - related parties. Deficiency payments under agreements that have been classified as sales-type leases are recorded as a reduction against the corresponding lease receivable.
Amounts billed to customers for shipping and handling, electricity, and other costs to perform services are included in the transaction price as a component of Revenues and other income on the Consolidated Statements of Income. Shipping and handling costs associated with product sales are included in Purchased product costs on the Consolidated Statements of Income.
Customers usually pay monthly based on the products purchased or services performed that month. Taxes collected from customers and remitted to the appropriate taxing authority are excluded from revenue.
Based on the terms of certain contracts, MPLX is considered to be the lessor under several implicit operating and sales-type lease arrangements in accordance with GAAP. Revenue and costs related to the portion of the revenue earned under these contracts considered to be implicit operating leases are recorded as Rental income and Rental cost of sales, respectively, on the Consolidated Statements of Income. Revenue related to the portion of the revenue earned under these contracts considered to
be implicit sales-type lease arrangements is recorded as Sales-type lease revenue on the Consolidated Statements of Income, while related costs are recorded to Cost of revenues or Purchases - related parties.
Revenue and expense accruals
Revenue and Expense Accruals
MPLX routinely makes accruals based on estimates for both revenues and expenses due to the timing of compiling billing information, receiving certain third-party information and reconciling MPLX’s records with those of third parties. The delayed information from third parties includes, among other things, actual volumes purchased, transported or sold, adjustments to inventory and invoices for purchases, actual natural gas and NGL deliveries, and other operating expenses. MPLX makes accruals to reflect estimates for these items based on its internal records and information from third parties. Estimated accruals are adjusted when actual information is received from third parties and MPLX’s internal records have been reconciled.
Other taxes
Other Taxes
Other taxes primarily include real estate taxes.
Cash and Cash Equivalents
Cash and Cash Equivalents
Cash and cash equivalents include cash on hand and on deposit and investments in highly liquid debt instruments with original maturities of three months or less.
Receivables
Receivables
Our receivables primarily consist of customer accounts receivable, which are recorded at the invoiced amounts and generally do not bear interest. Allowances for expected credit losses are estimated upon initial recognition of the receivables and updated each reporting period based on historical loss experience, current conditions and reasonable and supportable forecasts of future economic conditions. The allowance represents management’s best estimate of expected credit losses over the life of the receivables. We review the allowance quarterly and adjust as necessary for changes in risk factors and economic conditions. Past-due balances over 150 days are reviewed individually for collectability. Receivables deemed uncollectible are written off against the allowance, and recoveries are recognized when received.
Lessee, Leases
Leases
Contracts with a term greater than one year that convey the right to direct the use of and obtain substantially all of the economic benefit of an asset are accounted for as right of use (“ROU”) assets and lease liabilities.
ROU asset and lease liability balances are recorded at the commencement date at present value of the fixed lease payments using a secured incremental borrowing rate with a maturity similar to the lease term because our leases do not provide implicit rates. We have elected to include both lease and non-lease components in the present value of the lease payments for all lessee asset classes with the exception of our marine and third-party contractor service and equipment leases. The lease component of the payment for the marine and equipment asset classes is determined using a relative standalone selling price. Operating lease expense is recognized on a straight-line basis over the lease term. See Note 21 for additional disclosures about our lease contracts.
Lessor, Leases As a lessor under ASC 842, MPLX may be required to re-classify existing operating leases to sales-type leases upon modification and related reassessment of the leases. See Note 21 for further information regarding our ongoing evaluation of the impacts of lease reassessments as modifications occur. The net investment in sales-type leases with third parties is recorded within Receivables, less allowance for expected credit loss and Other noncurrent assets on the Consolidated Balance Sheets. The net investment in sales-type leases with related parties is recorded within Current assets - related parties and Noncurrent assets - related parties on the Consolidated Balance Sheets. These amounts are comprised of the present value of the sum of the future minimum lease payments representing the value of the lease receivable and the unguaranteed residual value of the leased assets. Management assesses the net investment in sales-type leases for recoverability quarterly.
Inventories
Inventories
Inventories consist of materials and supplies to be used in operations, line fill and other NGLs. Cost for materials and supplies are determined primarily using the weighted-average cost method. Inventories are valued at the lower of cost or net realizable value.
Imbalances
Imbalances
Within our pipelines and storage assets, we experience volume gains and losses due to pressure and temperature changes, evaporation and variances in meter readings and other measurement methods. Until settled, positive imbalances are recorded as other current assets and negative imbalances are recorded as accounts payable. Positive and negative imbalances are settled in cash, settled by physical delivery of volumes from a different source, or tracked and settled in the future.
Investment in unconsolidated affiliates
Investment in Unconsolidated Affiliates
Equity investments in which MPLX exercises significant influence but does not control and is not the primary beneficiary, are accounted for using the equity method and are reported in Equity method investments on the accompanying Consolidated
Balance Sheets. This includes entities in which we hold majority ownership, but the minority shareholders have substantive participating rights. Differences in the basis of the investments and the separate net asset values of the investees, if any, are amortized into net income over the remaining useful lives of the underlying assets and liabilities, except for the excess related to goodwill.
Regular evaluation of these investments is appropriate to evaluate any potential need for impairment. MPLX uses evidence of a loss in value to identify if an investment has an other than a temporary decline. Impairments are recorded through Income from equity method investments.
Property, plant and equipment
Property, Plant and Equipment
Property, plant and equipment are recorded at cost and depreciated on a straight-line basis over the estimated useful lives of the assets. Expenditures that extend the useful lives of assets are capitalized.
Long-lived assets used in operations are assessed for impairment whenever changes in facts and circumstances indicate that the carrying value of the assets may not be recoverable based on the expected undiscounted future cash flows of an asset group. For purposes of impairment evaluation, long-lived assets must be grouped at the lowest level for which independent cash flows can be identified, which is at least at the reporting unit level and in some cases for similar assets in the same geographic region where cash flows can be separately identified. If the sum of the undiscounted future cash flows from the use of the asset group and its eventual disposition is less than the carrying value of an asset group, an impairment assessment is performed and the excess of the book value over the fair value is recorded as an impairment loss.
When items of property, plant and equipment are sold or otherwise disposed of, any gains or losses are reported on the Consolidated Statements of Income. Gains on the disposal of property, plant and equipment are recognized when earned, which is generally at the time of closing. If a loss on disposal is expected, such losses are recognized when the assets are classified as held for sale.
Interest costs for the construction or development of long-lived assets are capitalized and amortized over the related asset’s estimated useful life.
Goodwill and Intangibles
Goodwill and Intangibles
Goodwill represents the excess of the purchase price over the estimated fair value of the net assets acquired in the acquisition of a business. Goodwill is not amortized, but rather is tested for impairment at the reporting unit level annually and when events or changes in circumstances indicate that the fair value of a reporting unit with goodwill has been reduced below carrying value. If we determine, based on a qualitative assessment, that it is more likely than not that a reporting unit’s fair value exceeds its carrying amount, no further impairment testing is required. If we do not perform a qualitative assessment or if that assessment indicates that further impairment testing is required, the fair value of each reporting unit is determined using an income and market approach which is compared to the carrying value of the reporting unit. If the carrying amount of the reporting unit exceeds its fair value, an impairment loss would be recognized in an amount equal to that excess, limited to the total amount of goodwill allocated to that reporting unit. The fair value under the income approach is calculated using the expected present value
of future cash flows method. Significant assumptions used in the cash flow forecasts include future volumes, discount rates, and future capital requirements. See Note 14 for further details.
Amortization of intangibles with definite lives is calculated using the straight-line method, which is reflective of the benefit pattern in which the estimated economic benefit is expected to be received over the estimated useful life of the intangible asset. Intangibles subject to amortization are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of the intangible may not be recoverable. If the sum of the expected undiscounted future cash flows related to the asset is less than the carrying amount of the asset, an impairment loss is recognized based on the fair value of the asset.
Environmental costs
Environmental Costs
Environmental expenditures for additional equipment that mitigates or prevents future contamination or improves environmental safety or efficiency of the existing assets are capitalized. We recognize remediation costs and penalties when the responsibility to remediate is probable and the amount of associated costs can be reasonably estimated. The timing of remediation accruals coincides with the completion of a feasibility study or the commitment to a formal plan of action. Remediation liabilities are accrued based on estimates of known environmental exposure and are discounted when the estimated amounts are reasonably fixed and determinable. If recoveries of remediation costs from third parties are probable, a receivable is recorded and is discounted when the estimated amount is reasonably fixed and determinable.
Asset retirement obligations
Asset Retirement Obligations
An ARO is a legal obligation associated with the retirement of tangible long-lived assets that generally result from the acquisition, construction, development or normal operation of the asset. The fair value of AROs is recognized in the period in which the obligations are incurred, if a reasonable estimate of fair value can be made, and added to the carrying amount of the associated asset. This additional carrying amount is then depreciated over the life of the asset. The liability is determined using a credit adjusted risk free interest rate and increases due to the passage of time based on the time value of money until the obligation is settled. AROs have not been recognized for certain assets because the fair value cannot be reasonably estimated since the settlement dates of the obligations are indeterminate. Such obligations will be recognized in the period when sufficient information becomes available to estimate a range of potential settlement dates. As of December 31, 2025 and 2024, MPLX’s asset retirement obligation was $45 million and $41 million, respectively, and is included on the balance sheet within Other long-term liabilities.
Derivative instruments
Derivative Instruments
MPLX may use commodity derivatives to economically hedge a portion of its exposure to commodity price risk. All derivative instruments (including derivatives embedded in other contracts) are recorded at fair value. MPLX discloses the fair value of all derivative instruments under the captions Other current assets, Other noncurrent assets, Other current liabilities and Other long-term liabilities on the Consolidated Balance Sheets. Certain commodity derivative positions may be governed by master netting arrangements and reflected on the consolidated balance sheets on a net basis by counterparty. MPLX did not utilize any commodity derivatives during the years ended December 31, 2025 or 2024. We make a distinction between realized or unrealized gains and losses on derivatives. During the period when a derivative contract is outstanding, changes in the fair value of the derivative are recorded as an unrealized gain or loss. When a derivative contract matures or is settled, the previously recorded unrealized gain or loss is reversed, and the realized gain or loss of the contract is recorded. Changes in the fair value of derivative instruments are reported on the Consolidated Statements of Income in accounts related to the item whose value or cash flows are being managed. Derivative instruments are marked to market through Product sales and Purchased product costs on the Consolidated Statements of Income.
During the years ended December 31, 2025, 2024 and 2023, MPLX did not elect hedge accounting for any derivatives. MPLX has historically elected the normal purchases and normal sales designation for certain contracts related to the physical purchase of electric power and the sale of most commodities.
Fair value measurement
Fair Value Measurement
Financial assets and liabilities recorded at fair value in the Consolidated Balance Sheets are categorized based upon the fair value hierarchy established by GAAP, which classifies the inputs used to measure fair value into Level 1, Level 2 or Level 3. A financial instrument’s categorization within the valuation hierarchy is based upon the lowest level of input that is significant to the fair value measurement. The methods and assumptions utilized may produce a fair value that may not be realized in future periods upon settlement. Furthermore, while MPLX believes its valuation methods are appropriate and consistent with other market participants, the use of different methodologies or assumptions to determine the fair value of certain financial instruments could result in a different estimate of fair value at the reporting date. For further discussion, see Note 15.
Equity-based compensation arrangements
Equity-Based Compensation Arrangements
MPLX issues phantom units under the MPLX LP 2018 Incentive Compensation Plan. A phantom unit entitles the grantee a right to receive a common unit upon the issuance of the phantom unit. The fair value of phantom unit awards granted to employees and non-management directors is based on the fair market value of MPLX LP common units on the date of grant. The fair value of the units awarded is amortized into earnings using a straight-line amortization schedule over the period of service
corresponding with the vesting period. For phantom units that vest immediately and are not forfeitable, equity-based compensation expense is recognized at the time of grant.
To satisfy common unit awards, MPLX may issue new common units, acquire common units in the open market or use common units already owned by the general partner.
Income Tax
Income Taxes
MPLX is not a taxable entity for United States federal income tax purposes or for the majority of the states that impose an income tax. Taxes on MPLX’s net income generally are borne by its partners through the allocation of taxable income. MPLX’s taxable income or loss, which may vary substantially from the net income or loss reported on the Consolidated Statements of Income, is includable in the federal income tax returns of each partner. MPLX and certain legal entities are, however, taxable entities under certain state jurisdictions.
MPLX accounts for income taxes under the asset and liability method. Deferred income taxes are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax basis, capital loss carryforwards and net operating loss and credit carryforwards. Deferred tax assets and liabilities are measured using enacted tax rates applied to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect of any tax rate change on deferred taxes is recognized as tax expense/(benefit) from continuing operations in the period that includes the enactment date of the tax rate change. Realizability of deferred tax assets is assessed and, if not more likely than not, a valuation allowance is recorded to reflect the deferred tax assets at net realizable value as determined by management. All deferred tax balances are classified as long-term in the accompanying Consolidated Balance Sheets. All changes in the tax bases of assets and liabilities are allocated among operations and items charged or credited directly to equity.
Distributions
Distributions
In preparing the Consolidated Statements of Equity, net income attributable to MPLX LP is allocated to preferred unitholders based on a fixed distribution schedule, as discussed in Notes 7 and 9, and subsequently allocated to the limited partner unitholders. Distributions are not accrued until declared. The allocation of net income attributable to MPLX LP for purposes of calculating net income per limited partner unit is described below.
Net income per limited partner unit
Net Income Per Limited Partner Unit
MPLX uses the two-class method when calculating the net income per unit applicable to limited partners, because there is more than one class of participating security. The classes of participating securities include common units, preferred units and certain equity-based compensation awards.
Net income attributable to MPLX LP is allocated to the unitholders differently for preparation of the Consolidated Statements of Equity and the calculation of net income per limited partner unit. In preparing the Consolidated Statements of Equity, net income attributable to MPLX LP is allocated to preferred unitholders based on a fixed distribution schedule and subsequently allocated to remaining unitholders in accordance with their respective ownership percentages. The allocation of net income attributable to MPLX LP for purposes of calculating net income per limited partner unit is described in Note 8.
In preparing net income per limited partner units, during periods in which a net loss attributable to MPLX is reported or periods in which the total distributions exceed the reported net income attributable to MPLX’s unitholders, the amount allocable to certain equity-based compensation awards is based on actual distributions to the equity-based compensation awards. Diluted earnings per unit is calculated by dividing net income attributable to MPLX’s common unitholders, after deducting amounts allocable to other participating securities, by the weighted average number of common units and potential common units outstanding during the period. Potential common units are excluded from the calculation of diluted earnings per unit during periods in which net income attributable to MPLX’s unitholders, after deducting amounts that are allocable to the outstanding equity-based compensation awards and preferred units, is a loss, as the impact would be anti-dilutive.
Business combinations
Business Combinations
We recognize and measure the assets acquired and liabilities assumed in a business combination based on their estimated fair values at the acquisition date. Any excess or deficit of the purchase consideration when compared to the fair value of the net tangible assets acquired, if any, is recorded as goodwill or gain from a bargain purchase. Depending on the nature of the transaction, management may engage an independent valuation specialist to assist with the determination of fair value of the assets acquired, liabilities assumed, noncontrolling interests, if any, and goodwill, based on recognized business valuation methodologies. An income, market or cost valuation method may be utilized to estimate the fair value of the assets acquired, liabilities assumed, and noncontrolling interests, if any, in a business combination. The income valuation method represents the present value of future cash flows over the life of the asset using: (i) discrete financial forecasts, which rely on management’s estimates of volumes, certain commodity prices, revenue and operating expenses; (ii) long-term growth rates; and (iii) appropriate discount rates. The market valuation method uses prices paid for a reasonably similar asset by other purchasers in the market, with adjustments relating to any differences between the assets. The cost valuation method is based on the replacement cost of a comparable asset at prices at the time of the acquisition reduced for depreciation of the asset. If the initial accounting for the business combination is incomplete by the end of the reporting period in which the acquisition occurs, an
estimate will be recorded. Subsequent to the acquisition, and not later than one year from the acquisition date, MPLX will record any material adjustments to the initial estimate based on new information obtained that would have existed as of the acquisition date. Any adjustment that arises from information obtained that did not exist as of the date of the acquisition will be recorded in the period of the adjustment. Acquisition-related costs are expensed as incurred in connection with each business combination.
Acquisitions in which the company or business being acquired by MPLX had an existing relationship with MPC may result in the transaction being considered a transfer between entities under common control. In these situations, MPLX records the assets acquired and liabilities assumed on its consolidated balance sheets at MPC’s historical carrying value. For the acquiring entity, transfers of businesses between entities under common control require prior periods to be retrospectively adjusted for those dates that the entity was under common control.
Consolidation, Variable Interest Entity, Policy
Variable Interest Entities
We evaluate all legal entities in which we hold an ownership or other pecuniary interest to determine if the entity is a VIE. Our interests in a VIE are referred to as variable interests. Variable interests can be contractual, ownership or other pecuniary interests in an entity that change with changes in the fair value of the VIE’s assets. When we conclude that we hold an interest in a VIE, we must determine if we are the entity’s primary beneficiary. A primary beneficiary is deemed to have a controlling financial interest in a VIE. This controlling financial interest is evidenced by both (i) the power to direct the activities of the VIE that most significantly impact the VIE’s economic performance and (ii) the obligation to absorb losses that could potentially be significant to the VIE or the right to receive benefits that could potentially be significant to the VIE. We consolidate any VIE when we determine that we are the primary beneficiary. We must disclose the nature of any interests in a VIE that is not consolidated.
Significant judgment is exercised in determining that a legal entity is a VIE and in evaluating our interest in a VIE. We use primarily a qualitative analysis to determine if an entity is a VIE. We evaluate the entity’s need for continuing financial support; the equity holder’s lack of a controlling financial interest; and/or if an equity holder’s voting interests are disproportionate to its obligation to absorb expected losses or receive residual returns. We evaluate our interests in a VIE to determine whether we are the primary beneficiary. We use a primarily qualitative analysis to determine if we are deemed to have a controlling financial interest in the VIE, either on a standalone basis or as part of a related party group. We continually monitor our interests in legal entities for changes in the design or activities of an entity and changes in our interests, including our status as the primary beneficiary to determine if the changes require us to revise our previous conclusions.
Changes in the design or nature of the activities of a VIE, or our involvement with a VIE, may require us to reconsider our conclusions on the entity’s status as a VIE and/or our status as the primary beneficiary. Such reconsideration requires significant judgment and understanding of the organization. This could result in the deconsolidation or consolidation of the affected subsidiary, which would have a significant impact on our financial statements.
See Note 5 for additional disclosures about our VIEs.
v3.25.4
Acquisitions and Other Transactions (Tables)
 12 Months Ended
Dec. 31, 2025
Northwind Midstream  
Business Combination [Line Items]  
Business Combination, Recognized Asset Acquired and Liability Assumed
The following table reflects our preliminary allocation of the $2.4 billion purchase price of the Northwind Midstream assets and liabilities, as well as measurement period adjustments since the acquisition date:
(In millions)August 29,
2025		AdjustmentsDecember 31,
2025
Assets acquired:
Cash and cash equivalents$17 $— $17 
Receivables11 — 11 
Other current assets1 — 1 
Property, plant and equipment1,182 (13)1,169 
Intangibles951 — 951 
Other noncurrent assets2 — 2 
Total assets acquired2,164 (13)2,151 
Liabilities assumed:
Accounts payable15 7 22 
Accrued property, plant and equipment84 — 84 
Accrued liabilities6 3 9 
Other current liabilities1 — 1 
Long-term operating lease liabilities1 — 1 
Total liabilities assumed107 10 117 
Total identifiable net assets2,057 (23)2,034 
Goodwill356 23 379 
Fair value of net assets acquired$2,413 $— $2,413 
BANGL, LLC  
Business Combination [Line Items]  
Business Combination, Recognized Asset Acquired and Liability Assumed The following table reflects our preliminary determination of the fair value of the BANGL assets and liabilities:
(In millions)July 1,
2025
Assets acquired:
Cash and cash equivalents$18 
Other current assets4 
Property, plant and equipment1,550 
Intangibles77 
Other noncurrent assets22 
Total assets acquired1,671 
Liabilities assumed:
Long-term debt due within one year46 
Other current liabilities42 
Long-term debt610 
Other long-term liabilities1 
Total liabilities assumed699 
Total identifiable net assets972 
Goodwill731 
Fair value of net assets acquired$1,703 
Schedule of Business Combination, Consideration
The following table summarizes the purchase price consideration in connection with the BANGL Acquisition:
Total cash paid$703 
Fair value of contingent consideration as of acquisition date234 
Total consideration937 
Fair value of previously held equity interest766 
Fair value of net assets acquired$1,703 
MarkWest Tornado GP, L.L.C.  
Business Combination [Line Items]  
Business Combination, Recognized Asset Acquired and Liability Assumed The following table reflects our determination of the fair value of the Torñado assets and liabilities (in millions):
(In millions)
Property, Plant and Equipment$585 
Intangibles75 
Working capital, net 30 
Other Long-term assets and liabilities, net(17)
Total net assets and liabilities$673 
v3.25.4
Investments and Noncontrolling Interests (Tables)
 12 Months Ended
Dec. 31, 2025
Equity Method Investments and Joint Ventures [Abstract]  
Equity Method Investments
The following table presents MPLX’s equity method investments at the dates indicated:
Ownership as ofCarrying value at
December 31,December 31,
(In millions, except ownership percentages)VIE202520252024
Crude Oil and Products Logistics
Illinois Extension Pipeline Company, L.L.C.35%$208 $218 
LOOP LLC41%313 310 
MarEn Bakken Company LLC(1)
25%502 526 
Other(2)
X558 541 
Total Crude Oil and Products Logistics
1,581 1,595 
Natural Gas and NGL Services
BANGL, LLC(3)
— 281 
MarkWest EMG Jefferson Dry Gas Gathering Company, L.L.C.(4)
X67%407 329 
MarkWest Utica EMG, L.L.C.X61%890 742 
Ohio Gathering Company L.L.C.(5)
X32%444 470 
Sherwood Midstream LLCX50%475 488 
Texas City Logistics LLCX50%163 — 
WPC Parent, LLC30%273 208 
Other(2)
X565 418 
Total Natural Gas and NGL Services
3,217 2,936 
Total$4,798 $4,531 
(1)    The investment in MarEn Bakken Company LLC includes our 9.19 percent indirect interest in a joint venture (“Dakota Access”) that owns and operates the Dakota Access Pipeline and Energy Transfer Crude Oil Pipeline projects (collectively, the “Bakken Pipeline system”).
(2)    Included within Other are certain equity method investments that have been deemed to be VIEs. The December 31, 2024 Natural Gas and NGL Services value includes $129 million in investments associated with the Rockies, which were divested in the fourth quarter 2025.
(3)    At December 31, 2024, we owned a 45 percent interest in BANGL. On July 1, 2025, we acquired the remaining 55 percent interest in BANGL. As a result of acquiring the remaining interest, we obtained control and now consolidate BANGL.
(4)    On March 31, 2025, MPLX contributed a wholly-owned subsidiary with a fair value of $125 million to MarkWest EMG Jefferson Dry Gas Gathering Company, L.L.C. As a result of the transaction, MPLX received special distributions of $42 million in 2025, which are reflected as a return of capital on the Consolidated Statement of Cash Flows.
(5)    MPLX also holds a 41 percent indirect interest in OGC through our ownership interest in MarkWest Utica EMG, L.L.C.
Investment Company, Nonconsolidated Subsidiary, Summarized Financial Information
Summarized financial information for MPLX’s equity method investments is as follows:
(In millions)202520242023
Income statement data:
Revenues and other income$3,959 $3,594 $3,262 
Costs and expenses1,579 1,535 1,331 
Income from operations2,380 2,059 1,930 
Net income1,854 1,631 1,634 
Balance sheet data:
Current assets1,347 1,570 1,531 
Noncurrent assets 20,199 17,927 13,860 
Current liabilities1,044 746 979 
Noncurrent liabilities 7,011 6,711 4,856 
v3.25.4
Related Party Agreements and Transactions (Tables)
 12 Months Ended
Dec. 31, 2025
Related Party Transactions [Abstract]  
Schedule of Short-Term Debt [Table Text Block]
Activity on the MPC Loan Agreement for the year ended December 31, 2025 is summarized in the table below. There was no activity on the MPC Loan Agreement for the years ended December 31, 2024 and 2023.
(In millions, except %)2025
Borrowings$50 
Weighted average interest rate of borrowings5.68 %
Repayments$50 
Outstanding balance at end of period$— 
Schedule of Related Party Transactions [Table Text Block]
Assets and liabilities with related parties appearing in the Consolidated Balance Sheets are detailed in the table below. This table identifies the various components of related party assets and liabilities, including those associated with leases (see Note 21 for additional information) and deferred revenue.
December 31,
(In millions)20252024
Current assets - related parties
Receivables$624 $620 
Lease receivables269 204 
Prepaid5 5 
Other1 1 
Total899 830 
Noncurrent assets - related parties
Long-term lease receivables421 677 
Right of use assets239 226 
Unguaranteed residual asset263 189 
Long-term receivables39 28 
Total962 1,120 
Current liabilities - related parties
MPC loan agreement and other payables(1)
290 288 
Deferred revenue107 106 
Operating lease liabilities2 2 
Total399 396 
Long-term liabilities - related parties
Long-term operating lease liabilities237 224 
Long-term deferred revenue127 110 
Total$364 $334 
(1)    There were no borrowings outstanding on the MPC Loan Agreement as of December 31, 2025 or December 31, 2024.
v3.25.4
Equity (Tables)
 12 Months Ended
Dec. 31, 2025
Equity [Abstract]  
Schedule of Stockholders Equity [Table Text Block] The changes in the number of common units during the years ended December 31, 2023, 2024 and 2025 are summarized below:
(In units)Common Units
Balance at December 31, 20221,001,020,616 
Unit-based compensation awards196,428 
Conversion of Series A preferred units2,281,831 
Balance at December 31, 20231,003,498,875 
Unit-based compensation awards141,985 
Conversion of Series A preferred units(1)
21,078,998 
Units redeemed in unit repurchase program(7,577,568)
Balance at December 31, 20241,017,142,290 
Unit-based compensation awards147,670 
Conversion of Series A preferred units(1)
6,166,965 
Units redeemed in unit repurchase program(7,754,885)
Balance at December 31, 20251,015,702,040 
(1)    Certain Series A preferred unitholders have exercised their rights to convert their Series A preferred units into common units as discussed in Note 9.
Class of Treasury Stock [Table Text Block]
Total unit repurchases were as follows for the years ended December 31, 2025, 2024 and 2023:
(In millions, except per unit data)202520242023
Number of common units repurchased8 8 — 
Cash paid for common units repurchased(1)
$400 $326 $— 
Average cost per unit(1)
$51.58 $43.04 $— 
(1)Cash paid for common units repurchased and average cost per unit includes commissions paid to brokers during the period.
Dividends Declared
Total distributions declared for the years ended December 31, 2025, 2024 and 2023 are summarized in the table below.
202520242023
Distributions per common unit$4.066 $3.613 $3.250 
Distributions Made to Limited Partner, by Distribution [Table Text Block]
The allocation of total quarterly cash distributions to common and preferred unitholders is as follows for the years ended December 31, 2025, 2024 and 2023. The Sixth Amended and Restated Agreement of Limited Partnership, dated as of February 1, 2021 (“Partnership Agreement”) sets forth the calculation to be used to determine the amount and priority of cash distributions that the common unitholders and preferred unitholders will receive. MPLX’s distributions are declared for the prior quarter subsequent to the quarter end; therefore, the following table represents total cash distributions applicable to the period for which the distributions relate as opposed to the quarter in which they were declared and paid.
(In millions)202520242023
Common and preferred unit distributions:
Common unitholders, includes common units of general partner$4,138 $3,678 $3,256 
Series A preferred unit distributions— 27 94 
Series B preferred unit distributions(1)
— — 5 
Total cash distributions declared$4,138 $3,705 $3,355 
(1)    2023 period includes the portion of the $21 million distribution paid to the Series B preferred unitholders on February 15, 2023 that was earned during the period prior to the redemption.
v3.25.4
Net Income (Loss) Per Limited Partner Unit (Tables)
 12 Months Ended
Dec. 31, 2025
Earnings Per Share [Abstract]  
Schedule of Net Income Per Unit, Basic and Diluted [Table Text Block]
(In millions, except per unit data)202520242023
Net income attributable to MPLX LP(1):
$4,912 $4,317 $3,928 
Less: Distributions declared on Series A preferred units— 27 94 
Distributions declared on Series B preferred units— — 5 
Distributed and undistributed earnings allocated to other participating securities
3 9 16 
Impact of redemption of Series B preferred units— — 5 
Net Income available to common unitholders$4,909 $4,281 $3,808 
Weighted average units outstanding:
Basic1,019 1,016 1,001 
Diluted1,019 1,017 1,002 
Net income attributable to MPLX LP per limited partner unit:
Basic$4.82 $4.21 $3.80 
Diluted$4.82 $4.21 $3.80 
(1)    Allocation of net income attributable to MPLX LP assumes all earnings for the period have been distributed based on the distribution priorities applicable to the period.
 [1]
[1] Allocation of net income attributable to MPLX LP assumes all earnings for the period have been distributed based on the distribution priorities applicable to the period.
v3.25.4
Segment Information (Tables)
 12 Months Ended
Dec. 31, 2025
Segment Reporting [Abstract]  
Schedule of Segment Reporting Information, by Segment [Table Text Block]
The tables below present information about our reportable segments:
(In millions)202520242023
Crude Oil and Products Logistics
Service revenue$4,824 $4,543 $4,335 
Rental income923 882 857 
Product related revenue16 18 18 
Sales-type lease revenue448 475 500 
Income from equity method investments243 269 270 
Other income121 152 68 
Total segment revenues and other income(1)
6,575 6,339 6,048 
Operating expenses2,173 2,097 2,006 
Other segment items(2)
(145)(133)(92)
Segment Adjusted EBITDA(3)
4,547 4,375 4,134 
Capital expenditures538 482 414 
Investments in unconsolidated affiliates(4)
— 93 8 
Natural Gas and NGL Services
Service revenue2,468 2,407 2,189 
Rental income226 222 208 
Product related revenue2,418 2,221 2,191 
Sales-type lease revenue151 136 136 
Income from equity method investments(5)
454 533 330 
Gain on equity method investments(6)
484 20 92 
Other income222 55 87 
Total segment revenues and other income(1)
6,423 5,594 5,233 
Purchased product costs1,815 1,561 1,598 
Operating expenses1,716 1,704 1,564 
Other segment items(2)
422 (60)(64)
Segment Adjusted EBITDA(3)
2,470 2,389 2,135 
Capital expenditures1,418 568 605 
Investments in unconsolidated affiliates(4)
$794 $143 $90 
(1)    Within the total segment revenues and other income amounts presented above, third-party revenues for the Crude Oil and Products Logistics segment were $751 million, $746 million and $701 million for the years ended December 31, 2025, 2024 and 2023, respectively. Third-party revenues for the Natural Gas and NGL Services segment were $6,210 million, $5,297 million and $4,902 million for the years ended December 31, 2025, 2024 and 2023, respectively.
(2)    Other segment items in the Crude Oil and Products Logistics segment include income from equity method investments, distributions and adjustments related to equity method investments, equity-based compensation and other miscellaneous items. Other segment items in the Natural Gas and NGL Services segment include income from and gain on equity method investments, distributions and adjustments related to equity method investments, gain on sale of assets, transaction-related costs, unrealized derivative gain/loss and other miscellaneous items.
(3)    See below for the reconciliation from Segment Adjusted EBITDA to Net income.
(4)    Investments in unconsolidated affiliates in the Crude Oil and Products Logistics segment includes a contribution of $92 million in 2024 to Dakota Access to fund our share of a debt repayment by the joint venture and excludes $18 million in 2024 related to acquisition of an additional interest in Wink to Webster Pipeline LLC. Investments in unconsolidated affiliates in the Natural Gas and NGL Services segment includes cash contributions to several joint ventures to fund current growth capital projects in 2025 and excludes $151 million in 2025 related to acquisition of an additional interest in the joint venture that owns and operates the Matterhorn Express Pipeline, a $49 million capital contribution in 2025 to WPC Parent, LLC to purchase Enbridge’s special membership interest in the Rio Bravo Pipeline project, a $13 million payment in 2025 related to earnout associated with MXP Parent, LLC, and $210 million in 2024 related to the acquisition of additional interests in BANGL, LLC.
(5)    Includes a $151 million gain related to the dilution of ownership interest in connection with the Whistler Joint Venture Transaction in 2024.
(6)    Gain on equity method investments represents the gain on remeasurement of our existing equity method investment in BANGL in conjunction with the BANGL Acquisition in 2025, the gain on remeasurement of our existing equity method investment in OCC in conjunction with the Utica Midstream Acquisition in 2024, and the gain on remeasurement of our existing equity method investment in Torñado in conjunction with the purchase of the remaining joint venture interest in 2023.
Reconciliation of Other Significant Reconciling Items from Segments to Consolidated [Table Text Block]
The table below provides a reconciliation of Segment Adjusted EBITDA for reportable segments to Net income.
(In millions)202520242023
Reconciliation to Net income:
Crude Oil and Products Logistics Segment Adjusted EBITDA
$4,547 $4,375 $4,134 
Natural Gas and NGL Services Segment Adjusted EBITDA
2,470 2,389 2,135 
Total reportable segments7,017 6,764 6,269 
Depreciation and amortization(1)
(1,351)(1,283)(1,213)
Net interest and other financial costs(983)(921)(923)
Income from equity method investments697 802 600 
Distributions/adjustments related to equity method investments(962)(928)(774)
Gain on equity method investments484 — 92 
Gain on sale of assets159 — — 
Transaction-related costs(2)
(33)— — 
Adjusted EBITDA attributable to noncontrolling interests44 44 42 
Garyville incident response costs(3)
— — (16)
Other(4)
(120)(121)(111)
Net income$4,952 $4,357 $3,966 
(1)    Depreciation and amortization attributable to Crude Oil and Products Logistics was $546 million, $526 million and $530 million for the years ended December 31, 2025, 2024 and 2023, respectively. Depreciation and amortization attributable to Natural Gas and NGL Services was $805 million, $757 million and $683 million for the years ended December 31, 2025, 2024 and 2023, respectively.
(2)    Transaction-related costs include costs associated with the Northwind Midstream Acquisition, the BANGL Acquisition and the divestiture of the Rockies gathering and processing operations discussed in Note 4.
(3)    In August 2023, a naphtha release and resulting fire occurred at our Garyville Tank Farm resulting in the loss of four storage tanks with a combined shell capacity of 894 thousand barrels. We incurred $16 million of incident response costs, net of insurance recoveries, during the year ended December 31, 2023.
(4)    Includes unrealized derivative gain/(loss), equity-based compensation, provision for income taxes and other miscellaneous items.
v3.25.4
Risks and Uncertainties (Tables)
 12 Months Ended
Dec. 31, 2025
Risks and Uncertainties [Abstract]  
Schedule of Revenue by Major Customers by Reporting Segments
The table below shows, by segment, the percentage of total revenues and other income with MPC, which is our most significant customer and our largest concentration of credit risk.
202520242023
Total revenues and other income(1)
Crude Oil and Products Logistics88 %88 %88 %
Natural Gas and NGL Services2 %4 %5 %
Total48 %49 %50 %
(1)    The percent calculations for the year ended December 31, 2025 exclude a $484 million gain on remeasurement of our existing equity method investment in BANGL in conjunction with the BANGL Acquisition and a $159 million gain on divestiture of the Rockies. The percent calculations for the year ended December 31, 2024 exclude a gain of $151 million related to the dilution of ownership interest in connection with the Whistler Joint Venture Transaction. The percent calculations for the year ended December 31, 2023 exclude a $92 million gain on remeasurement of our existing equity investment in Torñado. See Note 4 for additional information.
v3.25.4
Inventories (Tables)
 12 Months Ended
Dec. 31, 2025
Inventory Disclosure [Abstract]  
Summary of Inventories
Inventories consist of the following:
December 31,
(In millions)20252024
NGLs$5 $5 
Line fill2 18 
Spare parts, materials and supplies165 157 
Total inventories$172 $180 
v3.25.4
Property, Plant and Equipment (Tables)
 12 Months Ended
Dec. 31, 2025
Property, Plant and Equipment [Abstract]  
Summary of Property, Plant and Equipment
Property, plant and equipment with associated accumulated depreciation is shown below:
 Estimated
Useful Lives		December 31,
(In millions)20252024
Crude Oil and Products Logistics
Pipelines
15 - 50 years
$6,908 $6,627 
Refining logistics
15 - 20 years
1,990 1,867 
Terminals
15 - 40 years
1,869 1,726 
Marine
15 - 20 years
1,188 1,149 
Land, building and other
5 - 50 years
1,627 1,619 
Construction-in-progress227 201 
Total Crude Oil and Products Logistics property, plant and equipment
13,809 13,189 
Natural Gas and NGL Services
Gathering and transportation
5 - 40 years
9,379 7,789 
Treating, processing and fractionation
10 - 40 years
6,896 6,611 
Land, building and other
5 - 40 years
437 541 
Construction-in-progress1,238 274 
Total Natural Gas and NGL Services property, plant and equipment
17,950 15,215 
Total property, plant and equipment31,759 28,404 
Less accumulated depreciation10,061 9,250 
Property, plant and equipment, net$21,698 $19,154 
v3.25.4
Goodwill and Intangibles (Tables)
 12 Months Ended
Dec. 31, 2025
Goodwill and Intangible Assets Disclosure [Abstract]  
Schedule of Goodwill
The changes in carrying amount of goodwill were as follows for the periods presented:
(In millions)
Crude Oil and Products Logistics
Natural Gas and NGL ServicesTotal
Balance as of December 31, 2023$7,645 $— $7,645 
Impairment losses— — — 
Balance as of December 31, 20247,645 — 7,645 
Acquisitions(1)
— 1,110 1,110 
Impairment losses— — — 
Balance as of December 31, 20257,645 1,110 8,755 
Gross goodwill as of December 31, 20257,645 4,251 11,896 
Accumulated impairment losses— (3,141)(3,141)
Balance as of December 31, 2025$7,645 $1,110 $8,755 
(1)    Acquisitions in 2025 are inclusive of the Northwind Midstream Acquisition and the BANGL Acquisition.
Schedule of Acquired Finite-Lived Intangible Assets by Major Class
MPLX’s intangible assets are comprised of customer contracts and relationships. Gross intangible assets with accumulated amortization as of December 31, 2025 and 2024 is shown below:
December 31, 2025December 31, 2024
(In millions)Gross
Accumulated Amortization(1)
NetGross
Accumulated Amortization(1)
Net
Crude Oil and Products Logistics$308 $(260)$48 $283 $(224)$59 
Natural Gas and NGL Services2,175 (826)1,349 1,363 (904)459 
$2,483 $(1,086)$1,397 $1,646 $(1,128)$518 
(1)    Amortization expense attributable to the Crude Oil and Products Logistics segment for the years ended December 31, 2025 and 2024 was $36 million and $35 million, respectively. Amortization expense attributable to the Natural Gas and NGL Services segment for the years ended December 31, 2025 and 2024 was $105 million and $99 million, respectively.
Schedule of Finite-Lived Intangible Assets, Future Amortization Expense
Estimated future amortization expense related to the intangible assets at December 31, 2025 is as follows:
(In millions)
2026$164 
2027136 
2028125 
202991 
203091 
2031 and thereafter790 
Total$1,397 
v3.25.4
Fair Value Measurements (Tables)
 12 Months Ended
Dec. 31, 2025
Fair Value Disclosures [Abstract]  
Schedule of Derivative Instruments in Statement of Financial Position, Fair Value [Table Text Block]
The following table presents the impact on the Consolidated Balance Sheets of MPLX’s assets and liabilities measured at fair value on a recurring basis as of December 31, 2025 and 2024 by fair value hierarchy level.
December 31,
20252024
(In millions)Level 1Level 2Level 3Level 1Level 2Level 3
Liabilities:
Embedded derivatives in commodity contracts
Other current liabilities$— $— $6 $— $— $10 
Other long-term liabilities— — 35 — — 48 
Total embedded derivatives in commodity contracts— — 41 — — 58 
Contingent consideration / Other long-term liabilities— — 236 — — — 
Total carrying value in Consolidated Balance Sheets$— $— $277 $— $— $58 
Schedule of changes in Level 3 fair value measurements [Table Text Block]
The following table is a reconciliation of the net beginning and ending balances recorded for net liabilities classified as Level 3 in the fair value hierarchy.
(In millions)20252024
Beginning balance$(58)$(61)
Contingent consideration(1)
(234)— 
Unrealized and realized gain/(loss) included in Net income(2)
5 (10)
Settlements10 13 
Ending balance(277)(58)
The amount of total gain/(loss) for the period included in earnings attributable to the change in unrealized gain/(loss) relating to liabilities still held at end of period$7 $(7)
(1)    Liability recorded in the third quarter of 2025 related to the BANGL Acquisition earnout provision.
(2)    Gain/(loss) on derivatives embedded in commodity contracts are recorded in Purchased product costs in the Consolidated Statements of Income.
Schedule of Carrying Values and Estimated Fair Values of Debt Instruments The following table summarizes the fair value and carrying value of our third-party debt, excluding finance leases and unamortized debt issuance costs:
December 31,
20252024
(In millions)Fair ValueCarrying ValueFair ValueCarrying Value
Outstanding debt(1)
$24,887 $25,821 $19,574 $21,068 
(1)    Any amounts outstanding under the MPC Loan Agreement are not included in the table above, as the carrying value approximates fair value. This balance, if any, is reflected in Current liabilities - related parties in the Consolidated Balance Sheets.
v3.25.4
Derivative Financial Instruments (Tables)
 12 Months Ended
Dec. 31, 2025
Derivative Instruments and Hedging Activities Disclosure [Abstract]  
Derivative Instruments, Gain (Loss) [Table Text Block]
The impact of MPLX’s derivative contracts not designated as hedging instruments and the location of gains and losses recognized in the Consolidated Statements of Income is summarized below:
(In millions)202520242023
Product sales
Realized gain$— $1 $7 
Product sales derivative gain— 1 7 
Purchased product costs
Realized loss(10)(13)(11)
Unrealized gain17 3 — 
Purchased product cost derivative (loss)/gain7 (10)(11)
Total derivative (loss)/gain included in Net Income$7 $(9)$(4)
v3.25.4
Debt (Tables)
 12 Months Ended
Dec. 31, 2025
Debt Instrument [Line Items]  
Schedule of Debt [Table Text Block]
MPLX’s outstanding borrowings consist of the following:
 December 31,
(In millions)20252024
MPLX LP:
MPLX Credit Agreement$— $— 
4.000% senior notes due February 15, 2025
— 500 
4.875% senior notes due June 1, 2025
— 1,189 
1.750% senior notes due March 1, 2026
1,500 1,500 
4.125% senior notes due March 1, 2027
1,250 1,250 
4.250% senior notes due December 1, 2027
732 732 
4.000% senior notes due March 15, 2028
1,250 1,250 
4.800% senior notes due February 15, 2029
750 750 
2.650% senior notes due August 15, 2030
1,500 1,500 
4.800% senior notes due February 15, 2031
1,250 — 
4.950% senior notes due September 1, 2032
1,000 1,000 
5.000% senior notes due January 15, 2033
750 — 
5.000% senior notes due March 1, 2033
1,100 1,100 
5.500% senior notes due June 1, 2034
1,650 1,650 
5.400% senior notes due April 1, 2035
1,000 — 
5.400% senior notes due September 15, 2035
1,500 — 
4.500% senior notes due April 15, 2038
1,750 1,750 
5.200% senior notes due March 1, 2047
1,000 1,000 
5.200% senior notes due December 1, 2047
487 487 
4.700% senior notes due April 15, 2048
1,500 1,500 
5.500% senior notes due February 15, 2049
1,500 1,500 
4.950% senior notes due March 14, 2052
1,500 1,500 
5.650% senior notes due March 1, 2053
500 500 
5.950% senior notes due April 1, 2055
1,000 — 
6.200% senior notes due September 15, 2055
1,000 — 
4.900% senior notes due April 15, 2058
500 500 
Consolidated subsidiaries:
MarkWest - 4.875% senior notes, due 2025
— 11 
ANDX - 4.250% - 5.200% senior notes, due 2027-2047
31 31 
Finance lease obligations(1)
6 6 
Total26,006 21,206 
Unamortized debt issuance costs(174)(126)
Unamortized discount(179)(132)
Amounts due within one year(1,502)(1,693)
Total long-term debt due after one year$24,151 $19,255 
(1)    See Note 21 for lease information.
Schedule of Maturities of Long-Term Debt [Table Text Block]
The following table shows five years of scheduled debt payments, including payments on finance lease obligations, as of December 31, 2025:
(In millions) 
2026$1,503 
20272,002 
20281,250 
2029750 
20301,500 
Schedule of interest payable dates [Table Text Block]
Interest on each series of MPLX LP and ANDX senior notes outstanding is payable semi-annually in arrears, according to the table below.
Senior NotesInterest payable semi-annually in arrears
1.750% senior notes due March 1, 2026
March 1st and September 1st
4.125% senior notes due March 1, 2027
March 1st and September 1st
4.250% senior notes due December 1, 2027
June 1st and December 1st
4.000% senior notes due March 15, 2028
March 15th and September 15th
4.800% senior notes due February 15, 2029
February 15th and August 15th
2.650% senior notes due August 15, 2030
February 15th and August 15th
4.800% senior notes due February 15, 2031
February 15th and August 15th
4.950% senior notes due September 1, 2032
March 1st and September 1st
5.000% senior notes due January 15, 2033
January 15th and July 15th
5.000% senior notes due March 1, 2033
March 1st and September 1st
5.500% senior notes due June 1, 2034
June 1st and December 1st
5.400% senior notes due April 1, 2035
April 1st and October 1st
5.400% senior notes due September 15, 2035
March 15th and September 15th
4.500% senior notes due April 15, 2038
April 15th and October 15th
5.200% senior notes due March 1, 2047
March 1st and September 1st
5.200% senior notes due December 1, 2047
June 1st and December 1st
4.700% senior notes due April 15, 2048
April 15th and October 15th
5.500% senior notes due February 15, 2049
February 15th and August 15th
4.950% senior notes due March 14, 2052
March 14th and September 14th
5.650% senior notes due March 1, 2053
March 1st and September 1st
5.950% senior notes due April 1, 2055
April 1st and October 1st
6.200% senior notes due September 15, 2055
March 15th and September 15th
4.900% senior notes due April 15, 2058
April 15th and October 15th
Revolving Credit Facility  
Debt Instrument [Line Items]  
Schedule of Long-Term Debt Instruments
Activity on the MPLX Credit Agreement during the year ended December 31, 2025 is summarized in the table below. There were no revolver borrowings or repayments under the MPLX Credit Agreement during the year ended December 31, 2024.
(in millions, except %)2025
Borrowings$106 
Weighted average interest rate of borrowings7.74 %
Repayments$106 
Outstanding balance at end of period$— 
Letters of credit outstanding$0.2 
Total remaining availability on facility$2,000 
Percent of borrowing capacity available100 %
Senior Notes  
Debt Instrument [Line Items]  
Schedule of Long-Term Debt Instruments
The following table summarizes debt issuances during the year ended December 31, 2025, all of which were issued in an underwritten public offering:
Issue DateAggregate Principal Amount
(in millions)		NoteCoupon (percent)Price to Public
(percent of par)		Interest Payment DatesMaturity Date
March 10, 2025$1,000 
(1)
5.40099.398April 1 and October 1April 1, 2035
March 10, 20251,000 
(1)
5.95098.331April 1 and October 1April 1, 2055
August 11, 20251,250 
(2)
4.80099.880February 15 and August 15February 15, 2031
August 11, 2025750 
(2)
5.00098.936January 15 and July 15January 15, 2033
August 11, 20251,500 
(2)
5.40098.943March 15 and September 15September 15, 2035
August 11, 20251,000 
(2)
6.20098.277March 15 and September 15September 15, 2055
(1)    On April 9, 2025, MPLX used $1.2 billion of the net proceeds from the issuance of senior notes in March 2025 to redeem all of (i) MPLX’s outstanding $1,189 million aggregate principal amount of 4.875 percent senior notes due June 2025 and (ii) MarkWest’s outstanding $11 million aggregate principal amount of 4.875 percent senior notes due June 2025. The remaining net proceeds from this offering were used for general partnership purposes.
(2)    We used a portion of the net proceeds from this offering to fund the Northwind Midstream Acquisition, including the payment of related fees and expenses, and to increase cash and cash equivalents following the recently completed BANGL Acquisition and BANGL Debt Repayment. The remainder of the net proceeds from this offering were used for general partnership purposes.
v3.25.4
Net Interest and Other Financial Costs (Tables)
 12 Months Ended
Dec. 31, 2025
Other Income and Expenses [Abstract]  
Interest and Other Income
Net interest and other financial costs were as follows:
(In millions)202520242023
Interest expense$1,072 $963 $912 
Other financial costs21 72 69 
Interest income(68)(95)(43)
Capitalized interest(42)(19)(15)
Net interest and other financial costs$983 $921 $923 
v3.25.4
Revenue (Tables)
 12 Months Ended
Dec. 31, 2025
Revenue from Contract with Customer [Abstract]  
Disaggregation of Revenue [Table Text Block]
The following tables represent a disaggregation of revenue for each reportable segment for the years ended December 31, 2025, 2024 and 2023:
2025
(In millions)Crude Oil and Products LogisticsNatural Gas and NGL ServicesTotal
Revenues and other income:
Service revenue$453 $2,446 $2,899 
Service revenue - related parties4,371 22 4,393 
Service revenue - product related— 289 289 
Product sales4 1,998 2,002 
Product sales - related parties12 131 143 
Total revenues from contracts with customers$4,840 $4,886 9,726 
Non-ASC 606 revenue and other income(1)
3,272 
Total revenues and other income$12,998 
2024
(In millions)Crude Oil and Products LogisticsNatural Gas and NGL ServicesTotal
Revenues and other income:
Service revenue$391 $2,379 $2,770 
Service revenue - related parties4,152 28 4,180 
Service revenue - product related— 357 357 
Product sales5 1,652 1,657 
Product sales - related parties13 212 225 
Total revenues from contracts with customers$4,561 $4,628 9,189 
Non-ASC 606 revenue and other income(1)
2,744 
Total revenues and other income$11,933 
2023
(In millions)Crude Oil and Products LogisticsNatural Gas and NGL ServicesTotal
Revenues and other income:
Service revenue$369 $2,170 $2,539 
Service revenue - related parties3,966 19 3,985 
Service revenue - product related— 294 294 
Product sales5 1,660 1,665 
Product sales - related parties13 237 250 
Total revenues from contracts with customers$4,353 $4,380 8,733 
Non-ASC 606 revenue and other income(1)
2,548 
Total revenues and other income$11,281 
(1)    Non-ASC 606 Revenue and other income includes rental income, sales-type lease revenue, income from equity method investments and other income.
Contract with Customer, Contract Asset, Contract Liability, and Receivable [Table Text Block]
The tables below reflect the changes in ASC 606 contract balances for the years ended December 31, 2025 and 2024:
(In millions)Balance at December 31, 2024Additions/ (Deletions)
Revenue Recognized(2)
Balance at December 31, 2025
Contract assets$2 $13 $— $15 
Long-term contract assets— 4 — 4 
Deferred revenue84 9 (80)13 
Deferred revenue - related parties71 86 (91)66 
Long-term deferred revenue(1)
315 (198)— 117 
Long-term deferred revenue - related parties44 1 — 45 
(In millions)Balance at December 31, 2023Additions/ (Deletions)
Revenue Recognized(2)
Balance at December 31, 2024
Contract assets$3 $— $(1)$2 
Long-term contract assets1 (1)— — 
Deferred revenue59 86 (61)84 
Deferred revenue - related parties47 90 (66)71 
Long-term deferred revenue344 (29)— 315 
Long-term deferred revenue - related parties29 15 — 44 
(1)    Long-term deferred revenue deletions include $180 million removed in connection with the Rockies divestiture. See Note 4 for additional information related to the Rockies divestiture.
(2)    No significant revenue was recognized related to past performance obligations in the period presented.
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table Text Block]
The table below includes estimated revenue expected to be recognized in the future related to performance obligations that are unsatisfied (or partially unsatisfied) as of December 31, 2025. The amounts presented below are generally limited to fixed consideration from contracts with customers that contain minimum volume commitments.
A significant portion of our future contracted revenue is excluded from the amounts presented below in accordance with ASC 606. Variable consideration that is constrained or not required to be estimated as it reflects our efforts to perform is excluded from this disclosure. Additionally, we do not disclose information on the future performance obligations for any contract with an original expected duration of one year or less, or that are terminable by our customer with little or no termination penalties. Potential future performance obligations related to renewals that have not yet been exercised or are not certain of exercise are excluded from the amounts presented below. Revenues classified as Rental income and Sales-type lease revenue are also excluded from this table as they are disclosed in Note 21.
(In billions)
2026$2.0 
20271.9 
20280.7 
20290.3 
20300.2 
2031 and thereafter0.7 
Total revenue on remaining performance obligations$5.8 
As of December 31, 2025, unsatisfied performance obligations included in the Consolidated Balance Sheets are $241 million and will be recognized as revenue as the obligations are satisfied, which is generally expected to occur over the next 20 years. A portion of this amount is not disclosed in the table above as it is deemed variable consideration due to volume variability.
v3.25.4
Supplemental Cash Flow Information (Tables)
 12 Months Ended
Dec. 31, 2025
Supplemental Cash Flow Information [Abstract]  
Summary of Supplemental Cash Flow Information
(In millions)202520242023
Net cash provided by operating activities included:
Interest paid (net of amounts capitalized)$913 $940 $893 
Income taxes paid7 6 7 
Cash paid for amounts included in the measurement of lease liabilities:
Payments on operating leases64 71 71 
Net cash provided by financing activities included:
Principal payments under finance lease obligations2 1 1 
Non-cash investing and financing activities:
Net transfers of property, plant and equipment to materials and supplies inventories— — (8)
Contribution of assets(1)
115 — — 
ROU assets obtained in exchange for new operating lease obligations53 47 21 
ROU assets obtained in exchange for new finance lease obligations3 1 — 
Book value of equity method investment(2)
282 4 311 
Contingent consideration(3)
234 — — 
Other24 — — 
(1)    Represents the book value of assets contributed by MPLX to a joint venture.
(2)    Represents the book value of MPLX’s equity method investment in BANGL in 2025, OCC in 2024 and Torñado in 2023 prior to MPLX buying out the remaining interest in these entities. See Note 4 for additional information.
(3)    See Note 4 – BANGL, LLC Acquisitions.
Summary of Reconciliation of Additions to Property, Plant and Equipment to Total Capital Expenditures [Table Text Block]
The Consolidated Statements of Cash Flows exclude changes to the Consolidated Balance Sheets that did not affect cash. The following is a reconciliation of additions to property, plant and equipment to total capital expenditures:
(In millions)202520242023
Additions to property, plant and equipment$1,808 $1,056 $937 
Increase/(decrease) in capital accruals170 (6)82 
Other(22)— — 
Total capital expenditures$1,956 $1,050 $1,019 
v3.25.4
Leases Disclosure (Tables)
 12 Months Ended
Dec. 31, 2025
Leases [Abstract]  
Lease, Cost [Table Text Block]
The components of lease cost were as follows:
202520242023
(In millions)Related PartyThird
Party		Related
Party		Third
Party		Related
Party		Third
Party
Components of lease costs:
Operating lease costs$15 $60 $14 $58 $14 $56 
Finance lease cost:
Amortization of ROU assets— 2 — 1 — 1 
Interest on lease liabilities — 1 — — — — 
Total finance lease cost— 3 — 1 — 1 
Variable lease cost4 14 4 12 4 10 
Short-term lease cost1 70 1 71 1 61 
Total lease cost$20 $147 $19 $142 $19 $128 
Supplemental Balance Sheet Disclosures [Text Block]
Supplemental balance sheet data related to leases were as follows:
December 31, 2025December 31, 2024
(In millions, except % and years)Related PartyThird PartyRelated PartyThird Party
Operating leases
Assets
Right of use assets$239 $276 $226$273
Liabilities
Operating lease liabilities2 53 245
Long-term operating lease liabilities237 217 224217
Total operating lease liabilities$239 $270 $226$262
Weighted average remaining lease term40 years7 years42 years8 years
Weighted average discount rate5.8 %4.3 %5.8 %4.2 %
Finance leases
Assets
Property, plant and equipment, gross$12 $10
Less: Accumulated depreciation6 5
Property, plant and equipment, net6 5
Liabilities
Long-term debt due within one year2 1
Long-term debt4 5
Total finance lease liabilities$6 $6
Weighted average remaining lease term21 years22 years
Weighted average discount rate5.8 %6.0 %
Lessee, Operating Lease, Liability, to be Paid, Maturity
As of December 31, 2025, maturities of lease liabilities for operating lease obligations and finance lease obligations having initial or remaining non-cancellable lease terms in excess of one year are as follows:
(In millions)Related Party Operating
Leases		Third Party Operating
Leases 		Finance
Leases
2026$16 $62 $3 
202716 54 2 
202816 47 — 
202915 36 — 
203015 28 — 
2031 and thereafter537 84 7 
Gross lease payments615 311 12 
Less: Imputed interest376 41 6 
Total lease liabilities$239 $270 $6 
Finance Lease, Liability, to be Paid, Maturity
As of December 31, 2025, maturities of lease liabilities for operating lease obligations and finance lease obligations having initial or remaining non-cancellable lease terms in excess of one year are as follows:
(In millions)Related Party Operating
Leases		Third Party Operating
Leases 		Finance
Leases
2026$16 $62 $3 
202716 54 2 
202816 47 — 
202915 36 — 
203015 28 — 
2031 and thereafter537 84 7 
Gross lease payments615 311 12 
Less: Imputed interest376 41 6 
Total lease liabilities$239 $270 $6 
Operating Lease, Lease Income [Table Text Block]
Lease revenues included on the Consolidated Statements of Income during 2025, 2024 and 2023 were as follows:
202520242023
(In millions)Related PartyThird
Party		Related PartyThird
Party		Related PartyThird
Party
Operating leases:
Rental income$889 $260 $853 $251 $822 $243 
Sales-type leases:
Interest income (Sales-type rental revenue - fixed minimum)431 113 455 114 467 114 
Interest income (Revenue from variable lease payments)17 38 20 22 33 22 
Sales-type lease revenue$448 $151 $475 $136 $500 $136 
Sales-type Lease, Lease Income [Table Text Block]
Lease revenues included on the Consolidated Statements of Income during 2025, 2024 and 2023 were as follows:
202520242023
(In millions)Related PartyThird
Party		Related PartyThird
Party		Related PartyThird
Party
Operating leases:
Rental income$889 $260 $853 $251 $822 $243 
Sales-type leases:
Interest income (Sales-type rental revenue - fixed minimum)431 113 455 114 467 114 
Interest income (Revenue from variable lease payments)17 38 20 22 33 22 
Sales-type lease revenue$448 $151 $475 $136 $500 $136 
Lessor, Operating Lease, Payment to be Received, Fiscal Year Maturity [Table Text Block]
The following is a schedule of minimum future rental payments to be received on the non-cancellable operating leases as of December 31, 2025:
(In millions)Related PartyThird PartyTotal
2026$835 $107 $942 
2027721 80 801 
2028418 73 491 
2029264 71 335 
2030254 58 312 
2031 and thereafter519 182 701 
Total minimum future rentals$3,011 $571 $3,582 
Sales-type and Direct Financing Leases, Lease Receivable, Maturity [Table Text Block]
Annual minimum undiscounted lease payment receipts under our sales-type leases were as follows as of December 31, 2025:
(In millions)Related PartyThird PartyTotal
2026$472 $181 $653 
2027390 163 553 
2028109 154 263 
202956 146 202 
203056 138 194 
2031 and thereafter63 903 966 
Total minimum future rentals 1,146 1,685 2,831 
Less: Imputed interest456 691 1,147 
Lease receivable(1)
$690 $994 $1,684 
Current lease receivables(2)
$269 $108 $377 
Long-term lease receivables(3)
421 886 1,307 
Unguaranteed residual assets(3)
263 117 380 
Total sales-type lease assets$953 $1,111 $2,064 
(1)    This amount does not include the unguaranteed residual assets.
(2)    The related-party balance is presented in Current assets - related parties and the third-party balance is presented in Receivables, net in the Consolidated Balance Sheets.
(3)    The related-party balance is presented in Noncurrent assets - related parties and the third-party balance is presented in Other noncurrent assets in the Consolidated Balance Sheets.
Schedule of Property Subject to or Available for Operating Lease [Table Text Block]
The following schedule summarizes MPLX’s investment in assets held under operating lease by major classes as of December 31, 2025 and 2024:
December 31,
(In millions)20252024
Pipelines$681 $689 
Refining logistics1,774 1,430 
Terminals1,440 1,310 
Marine126 126 
Gathering and transportation111 86 
Processing and fractionation1,017 1,039 
Land, building and other161 171 
Total property, plant and equipment5,310 4,851 
Less: accumulated depreciation2,731 2,378 
Property, plant and equipment, net$2,579 $2,473 
v3.25.4
Commitments and Contingencies (Tables)
 12 Months Ended
Dec. 31, 2025
Commitments and Contingencies Disclosure [Abstract]  
Contractual Obligation, Fiscal Year Maturity Schedule
MPLX executed various third-party transportation, terminalling, and gathering and processing agreements that obligate us to minimum volume, throughput or payment commitments over the remaining terms, which range from less than one year to seven years. After the minimum volume commitments are met in these agreements, MPLX pays additional amounts based on throughput. These agreements may include escalation clauses based on various inflationary indices; however, those potential increases have not been incorporated in minimum fees due under these agreements presented below. The minimum future payments under these agreements as of December 31, 2025 are as follows:
(In millions)
2026$163 
2027146 
2028132 
202946 
203012 
2031 and thereafter10 
Total$509 
v3.25.4
Description of Business and Basis of Presentation (Details)
 12 Months Ended
Mar. 27, 2012
Dec. 31, 2025
Limited Liability Company or Limited Partnership, Business Organization and Operations [Abstract]    
Date of partnership formation Mar. 27, 2012  
Number of reportable segments   2
v3.25.4
Summary of Principal Accounting Policies (Details) - USD ($)
$ in Millions
Dec. 31, 2025
Dec. 31, 2024
Accounting Policies [Abstract]    
Asset Retirement Obligation $ 45 $ 41
v3.25.4
Acquisitions and Other Transactions (Northwind Midstream) (Details) - USD ($)
$ in Billions
Aug. 29, 2025
Aug. 11, 2025
Senior Notes    
Business Combination [Line Items]    
Debt Instrument, Face Amount   $ 4.5
Northwind Midstream    
Business Combination [Line Items]    
Payments to Acquire Businesses, Gross $ 2.4  
Business Combination, Voting Equity Interest Acquired, Percentage 100.00%  
Acquired Finite-Lived Intangible Assets, Weighted Average Useful Life 15 years  
v3.25.4
Acquisitions and Other Transactions (Northwind Midstream - Assets Acquired and Liabilities Assumed) (Details) - USD ($)
$ in Millions
Dec. 31, 2025
Aug. 29, 2025
Dec. 31, 2024
Dec. 31, 2023
Liabilities assumed:        
Goodwill $ 8,755   $ 7,645 $ 7,645
Northwind Midstream        
Assets acquired:        
Business Combination, Recognized Asset Acquired, Cash and Cash Equivalent 17      
Business Combination, Recognized Asset Acquired, Receivable, Current 11      
Business Combination, Recognized Asset Acquired, Other Asset, Current 1      
Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment 1,169      
Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill 951      
Business Combination, Recognized Asset Acquired, Other Asset, Noncurrent 2      
Business Combination, Recognized Asset Acquired, Asset 2,151      
Liabilities assumed:        
Business Combination, Recognized Liability Assumed, Accounts Payable, Current 22      
Business Combination, Recognized Liability Assumed, Accrued Property, Plant and Equipment, Current 84      
Business Combination, Recognized Liability Assumed, Accrued Liabilities, Current 9      
Business Combination, Recognized Liability Assumed, Other Liability, Current 1      
Business Combination, Recognized Liability Assumed, Operating Lease Liability, Long-term 1      
Business Combination, Recognized Liability Assumed, Liability 117      
Recognized Identifiable Assets Acquired and Liabilities Assumed, Net 2,034      
Goodwill 379      
Business Combination, Recognized Asset Acquired to Liability Assumed, Excess (Less), and Goodwill $ 2,413      
Northwind Midstream | Previously Reported        
Assets acquired:        
Business Combination, Recognized Asset Acquired, Cash and Cash Equivalent   $ 17    
Business Combination, Recognized Asset Acquired, Receivable, Current   11    
Business Combination, Recognized Asset Acquired, Other Asset, Current   1    
Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment   1,182    
Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill   951    
Business Combination, Recognized Asset Acquired, Other Asset, Noncurrent   2    
Business Combination, Recognized Asset Acquired, Asset   2,164    
Liabilities assumed:        
Business Combination, Recognized Liability Assumed, Accounts Payable, Current   15    
Business Combination, Recognized Liability Assumed, Accrued Property, Plant and Equipment, Current   84    
Business Combination, Recognized Liability Assumed, Accrued Liabilities, Current   6    
Business Combination, Recognized Liability Assumed, Other Liability, Current   1    
Business Combination, Recognized Liability Assumed, Operating Lease Liability, Long-term   1    
Business Combination, Recognized Liability Assumed, Liability   107    
Recognized Identifiable Assets Acquired and Liabilities Assumed, Net   2,057    
Goodwill   356    
Business Combination, Recognized Asset Acquired to Liability Assumed, Excess (Less), and Goodwill   2,413    
Northwind Midstream | Revision of Prior Period, Adjustment        
Assets acquired:        
Business Combination, Recognized Asset Acquired, Cash and Cash Equivalent   0    
Business Combination, Recognized Asset Acquired, Receivable, Current   0    
Business Combination, Recognized Asset Acquired, Other Asset, Current   0    
Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment   (13)    
Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill   0    
Business Combination, Recognized Asset Acquired, Other Asset, Noncurrent   0    
Business Combination, Recognized Asset Acquired, Asset   (13)    
Liabilities assumed:        
Business Combination, Recognized Liability Assumed, Accounts Payable, Current   7    
Business Combination, Recognized Liability Assumed, Accrued Property, Plant and Equipment, Current   0    
Business Combination, Recognized Liability Assumed, Accrued Liabilities, Current   3    
Business Combination, Recognized Liability Assumed, Other Liability, Current   0    
Business Combination, Recognized Liability Assumed, Operating Lease Liability, Long-term   0    
Business Combination, Recognized Liability Assumed, Liability   10    
Recognized Identifiable Assets Acquired and Liabilities Assumed, Net   (23)    
Goodwill   23    
Business Combination, Recognized Asset Acquired to Liability Assumed, Excess (Less), and Goodwill   $ 0    
v3.25.4
Acquisitions and Other Transactions (Divestiture of Rockies Operations) (Details) - USD ($)
$ in Millions
 12 Months Ended
Nov. 12, 2025
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]        
Gain (Loss) on Disposition of Assets   $ 161 $ (3) $ 14
Disposal Group, Not Discontinued Operations | Rockies Operations        
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]        
Disposal Group, Including Discontinued Operation, Consideration $ 980      
Gain (Loss) on Disposition of Assets $ 159      
v3.25.4
Acquisitions and Other Transactions (BANGL, LLC Acquisitions) (Details) - USD ($)
$ in Millions
 12 Months Ended
Jul. 03, 2025
Jul. 01, 2025
Jul. 31, 2024
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Business Combination [Line Items]            
Investments - acquisitions and contributions       $ 1,008 $ 464 $ 98
Equity Interest in Acquiree, Remeasurement Gain       $ 484 $ 20 $ 92
BANGL, LLC            
Business Combination [Line Items]            
Equity Method Investment, Additional Ownership Acquired     20.00%      
Investments - acquisitions and contributions     $ 210      
Ownership percentage     45.00%      
Basis difference     $ 156      
BANGL, LLC            
Business Combination [Line Items]            
Payments to Acquire Businesses, Gross   $ 703        
Equity Method Investment, Remaining Ownership Interest Purchased   55.00%        
Equity Interest in Acquiree, Remeasurement Gain   $ 484        
Business Combination, Voting Equity Interest Acquired, Percentage   100.00%        
Business Combination Purchase Price Allocation Goodwill Expected Tax Deductible Percent   55.00%        
Repayments of Debt $ 656          
Business Combination, Contingent Consideration, Range of Outcomes, Maximum, Amount   $ 275        
Acquired Finite-Lived Intangible Assets, Weighted Average Useful Life   11 years        
BANGL, LLC | Minimum            
Business Combination [Line Items]            
Alternative Investment, Measurement Input   0.11        
Alternative Investment, Valuation Technique [Extensible Enumeration]   Valuation Technique, Discounted Cash Flow [Member]        
BANGL, LLC | Maximum            
Business Combination [Line Items]            
Alternative Investment, Measurement Input   0.12        
Alternative Investment, Valuation Technique [Extensible Enumeration]   Valuation Technique, Discounted Cash Flow [Member]        
v3.25.4
Acquisitions and Other Transactions (BANGL, LLC Acquisitions - Total Consideration) (Details) - USD ($)
$ in Millions
 12 Months Ended
Jul. 01, 2025
Dec. 31, 2025
 [1],[2]
Dec. 31, 2024
Dec. 31, 2023
Business Combination [Line Items]        
Business Combination, Fair Value of Contingent Consideration at Acquisition Date   $ 234 $ 0 $ 0
BANGL, LLC        
Business Combination [Line Items]        
Payments to Acquire Businesses, Gross $ 703      
Business Combination, Fair Value of Contingent Consideration at Acquisition Date 234      
Business Combination, Consideration Transferred 937      
Business Combination, Achieved in Stages, Preacquisition Equity Interest in Acquiree, Fair Value 766      
Business Combination, Consideration Transferred and Preacquisition Equity Interest in Acquiree $ 1,703      
[1] Liability recorded in the third quarter of 2025 related to the BANGL Acquisition earnout provision.
[2] See Note 4 – BANGL, LLC Acquisitions.
v3.25.4
Acquisitions and Other Transactions (BANGL, LLC Acquisitions - Assets and Liabilities Purchased) (Details) - USD ($)
$ in Millions
Dec. 31, 2025
Jul. 01, 2025
Dec. 31, 2024
Dec. 31, 2023
Business Combination [Line Items]        
Goodwill $ 8,755   $ 7,645 $ 7,645
BANGL, LLC        
Business Combination [Line Items]        
Business Combination, Recognized Asset Acquired, Cash and Cash Equivalent   $ 18    
Business Combination, Recognized Asset Acquired, Other Asset, Current   4    
Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment   1,550    
Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill   77    
Business Combination, Recognized Asset Acquired, Asset, Noncurrent   22    
Business Combination, Recognized Asset Acquired, Asset   1,671    
Business Combination, Recognized Liability Assumed, Long-Term Debt, Current   46    
Business Combination, Recognized Liability Assumed, Other Liability, Current   42    
Business Combination, Recognized Liability Assumed, Long-Term Debt, Noncurrent   610    
Business Combination, Recognized Liability Assumed, Liability, Noncurrent   1    
Business Combination, Recognized Liability Assumed, Liability   699    
Recognized Identifiable Assets Acquired and Liabilities Assumed, Net   972    
Goodwill   731    
Business Combination, Recognized Asset Acquired to Liability Assumed, Excess (Less), and Goodwill   $ 1,703    
v3.25.4
Acquisitions and Other Transactions (Matterhorn) (Details) - USD ($)
$ in Millions
 12 Months Ended
Jun. 16, 2025
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Business Combination [Line Items]        
Investments - acquisitions and contributions   $ 1,008 $ 464 $ 98
Natural Gas & NGL Services [Member]        
Business Combination [Line Items]        
Basis difference   $ 124 $ 198  
MXP Parent, LLC        
Business Combination [Line Items]        
Equity Method Investment, Additional Ownership Acquired 5.00%      
Ownership percentage 10.00%      
Basis difference $ 124      
MXP Parent, LLC | Property, Plant and Equipment        
Business Combination [Line Items]        
Basis difference 63      
MXP Parent, LLC | Customer-Related Intangible Assets        
Business Combination [Line Items]        
Basis difference 61      
MXP Parent, LLC | Natural Gas & NGL Services [Member]        
Business Combination [Line Items]        
Investments - acquisitions and contributions $ 151      
v3.25.4
Acquisitions and Other Transactions (Whiptail Midstream) (Details) - USD ($)
$ in Millions
 12 Months Ended
Mar. 11, 2025
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Business Combination [Line Items]        
Proceeds from Previous Acquisition   $ 3,316 $ 622 $ 246
Whiptail Midstream Acquisition        
Business Combination [Line Items]        
Proceeds from Previous Acquisition $ 235      
Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment 170      
Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill 41      
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed, Net Working Capital $ 24      
v3.25.4
Acquisitions and Other Transactions (Whistler Joint Venture Transaction) (Details) - USD ($)
$ in Millions
 12 Months Ended
May 29, 2024
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
May 28, 2024
Business Combination [Line Items]          
Investments - redemptions, repayments, return of capital and sales proceeds   $ 293 $ 146 $ 3  
WPC Parent, LLC          
Business Combination [Line Items]          
Gain (Loss) on Disposition of Stock in Subsidiary or Equity Method Investee $ 151        
Investments - redemptions, repayments, return of capital and sales proceeds $ 134        
WPC Parent, LLC | Enbridge Inc.          
Business Combination [Line Items]          
Ownership percentage 19.00%        
WPC Parent, LLC | MPLX LP [Member]          
Business Combination [Line Items]          
Ownership percentage 30.40%        
Whistler Pipeline LLC [Member] | MPLX LP [Member]          
Business Combination [Line Items]          
Ownership percentage         37.50%
v3.25.4
Acquisitions and Other Transactions (Utica Midstream Acquisition) (Details) - USD ($)
$ in Millions
 12 Months Ended
Mar. 22, 2024
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Business Combination [Line Items]        
Equity Interest in Acquiree, Remeasurement Gain   $ 484 $ 20 $ 92
Utica Midstream        
Business Combination [Line Items]        
Payments to Acquire Businesses, Gross $ 625      
Business Combination, Voting Equity Interest Acquired, Percentage 100.00%      
Recognized Identifiable Assets Acquired and Liabilities Assumed, Net $ 625      
Business Combination, Recognized Asset Acquired, Other Asset, Noncurrent $ 507      
Ohio Gathering Company L.L.C.        
Business Combination [Line Items]        
Business Combination, Achieved in Stages, Preacquisition and Acquired Equity Interests in Acquiree, Percentage 73.00%      
Basis difference $ 75      
Ohio Condensate Company, L.L.C.        
Business Combination [Line Items]        
Business Combination, Achieved in Stages, Preacquisition and Acquired Equity Interests in Acquiree, Percentage 100.00%      
Equity Interest in Acquiree, Percentage 62.00%      
Equity Interest in Acquiree, Remeasurement Gain $ 20      
v3.25.4
Acquisitions and Other Transactions (MarkWest Torñado GP, L.L.C.) (Details) - USD ($)
$ in Millions
 12 Months Ended
Dec. 15, 2023
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Business Combination [Line Items]        
Contract with Customer, Asset, before Allowance for Credit Loss, Noncurrent   $ 4 $ 0 $ 1
Equity method investments   4,798 4,531  
Equity Interest in Acquiree, Remeasurement Gain   $ 484 $ 20 $ 92
MarkWest Tornado GP, L.L.C.        
Business Combination [Line Items]        
Equity Method Investment, Remaining Ownership Interest Purchased 40.00%      
Payments to Acquire Additional Interest in Subsidiaries $ 303      
Payments to Acquire Businesses, Gross 270      
Contract with Customer, Asset, before Allowance for Credit Loss, Noncurrent $ 33      
Business Combination, Achieved in Stages, Preacquisition and Acquired Equity Interests in Acquiree, Percentage 100.00%      
Equity Interest in Acquiree, Percentage 60.00%      
Equity method investments $ 311      
Equity Interest in Acquiree, Remeasurement Gain 92      
Recognized Identifiable Assets Acquired and Liabilities Assumed, Net $ 673      
v3.25.4
Acquisitions and Other Transactions (MarkWest Tornado GP, L.L.C. - Assets Acquired and Liabilities Assumed) (Details) - MarkWest Tornado GP, L.L.C.
$ in Millions
Dec. 15, 2023
USD ($)
Business Combination [Line Items]  
Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment $ 585
Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill 75
Recognized Identifiable Assets Acquired and Liabilities Assumed, Working Capital, Net 30
Recognized Identifiable Other Long-term Assets Acquired and Liabilities Assumed, Net (17)
Recognized Identifiable Assets Acquired and Liabilities Assumed, Net $ 673
v3.25.4
Investments and Noncontrolling Interest (Equity Method Investments) (Details) - USD ($)
$ in Millions
 12 Months Ended
May 29, 2024
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Jul. 31, 2024
Schedule of Equity Method Investments [Line Items]          
Equity method investments   $ 4,798 $ 4,531    
Investments - redemptions, repayments, return of capital and sales proceeds   293 146 $ 3  
BANGL, LLC          
Schedule of Equity Method Investments [Line Items]          
Ownership percentage         45.00%
Equity Method Investment, Additional Ownership Acquired         20.00%
MarkWest EMG Jefferson Dry Gas Gathering Company, L.L.C.(4)          
Schedule of Equity Method Investments [Line Items]          
Contribution of Property   125      
Investments - redemptions, repayments, return of capital and sales proceeds   42      
WPC Parent, LLC          
Schedule of Equity Method Investments [Line Items]          
Investments - redemptions, repayments, return of capital and sales proceeds $ 134        
Crude Oil and Products Logistics [Member]          
Schedule of Equity Method Investments [Line Items]          
Equity method investments   $ 1,581 1,595    
Crude Oil and Products Logistics [Member] | Illinois Extension Pipeline Company, L.L.C.          
Schedule of Equity Method Investments [Line Items]          
Ownership percentage   35.00%      
Equity method investments   $ 208 218    
Crude Oil and Products Logistics [Member] | LOOP LLC          
Schedule of Equity Method Investments [Line Items]          
Ownership percentage   41.00%      
Equity method investments   $ 313 310    
Crude Oil and Products Logistics [Member] | MarEn Bakken Company LLC(1)          
Schedule of Equity Method Investments [Line Items]          
Ownership percentage   25.00%      
Equity method investments [1]   $ 502 526    
Crude Oil and Products Logistics [Member] | Other VIEs and Non-VIEs [Member]          
Schedule of Equity Method Investments [Line Items]          
Equity method investments [2]   $ 558 541    
Crude Oil and Products Logistics [Member] | Bakken Pipeline System | Indirect Ownership Interest          
Schedule of Equity Method Investments [Line Items]          
Ownership percentage   9.19%      
Natural Gas & NGL Services [Member]          
Schedule of Equity Method Investments [Line Items]          
Equity method investments   $ 3,217 2,936    
Natural Gas & NGL Services [Member] | Rockies Operations          
Schedule of Equity Method Investments [Line Items]          
Equity method investments     129    
Natural Gas & NGL Services [Member] | Other VIEs and Non-VIEs [Member]          
Schedule of Equity Method Investments [Line Items]          
Equity method investments [2]   565 $ 418    
Natural Gas & NGL Services [Member] | BANGL, LLC          
Schedule of Equity Method Investments [Line Items]          
Ownership percentage [3]     45.00%    
Equity method investments [3]   $ 0 $ 281    
Natural Gas & NGL Services [Member] | MarkWest EMG Jefferson Dry Gas Gathering Company, L.L.C.(4)          
Schedule of Equity Method Investments [Line Items]          
Ownership percentage   67.00%      
Equity method investments   $ 407 [4] 329    
Natural Gas & NGL Services [Member] | MarkWest Utica EMG, L.L.C.          
Schedule of Equity Method Investments [Line Items]          
Ownership percentage   61.00%      
Equity method investments   $ 890 742    
Natural Gas & NGL Services [Member] | Ohio Gathering Company L.L.C.          
Schedule of Equity Method Investments [Line Items]          
Ownership percentage   32.00%      
Equity method investments [5]   $ 444 470    
Natural Gas & NGL Services [Member] | Ohio Gathering Company L.L.C. | Indirect Ownership Interest          
Schedule of Equity Method Investments [Line Items]          
Ownership percentage   41.00%      
Natural Gas & NGL Services [Member] | Sherwood Midstream LLC          
Schedule of Equity Method Investments [Line Items]          
Ownership percentage   50.00%      
Equity method investments   $ 475 488    
Natural Gas & NGL Services [Member] | WPC Parent, LLC          
Schedule of Equity Method Investments [Line Items]          
Ownership percentage   30.00%      
Equity method investments   $ 273 208    
Natural Gas & NGL Services [Member] | Texas City Logistics LLC          
Schedule of Equity Method Investments [Line Items]          
Ownership percentage   50.00%      
Equity method investments   $ 163 $ 0    
[1] The investment in MarEn Bakken Company LLC includes our 9.19 percent indirect interest in a joint venture (“Dakota Access”) that owns and operates the Dakota Access Pipeline and Energy Transfer Crude Oil Pipeline projects (collectively, the “Bakken Pipeline system”).
[2] Included within Other are certain equity method investments that have been deemed to be VIEs. The December 31, 2024 Natural Gas and NGL Services value includes $129 million in investments associated with the Rockies, which were divested in the fourth quarter 2025.
[3] At December 31, 2024, we owned a 45 percent interest in BANGL. On July 1, 2025, we acquired the remaining 55 percent interest in BANGL. As a result of acquiring the remaining interest, we obtained control and now consolidate BANGL.
[4] On March 31, 2025, MPLX contributed a wholly-owned subsidiary with a fair value of $125 million to MarkWest EMG Jefferson Dry Gas Gathering Company, L.L.C. As a result of the transaction, MPLX received special distributions of $42 million in 2025, which are reflected as a return of capital on the Consolidated Statement of Cash Flows.
[5] MPLX also holds a 41 percent indirect interest in OGC through our ownership interest in MarkWest Utica EMG, L.L.C.
v3.25.4
Investments and Noncontrolling Interests (Summary of Equity Method Investment Financial Information) (Details) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Schedule of Equity Method Investments [Line Items]      
Revenues and other income $ 12,998 $ 11,933 $ 11,281
Costs and expenses 7,055 6,645 6,381
Net income 4,952 4,357 3,966
Assets, Current 3,994 3,276  
Liabilities, Current 3,249 3,235  
Equity Method Investment, Nonconsolidated Investee or Group of Investees      
Schedule of Equity Method Investments [Line Items]      
Revenues and other income 3,959 3,594 3,262
Costs and expenses 1,579 1,535 1,331
Income from operations 2,380 2,059 1,930
Net income 1,854 1,631 1,634
Assets, Current 1,347 1,570 1,531
Assets, Noncurrent 20,199 17,927 13,860
Liabilities, Current 1,044 746 979
Liabilities, Noncurrent $ 7,011 $ 6,711 $ 4,856
v3.25.4
Investments and Noncontrolling Interests (Narrative) (Details) - USD ($)
$ in Millions
Dec. 31, 2025
Dec. 31, 2024
Natural Gas & NGL Services [Member]    
Schedule of Equity Method Investments [Line Items]    
Basis difference $ 124 $ 198
Basis difference, not amortized 0 31
Crude Oil and Products Logistics [Member]    
Schedule of Equity Method Investments [Line Items]    
Basis difference 283 291
Basis difference, not amortized $ 167 $ 167
v3.25.4
Related Party Agreements and Transactions (Narrative) (Detail) - Related Party
 12 Months Ended
Dec. 31, 2025
Fuels Distribution [Member]  
Related Party Transaction [Line Items]  
Term Of Agreements 10 years
Renewal Term Agreement 5 years
Marine Services Equipment [Member]  
Related Party Transaction [Line Items]  
Renewal Term Agreement 3 years
Number of renewals 2
Co-location Agreements [Member]  
Related Party Transaction [Line Items]  
Term Of Agreements 50 years
Marine Management Services [Member]  
Related Party Transaction [Line Items]  
Term Of Agreements 5 years
Renewal Term Agreement 5 years
Maximum | Marine Services Equipment [Member]  
Related Party Transaction [Line Items]  
Term Of Agreements 3 years
Operating Agreements [Member] | Minimum  
Related Party Transaction [Line Items]  
Term Of Agreements 1 year
Operating Agreements [Member] | Maximum  
Related Party Transaction [Line Items]  
Term Of Agreements 10 years
v3.25.4
Related Party Agreements and Transactions (Intercompany Loans with Related Parties) (Detail) - Revolving Credit Facility - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Related Party Transaction [Line Items]      
Repayments of Related Party Debt $ 50 $ 0 $ 0
Proceeds from Related Party Debt 50 0 $ 0
Related Party      
Related Party Transaction [Line Items]      
Line of Credit Facility, Current Borrowing Capacity $ 1,500    
Debt Instrument, Description of Variable Rate Basis one-month term SOFR adjusted upward by 0.10 percent plus 1.25 percent    
Interest rate during period 5.68%    
Line of Credit, Current $ 0 $ 0  
v3.25.4
Related Party Agreements and Transactions (Summary of Revenue by Income Statement RP Line Item) (Detail) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Related Party      
Related Party Transaction [Line Items]      
Sales Revenue, Goods, Related Party, Net Zero $ 627 $ 754 $ 739
v3.25.4
Related Party Agreements and Transactions (Summary of Expenses by Income Statement RP Line Item) (Detail) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Related Party Transaction [Line Items]      
General and administrative expenses $ 446 $ 427 $ 379
Marathon Petroleum Corporation [Member]      
Related Party Transaction [Line Items]      
General and administrative expenses 299 289 262
Construction-in-progress | Marathon Petroleum Corporation [Member]      
Related Party Transaction [Line Items]      
Property, Plant and Equipment, Additions $ 230 $ 182 $ 94
v3.25.4
Related Party Agreements and Transactions (Summary of Balance Sheet by RP Line Item) (Details) - USD ($)
$ in Millions
Dec. 31, 2025
Dec. 31, 2024
Related Party Transaction [Line Items]    
Receivables, less allowance for expected credit loss $ 735 $ 718
Lease receivables [1] 377  
Other current assets 51 29
Long-term lease receivables [2] 1,307  
Long-term lease receivables 276 273
Unguaranteed residual asset [2] 380  
Related Party    
Related Party Transaction [Line Items]    
Receivables, less allowance for expected credit loss 624 620
Lease receivables 269 [1] 204
Prepaid 5 5
Other current assets 1 1
Other Receivables, Net, Current 899 830
Long-term lease receivables 421 [2] 677
Long-term lease receivables 239 226
Unguaranteed residual asset 263 [2] 189
Long-term receivables 39 28
Other Receivable, after Allowance for Credit Loss, Noncurrent 962 1,120
MPC loan agreement and other payables(1) [3] 290 288
Deferred revenue 107 106
Operating lease liabilities 2 2
Other Liabilities, Current 399 396
Long-term operating lease liabilities 237 224
Other Liabilities, Noncurrent 364 334
Related Party | Deferred Revenue [Domain]    
Related Party Transaction [Line Items]    
Other Liabilities, Noncurrent 127 110
Related Party | Revolving Credit Facility    
Related Party Transaction [Line Items]    
Line of Credit, Current $ 0 $ 0
[1] The related-party balance is presented in Current assets - related parties and the third-party balance is presented in Receivables, net in the Consolidated Balance Sheets.
[2] The related-party balance is presented in Noncurrent assets - related parties and the third-party balance is presented in Other noncurrent assets in the Consolidated Balance Sheets.
[3] There were no borrowings outstanding on the MPC Loan Agreement as of December 31, 2025 or December 31, 2024.
v3.25.4
Equity (Changes in Partners Capital, Unit Rollforward) (Details) - shares
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Stockholders Equity [Line Items]        
Units outstanding 1,015,702,040 1,017,142,290 1,003,498,875 1,001,020,616
Unit-based compensation awards 147,670 141,985 196,428  
Conversion of Series A preferred units(1) 6,166,965 [1] 21,078,998 [1] 2,281,831  
Units redeemed in unit repurchase program (7,754,885) (7,577,568) 0  
Related Party        
Stockholders Equity [Line Items]        
Units outstanding 647,415,452      
[1] Certain Series A preferred unitholders have exercised their rights to convert their Series A preferred units into common units as discussed in Note 9.
v3.25.4
Repurchase Program (Details) - USD ($)
$ / shares in Units, $ in Millions
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Aug. 05, 2025
Aug. 02, 2022
Equity, Class of Treasury Stock [Line Items]          
Number of common units repurchased 7,754,885 7,577,568 0    
Cash Paid for Units Repurchased [1] $ 400 $ 326 $ 0    
Average cost per unit(1) [1] $ 51.58 $ 43.04 $ 0    
Remaining Authorized Repurchase Amount $ 1,120        
Share Repurchase Authorization August 2025          
Equity, Class of Treasury Stock [Line Items]          
Authorized Amount       $ 1,000  
Share Repurchase Authorization August 2022          
Equity, Class of Treasury Stock [Line Items]          
Authorized Amount         $ 1,000
[1] Cash paid for common units repurchased and average cost per unit includes commissions paid to brokers during the period.
v3.25.4
Equity (Cash Distributions) (Details) - USD ($)
$ / shares in Units, $ in Millions
 12 Months Ended
Feb. 17, 2026
Feb. 09, 2026
Jan. 29, 2026
Feb. 15, 2023
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Distribution Made to Limited Partner [Line Items]              
Cash Distributions Declared         $ 4,138 $ 3,705 $ 3,355
Distributions Declared, Per Unit         $ 4.066 $ 3.613 $ 3.250
Common Unit-holders Public              
Distribution Made to Limited Partner [Line Items]              
Cash Distributions Declared         $ 4,138 $ 3,678 $ 3,256
Series A Preferred Stock [Member]              
Distribution Made to Limited Partner [Line Items]              
Cash Distributions Declared         0 27 94
Series B Preferred Stock [Member]              
Distribution Made to Limited Partner [Line Items]              
Cash Distributions Declared         $ 0 $ 0 [1] $ 5
Distribution date       Feb. 15, 2023      
Subsequent Event              
Distribution Made to Limited Partner [Line Items]              
Distribution declaration date     Jan. 29, 2026        
Cash Distributions Declared     $ 1,092        
Distributions Declared, Per Unit     $ 1.0765        
Subsequent Event | Common Unit-holders Public              
Distribution Made to Limited Partner [Line Items]              
Distribution date Feb. 17, 2026            
Distribution date of record   Feb. 09, 2026          
[1] 2023 period includes the portion of the $21 million distribution paid to the Series B preferred unitholders on February 15, 2023 that was earned during the period prior to the redemption.
v3.25.4
Series B Preferred Units (Details) - USD ($)
$ / shares in Units, $ in Millions
 12 Months Ended
Feb. 15, 2023
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Partners' Capital Account, Distributions   $ 4,062 $ 3,603 $ 3,243
Series B Preferred Stock [Member]        
Partners' Capital Account, Units, Redeemed 600,000      
Preferred Stock, Dividend Rate, Percentage 6.875%      
Preferred Stock, Redemption Price Per Share $ 1,000      
Preferred Stock, Redemption Terms MPLX exercised its right to redeem all 600,000 units of 6.875 percent Fixed-to-Floating Rate Cumulative Redeemable Perpetual Preferred Units (the “Series B preferred units”). MPLX paid unitholders the Series B preferred unit redemption price of $1,000 per unit.      
Partners' Capital Account, Distributions $ 21      
Distribution date Feb. 15, 2023      
v3.25.4
Net Income Per Limited Partner Unit (Basic and Diluted Earnings Per Unit) (Detail) - USD ($)
$ / shares in Units, shares in Millions, $ in Millions
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Net income attributable to MPLX LP:      
Net income attributable to MPLX LP(1): [1] $ 4,912 $ 4,317 $ 3,928
Undistributed Earnings (Loss) Allocated to Participating Securities, Basic 3 9 16
Undistributed Earnings (Loss) Allocated to Participating Securities, Diluted 3 9 16
Impact of redemption of Series B preferred units 0 0 5
Net Income Available to Common Unitholders, Basic 4,909 4,281 3,808
Net Income Available to Common Unitholders, Diluted $ 4,909 $ 4,281 $ 3,808
Weighted average units outstanding:      
Basic (shares) 1,019 1,016 1,001
Diluted (shares) 1,019 1,017 1,002
Net income attributable to MPLX LP per limited partner unit:      
Basic (in USD per unit) $ 4.82 $ 4.21 $ 3.80
Diluted (in USD per unit) $ 4.82 $ 4.21 $ 3.80
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount 1 1 1
Series A Preferred Stock [Member]      
Net income attributable to MPLX LP:      
Distributions declared on preferred units $ 0 $ 27 $ 94
Series B Preferred Stock [Member]      
Net income attributable to MPLX LP:      
Distributions declared on preferred units $ 0 $ 0 $ 5
[1] Allocation of net income attributable to MPLX LP assumes all earnings for the period have been distributed based on the distribution priorities applicable to the period.
v3.25.4
Redeemable Preferred Units (Narrative) (Details) - USD ($)
$ / shares in Units, $ in Millions
 12 Months Ended
Jan. 29, 2026
May 13, 2016
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Redeemable Noncontrolling Interest [Line Items]          
Distributions Declared, Per Unit     $ 4.066 $ 3.613 $ 3.250
Series A Preferred, Units, Converted     6,166,965 [1] 21,078,998 [1] 2,281,831
Series A Preferred Stock [Member]          
Redeemable Noncontrolling Interest [Line Items]          
Series A preferred, Units Issued   30,800,000      
Preferred Stock, Dividend Rate, Percentage   6.50%      
Units issued, price per unit   $ 32.50      
Proceeds from issuance of preferred units   $ 984      
Preferred units, dividend rate, per-dollar-amount   $ 0.528125      
Series A preferred, Units Outstanding     0 6,000,000  
Common Unit-holders Public          
Redeemable Noncontrolling Interest [Line Items]          
Series A Preferred, Units, Converted     6,000,000 21,000,000 2,000,000
Subsequent Event          
Redeemable Noncontrolling Interest [Line Items]          
Distribution declaration date Jan. 29, 2026        
Distributions Declared, Per Unit $ 1.0765        
[1] Certain Series A preferred unitholders have exercised their rights to convert their Series A preferred units into common units as discussed in Note 9.
v3.25.4
Segment Information (Details)
 12 Months Ended
Dec. 31, 2025
Segment Reporting [Abstract]  
Number of reportable segments 2
v3.25.4
Segment Information - Revenues and Adjusted EBITDA (Details) - USD ($)
$ in Millions
 12 Months Ended
Jun. 16, 2025
Aug. 01, 2024
Jul. 31, 2024
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Segment Reporting, Revenue Reconciling Item [Line Items]            
Revenue from Contract with Customer, Excluding Assessed Tax       $ 9,726 $ 9,189 $ 8,733
Sales-type lease revenue       151 136 136
Income from equity method investments       697 802 600
Capital expenditures       1,956 1,050 1,019
Total segment revenues and other income       12,998 11,933 11,281
Investments - acquisitions and contributions       1,008 464 98
Equity Interest in Acquiree, Remeasurement Gain       484 20 92
BANGL, LLC            
Segment Reporting, Revenue Reconciling Item [Line Items]            
Investments - acquisitions and contributions     $ 210      
Wink to Webster Pipeline LLC [Member]            
Segment Reporting, Revenue Reconciling Item [Line Items]            
Investments - acquisitions and contributions   $ 18        
Nonrelated Party            
Segment Reporting, Revenue Reconciling Item [Line Items]            
Rental Income       260 251 243
Sales-type lease revenue       151 136 136
Other Income       179 50 34
Operating Segments            
Segment Reporting, Revenue Reconciling Item [Line Items]            
Adjusted EBITDA       7,017 6,764 6,269
Segment Reconciling Items            
Segment Reporting, Revenue Reconciling Item [Line Items]            
Income from equity method investments       697 802 600
Crude Oil and Products Logistics [Member]            
Segment Reporting, Revenue Reconciling Item [Line Items]            
Revenue from Contract with Customer, Excluding Assessed Tax       4,840 4,561 4,353
Crude Oil and Products Logistics [Member] | Nonrelated Party            
Segment Reporting, Revenue Reconciling Item [Line Items]            
Total segment revenues and other income       751 746 701
Crude Oil and Products Logistics [Member] | Operating Segments            
Segment Reporting, Revenue Reconciling Item [Line Items]            
Rental Income       923 882 857
Sales-type lease revenue       448 475 500
Income from equity method investments       243 269 270
Other Income       121 152 68
Adjusted EBITDA [1]       4,547 4,375 4,134
Capital expenditures       538 482 414
Investments - acquisitions and contributions       0 (93) [2] (8)
Total segment revenues and other income [3]       6,575 6,339 6,048
Operating Expenses       2,173 2,097 2,006
Segment Reporting, Other Segment Item, Amount [4]       (145) (133) (92)
Crude Oil and Products Logistics [Member] | Operating Segments | Pro rata share of JV debt repayment            
Segment Reporting, Revenue Reconciling Item [Line Items]            
Investments - acquisitions and contributions       (92)    
Natural Gas & NGL Services [Member]            
Segment Reporting, Revenue Reconciling Item [Line Items]            
Revenue from Contract with Customer, Excluding Assessed Tax       4,886 4,628 4,380
Natural Gas & NGL Services [Member] | MXP Parent, LLC            
Segment Reporting, Revenue Reconciling Item [Line Items]            
Investments - acquisitions and contributions $ 151          
Consideration Transferred, Contingent Consideration       13    
Natural Gas & NGL Services [Member] | Pro rata share of JV interest in Rio Bravo Pipeline project | WPC Parent, LLC            
Segment Reporting, Revenue Reconciling Item [Line Items]            
Investments - acquisitions and contributions       (49)    
Natural Gas & NGL Services [Member] | Nonrelated Party            
Segment Reporting, Revenue Reconciling Item [Line Items]            
Total segment revenues and other income       6,210 5,297 4,902
Natural Gas & NGL Services [Member] | Operating Segments            
Segment Reporting, Revenue Reconciling Item [Line Items]            
Rental Income       226 222 208
Sales-type lease revenue       151 136 136
Income from equity method investments       454 533 [5] 330
Other Income       222 55 87
Adjusted EBITDA [1]       2,470 2,389 2,135
Capital expenditures       1,418 568 605
Investments - acquisitions and contributions       (794) [2] (143) [2] (90)
Total segment revenues and other income [3]       6,423 5,594 5,233
Operating Expenses       1,716 1,704 1,564
Segment Reporting, Other Segment Item, Amount [4]       422 (60) (64)
Purchased product costs       1,815 1,561 1,598
Equity Interest in Acquiree, Remeasurement Gain [6]       484 20 92
Service [Member] | Crude Oil and Products Logistics [Member] | Operating Segments            
Segment Reporting, Revenue Reconciling Item [Line Items]            
Revenue from Contract with Customer, Excluding Assessed Tax       4,824 4,543 4,335
Service [Member] | Natural Gas & NGL Services [Member] | Operating Segments            
Segment Reporting, Revenue Reconciling Item [Line Items]            
Revenue from Contract with Customer, Excluding Assessed Tax       2,468 2,407 2,189
Product [Member] | Crude Oil and Products Logistics [Member] | Operating Segments            
Segment Reporting, Revenue Reconciling Item [Line Items]            
Revenue from Contract with Customer, Excluding Assessed Tax       16 18 18
Product [Member] | Natural Gas & NGL Services [Member] | Operating Segments            
Segment Reporting, Revenue Reconciling Item [Line Items]            
Revenue from Contract with Customer, Excluding Assessed Tax       $ 2,418 $ 2,221 $ 2,191
[1] See below for the reconciliation from Segment Adjusted EBITDA to Net income.
[2] Investments in unconsolidated affiliates in the Crude Oil and Products Logistics segment includes a contribution of $92 million in 2024 to Dakota Access to fund our share of a debt repayment by the joint venture and excludes $18 million in 2024 related to acquisition of an additional interest in Wink to Webster Pipeline LLC. Investments in unconsolidated affiliates in the Natural Gas and NGL Services segment includes cash contributions to several joint ventures to fund current growth capital projects in 2025 and excludes $151 million in 2025 related to acquisition of an additional interest in the joint venture that owns and operates the Matterhorn Express Pipeline, a $49 million capital contribution in 2025 to WPC Parent, LLC to purchase Enbridge’s special membership interest in the Rio Bravo Pipeline project, a $13 million payment in 2025 related to earnout associated with MXP Parent, LLC, and $210 million in 2024 related to the acquisition of additional interests in BANGL, LLC.
[3] Within the total segment revenues and other income amounts presented above, third-party revenues for the Crude Oil and Products Logistics segment were $751 million, $746 million and $701 million for the years ended December 31, 2025, 2024 and 2023, respectively. Third-party revenues for the Natural Gas and NGL Services segment were $6,210 million, $5,297 million and $4,902 million for the years ended December 31, 2025, 2024 and 2023, respectively.
[4] Other segment items in the Crude Oil and Products Logistics segment include income from equity method investments, distributions and adjustments related to equity method investments, equity-based compensation and other miscellaneous items. Other segment items in the Natural Gas and NGL Services segment include income from and gain on equity method investments, distributions and adjustments related to equity method investments, gain on sale of assets, transaction-related costs, unrealized derivative gain/loss and other miscellaneous items.
[5] Includes a $151 million gain related to the dilution of ownership interest in connection with the Whistler Joint Venture Transaction in 2024.
[6] Gain on equity method investments represents the gain on remeasurement of our existing equity method investment in BANGL in conjunction with the BANGL Acquisition in 2025, the gain on remeasurement of our existing equity method investment in OCC in conjunction with the Utica Midstream Acquisition in 2024, and the gain on remeasurement of our existing equity method investment in Torñado in conjunction with the purchase of the remaining joint venture interest in 2023.
v3.25.4
Segment Information - Reconciliation Adjusted EBITDA to Net income (Details) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Segment Reporting Information [Line Items]      
Depreciation and amortization $ 1,351 $ 1,283 $ 1,213
Income from equity method investments 697 802 600
Gain on sales-type leases and equity method investment 484 20 92
Net income 4,952 4,357 3,966
Gain (Loss) on Disposition of Assets (161) 3 (14)
Operating Segments      
Segment Reporting Information [Line Items]      
Adjusted EBITDA 7,017 6,764 6,269
Operating Segments | Crude Oil and Products Logistics [Member]      
Segment Reporting Information [Line Items]      
Adjusted EBITDA [1] 4,547 4,375 4,134
Depreciation and amortization 546 526 530
Income from equity method investments 243 269 270
Operating Segments | Natural Gas & NGL Services [Member]      
Segment Reporting Information [Line Items]      
Adjusted EBITDA [1] 2,470 2,389 2,135
Depreciation and amortization 805 757 683
Income from equity method investments 454 533 [2] 330
Segment Reconciling Items      
Segment Reporting Information [Line Items]      
Depreciation and amortization [3] 1,351 1,283 1,213
Interest and Other Financial Costs 983 921 923
Income from equity method investments 697 802 600
Distributions/adjustments related to equity method investments 962 928 774
Business Combination, Separately Recognized Transaction, Acquisition-Related Cost, Expensed (33) [4] 0 0
Gain on sales-type leases and equity method investment 484 0 92
Adjusted EBITDA attributable to noncontrolling interests 44 44 42
Garyville incident response costs 0 0 (16) [5]
Other [6] (120) (121) (111)
Gain (Loss) on Disposition of Assets $ 159 $ 0 $ 0
[1] See below for the reconciliation from Segment Adjusted EBITDA to Net income.
[2] Includes a $151 million gain related to the dilution of ownership interest in connection with the Whistler Joint Venture Transaction in 2024.
[3] Depreciation and amortization attributable to Crude Oil and Products Logistics was $546 million, $526 million and $530 million for the years ended December 31, 2025, 2024 and 2023, respectively. Depreciation and amortization attributable to Natural Gas and NGL Services was $805 million, $757 million and $683 million for the years ended December 31, 2025, 2024 and 2023, respectively.
[4] Transaction-related costs include costs associated with the Northwind Midstream Acquisition, the BANGL Acquisition and the divestiture of the Rockies gathering and processing operations discussed in Note 4.
[5] In August 2023, a naphtha release and resulting fire occurred at our Garyville Tank Farm resulting in the loss of four storage tanks with a combined shell capacity of 894 thousand barrels. We incurred $16 million of incident response costs, net of insurance recoveries, during the year ended December 31, 2023.
[6] Includes unrealized derivative gain/(loss), equity-based compensation, provision for income taxes and other miscellaneous items
v3.25.4
Major Customers and Concentration of Credit Risk (Details) - Revenue Benchmark [Member] - Customer Concentration Risk
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Nonrelated Party      
Concentration Risk [Line Items]      
Concentration risk, percentage 10.00%   10.00%
Related Party      
Concentration Risk [Line Items]      
Concentration risk, percentage [1] 48.00% 49.00% 50.00%
Crude Oil and Products Logistics [Member] | Related Party      
Concentration Risk [Line Items]      
Concentration risk, percentage 88.00% 88.00% 88.00%
Natural Gas & NGL Services [Member] | Related Party      
Concentration Risk [Line Items]      
Concentration risk, percentage [1] 2.00% 4.00% 5.00%
[1] The percent calculations for the year ended December 31, 2025 exclude a $484 million gain on remeasurement of our existing equity method investment in BANGL in conjunction with the BANGL Acquisition and a $159 million gain on divestiture of the Rockies. The percent calculations for the year ended December 31, 2024 exclude a gain of $151 million related to the dilution of ownership interest in connection with the Whistler Joint Venture Transaction. The percent calculations for the year ended December 31, 2023 exclude a $92 million gain on remeasurement of our existing equity investment in Torñado. See Note 4 for additional information.
v3.25.4
Inventories (Summary of Inventories) (Details) - USD ($)
$ in Millions
Dec. 31, 2025
Dec. 31, 2024
Inventory Disclosure [Abstract]    
NGLs $ 5 $ 5
Line fill 2 18
Spare parts, materials and supplies 165 157
Total inventories $ 172 $ 180
v3.25.4
Property, Plant and Equipment (Summary of Property, Plant and Equipment) (Detail) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Property, Plant and Equipment [Line Items]      
Property, plant and equipment, gross $ 31,759 $ 28,404  
Less accumulated depreciation 10,061 9,250  
Property, plant and equipment, net 21,698 19,154  
Capitalized interest 42 19 $ 15
Crude Oil and Products Logistics [Member]      
Property, Plant and Equipment [Line Items]      
Property, plant and equipment, gross 13,809 13,189  
Natural Gas & NGL Services [Member]      
Property, Plant and Equipment [Line Items]      
Property, plant and equipment, gross 17,950 15,215  
Pipelines And Related Assets [Member] | Crude Oil and Products Logistics [Member]      
Property, Plant and Equipment [Line Items]      
Property, plant and equipment, gross 6,908 6,627  
Refining Logistics and related assets [Member] | Crude Oil and Products Logistics [Member]      
Property, Plant and Equipment [Line Items]      
Property, plant and equipment, gross 1,990 1,867  
Terminals and related assets [Member] | Crude Oil and Products Logistics [Member]      
Property, Plant and Equipment [Line Items]      
Property, plant and equipment, gross 1,869 1,726  
Marine [Member] | Crude Oil and Products Logistics [Member]      
Property, Plant and Equipment [Line Items]      
Property, plant and equipment, gross 1,188 1,149  
Land Building Office Equipment And Other [Member] | Crude Oil and Products Logistics [Member]      
Property, Plant and Equipment [Line Items]      
Property, plant and equipment, gross 1,627 1,619  
Land Building Office Equipment And Other [Member] | Natural Gas & NGL Services [Member]      
Property, Plant and Equipment [Line Items]      
Property, plant and equipment, gross 437 541  
Gas Gathering And Transportation [Member] | Natural Gas & NGL Services [Member]      
Property, Plant and Equipment [Line Items]      
Property, plant and equipment, gross 9,379 7,789  
Processing and fractionation [Member] | Natural Gas & NGL Services [Member]      
Property, Plant and Equipment [Line Items]      
Property, plant and equipment, gross 6,896 6,611  
Construction-in-progress | Crude Oil and Products Logistics [Member]      
Property, Plant and Equipment [Line Items]      
Property, plant and equipment, gross 227 201  
Construction-in-progress | Natural Gas & NGL Services [Member]      
Property, Plant and Equipment [Line Items]      
Property, plant and equipment, gross $ 1,238 $ 274  
Minimum | Pipelines And Related Assets [Member] | Crude Oil and Products Logistics [Member]      
Property, Plant and Equipment [Line Items]      
Estimated useful lives 15 years    
Minimum | Refining Logistics and related assets [Member] | Crude Oil and Products Logistics [Member]      
Property, Plant and Equipment [Line Items]      
Estimated useful lives 15 years    
Minimum | Terminals and related assets [Member] | Crude Oil and Products Logistics [Member]      
Property, Plant and Equipment [Line Items]      
Estimated useful lives 15 years    
Minimum | Marine [Member] | Crude Oil and Products Logistics [Member]      
Property, Plant and Equipment [Line Items]      
Estimated useful lives 15 years    
Minimum | Land Building Office Equipment And Other [Member] | Crude Oil and Products Logistics [Member]      
Property, Plant and Equipment [Line Items]      
Estimated useful lives 5 years    
Minimum | Land Building Office Equipment And Other [Member] | Natural Gas & NGL Services [Member]      
Property, Plant and Equipment [Line Items]      
Estimated useful lives 5 years    
Minimum | Gas Gathering And Transportation [Member] | Natural Gas & NGL Services [Member]      
Property, Plant and Equipment [Line Items]      
Estimated useful lives 5 years    
Minimum | Processing and fractionation [Member] | Natural Gas & NGL Services [Member]      
Property, Plant and Equipment [Line Items]      
Estimated useful lives 10 years    
Maximum | Pipelines And Related Assets [Member] | Crude Oil and Products Logistics [Member]      
Property, Plant and Equipment [Line Items]      
Estimated useful lives 50 years    
Maximum | Refining Logistics and related assets [Member] | Crude Oil and Products Logistics [Member]      
Property, Plant and Equipment [Line Items]      
Estimated useful lives 20 years    
Maximum | Terminals and related assets [Member] | Crude Oil and Products Logistics [Member]      
Property, Plant and Equipment [Line Items]      
Estimated useful lives 40 years    
Maximum | Marine [Member] | Crude Oil and Products Logistics [Member]      
Property, Plant and Equipment [Line Items]      
Estimated useful lives 20 years    
Maximum | Land Building Office Equipment And Other [Member] | Crude Oil and Products Logistics [Member]      
Property, Plant and Equipment [Line Items]      
Estimated useful lives 50 years    
Maximum | Land Building Office Equipment And Other [Member] | Natural Gas & NGL Services [Member]      
Property, Plant and Equipment [Line Items]      
Estimated useful lives 40 years    
Maximum | Gas Gathering And Transportation [Member] | Natural Gas & NGL Services [Member]      
Property, Plant and Equipment [Line Items]      
Estimated useful lives 40 years    
Maximum | Processing and fractionation [Member] | Natural Gas & NGL Services [Member]      
Property, Plant and Equipment [Line Items]      
Estimated useful lives 40 years    
v3.25.4
Goodwill and Intangibles (Goodwill) (Narrative) (Details)
$ in Millions
 12 Months Ended
Dec. 31, 2025
USD ($)
Dec. 31, 2024
USD ($)
Dec. 31, 2023
USD ($)
Goodwill and Intangible Assets Disclosure [Abstract]      
Goodwill, Impairment Loss $ 0 $ 0  
Goodwill $ 8,755 $ 7,645 $ 7,645
Number of reporting units with goodwill 4    
Total Number of Reporting Units 5    
v3.25.4
Goodwill and Intangibles (Reconciliation of Goodwill) (Details) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Goodwill [Line Items]      
Gross goodwill $ 11,896    
Goodwill, Impaired, Accumulated Impairment Loss (3,141)    
Goodwill 8,755 $ 7,645 $ 7,645
Goodwill, Impairment Loss 0 0  
Goodwill, Acquired During Period [1] 1,110    
Crude Oil and Products Logistics [Member]      
Goodwill [Line Items]      
Gross goodwill 7,645    
Goodwill, Impaired, Accumulated Impairment Loss 0   0
Goodwill 7,645 7,645 7,645
Goodwill, Impairment Loss 0 0  
Goodwill, Acquired During Period 0    
Natural Gas & NGL Services [Member]      
Goodwill [Line Items]      
Gross goodwill 4,251    
Goodwill, Impaired, Accumulated Impairment Loss (3,141)   (3,141)
Goodwill 1,110 0 $ 0
Goodwill, Impairment Loss 0 $ 0  
Goodwill, Acquired During Period [1] $ 1,110    
[1] Acquisitions in 2025 are inclusive of the Northwind Midstream Acquisition and the BANGL Acquisition.
v3.25.4
Goodwill and Intangibles (Intangible Assets) (Details) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Finite-Lived Intangible Assets [Line Items]    
Gross Intangibles $ 2,483 $ 1,646
Accumulated amortization [1] (1,086) (1,128)
Intangibles, net 1,397 518
Crude Oil and Products Logistics [Member]    
Finite-Lived Intangible Assets [Line Items]    
Gross Intangibles 308 283
Accumulated amortization [1] (260) (224)
Intangibles, net 48 59
Amortization of Intangible Assets 36 35
Natural Gas & NGL Services [Member]    
Finite-Lived Intangible Assets [Line Items]    
Gross Intangibles 2,175 1,363
Accumulated amortization [1] (826) (904)
Intangibles, net 1,349 459
Amortization of Intangible Assets $ 105 $ 99
[1] Amortization expense attributable to the Crude Oil and Products Logistics segment for the years ended December 31, 2025 and 2024 was $36 million and $35 million, respectively. Amortization expense attributable to the Natural Gas and NGL Services segment for the years ended December 31, 2025 and 2024 was $105 million and $99 million, respectively.
v3.25.4
Goodwill and Intangibles (Future Amortization Expense) (Details)
$ in Millions
Dec. 31, 2025
USD ($)
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract]  
2026 $ 164
2027 136
2028 125
2029 91
2030 91
2031 and thereafter 790
Total future intangibles amortization expense $ 1,397
v3.25.4
Fair Value Measurements - Recurring (Financial Instruments by Valuation Hierarchy) (Details) - Fair Value, Inputs, Level 3 [Member] - USD ($)
$ in Millions
Dec. 31, 2025
Dec. 31, 2024
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Derivative Liability, Subject to Master Netting Arrangement, before Offset $ 41 $ 58
Other current liabilities | Embedded Derivative Financial Instruments [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Derivative Liability, Subject to Master Netting Arrangement, before Offset 6 10
Other Noncurrent Liabilities [Member] | Embedded Derivative Financial Instruments [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Derivative Liability, Subject to Master Netting Arrangement, before Offset $ 35 $ 48
v3.25.4
Fair Value Measurements - Recurring (Significant Unobservable Inputs in Level 3 Valuation) (Details)
 12 Months Ended
Dec. 31, 2025
$ / gal
USD ($)
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]  
Derivative, Average Forward Price | $ / gal 0.72
Embedded Derivative Financial Instruments [Member]  
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]  
Embedded Derivative Renewal Term 5 years
Embedded Derivative Financial Instruments [Member] | Fair Value, Inputs, Level 3 [Member]  
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]  
Fair Value Inputs Probability of Renewal 100.00%
Minimum | Embedded Derivative Financial Instruments [Member] | Fair Value, Inputs, Level 3 [Member]  
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]  
Derivative, Forward Price 0.60
Maximum | Embedded Derivative Financial Instruments [Member] | Fair Value, Inputs, Level 3 [Member]  
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]  
Derivative, Forward Price 1.19
v3.25.4
Fair Value Measurements - Recurring (Changes in Level 3 Measurements) (Details) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]      
Beginning balance $ (58) $ (61)  
Contingent consideration(1) (234) [1],[2] 0 $ 0
Unrealized and realized Gain (Loss) Included in Net Income [3] $ 5 $ (10)  
Fair Value, Net Derivative Asset (Liability), Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] Purchased product costs Purchased product costs  
Settlements $ 10 $ 13  
Ending balance (277) (58) $ (61)
Fair Value, Liability, Recurring Basis, Still Held, Unrealized Gain (Loss) $ 7 $ (7)  
Fair Value, Liability, Recurring Basis, Still Held, Unrealized Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] Purchased product costs Purchased product costs  
[1] Liability recorded in the third quarter of 2025 related to the BANGL Acquisition earnout provision.
[2] See Note 4 – BANGL, LLC Acquisitions.
[3] Gain/(loss) on derivatives embedded in commodity contracts are recorded in Purchased product costs in the Consolidated Statements of Income.
v3.25.4
Fair Value Measurements - Reported (Details) - USD ($)
$ in Millions
Dec. 31, 2025
Dec. 31, 2024
Carrying Value    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Long-Term Debt, Fair Value [1] $ 25,821 $ 21,068
Fair Value    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Long-Term Debt, Fair Value [1] 24,887 19,574
Fair Value, Inputs, Level 3 [Member]    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Derivative Liability, Fair Value, Gross Liability 41 58
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability Value 277 58
Business Combination, Contingent Consideration, Liability $ 236 $ 0
[1] Any amounts outstanding under the MPC Loan Agreement are not included in the table above, as the carrying value approximates fair value. This balance, if any, is reflected in Current liabilities - related parties in the Consolidated Balance Sheets.
v3.25.4
Derivative Financial Instruments (Embedded Derivatives in Commodity Contracts) (Details)
$ in Millions
 12 Months Ended
Dec. 31, 2025
USD ($)
Dec. 31, 2024
USD ($)
Derivative [Line Items]    
Description of Embedded Derivative MPLX has a natural gas purchase commitment embedded in a keep-whole processing agreement with a producer customer in the Southern Appalachia region expiring in December 2027. The customer has the unilateral option to extend the agreement for one five-year term through December 2032. For accounting purposes, the natural gas purchase commitment and the term extending option have been aggregated into a single compound embedded derivative.  
Embedded Derivative Financial Instruments [Member]    
Derivative [Line Items]    
Number of renewals 1  
Derivative, Term of Contract 5 years  
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]    
Derivative [Line Items]    
Embedded Derivative, Fair Value of Embedded Derivative Liability $ 41 $ 58
v3.25.4
Derivative Financial Instruments (Derivatives Income Statement Location) (Details) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Derivative Instruments, Gain (Loss) [Line Items]      
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] Net income Net income Net income
Derivative, Gain (Loss) on Derivative, Net $ 7 $ (9) $ (4)
Purchased product costs      
Derivative Instruments, Gain (Loss) [Line Items]      
Derivative Instruments Not Designated as Hedging Instruments, Realized Gain (Loss), Net (10) (13) (11)
Unrealized Gain (Loss) on Derivatives and Commodity Contracts $ 17 $ 3 $ 0
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] Cost of revenues (excludes items below) Cost of revenues (excludes items below) Cost of revenues (excludes items below)
Derivative, Gain (Loss) on Derivative, Net $ 7 $ (10) $ (11)
Product sales      
Derivative Instruments, Gain (Loss) [Line Items]      
Derivative Instruments Not Designated as Hedging Instruments, Realized Gain (Loss), Net $ 0 $ 1 $ 7
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] Revenue from Contract with Customer, Excluding Assessed Tax, Third parties Revenue from Contract with Customer, Excluding Assessed Tax, Third parties Revenue from Contract with Customer, Excluding Assessed Tax, Third parties
Derivative, Gain (Loss) on Derivative, Net $ 0 $ 1 $ 7
v3.25.4
Debt (Summary of Outstanding Borrowings) (Details) - USD ($)
$ in Millions
 12 Months Ended
Aug. 11, 2025
Mar. 10, 2025
Dec. 31, 2025
Apr. 09, 2025
Feb. 18, 2025
Dec. 31, 2024
Dec. 01, 2024
May 20, 2024
Debt Instrument [Line Items]                
Finance Lease, Liability [1]     $ 6     $ 6    
Debt and capital lease obligations     26,006     21,206    
Unamortized debt issuance costs     174     126    
Unamortized discount     179     132    
Debt, Current     1,502     1,693    
Total long-term debt due after one year     24,151     19,255    
MPLX Revolving Credit Facility due July 2027                
Debt Instrument [Line Items]                
Outstanding balance     0          
MPLX Revolving Credit Facility due July 2024 [Member]                
Debt Instrument [Line Items]                
Outstanding balance           0    
Senior Notes                
Debt Instrument [Line Items]                
Debt Instrument, Face Amount $ 4,500              
Senior Notes | Senior Note Due June 2034                
Debt Instrument [Line Items]                
Interest Rate               5.50%
Debt Instrument, Face Amount               $ 1,650
Senior Notes | Senior Notes Due February 2031                
Debt Instrument [Line Items]                
Interest Rate 4.80%              
Maturity Date Feb. 15, 2031              
Debt Instrument, Face Amount [2] $ 1,250              
Senior Notes | Senior Notes Due January 2033                
Debt Instrument [Line Items]                
Interest Rate 5.00%              
Maturity Date Jan. 15, 2033              
Debt Instrument, Face Amount [2] $ 750              
Senior Notes | Senior Notes Due April 2035                
Debt Instrument [Line Items]                
Interest Rate   5.40%            
Maturity Date   Apr. 01, 2035            
Debt Instrument, Face Amount [3]   $ 1,000            
Senior Notes | Senior Notes Due September 2035                
Debt Instrument [Line Items]                
Interest Rate 5.40%              
Maturity Date Sep. 15, 2035              
Debt Instrument, Face Amount [2] $ 1,500              
Senior Notes | Senior Notes Due April 2055                
Debt Instrument [Line Items]                
Interest Rate   5.95%            
Maturity Date   Apr. 01, 2055            
Debt Instrument, Face Amount [3]   $ 1,000            
Senior Notes | Senior Notes Due September 2055                
Debt Instrument [Line Items]                
Interest Rate 6.20%              
Maturity Date Sep. 15, 2055              
Debt Instrument, Face Amount [2] $ 1,000              
MPLX LP | Senior Notes | Senior Notes Due December 2024 [Member]                
Debt Instrument [Line Items]                
Interest Rate             4.875%  
MPLX LP | Senior Notes | Senior Notes Due February 2025 [Member]                
Debt Instrument [Line Items]                
Long-term debt, gross     $ 0     500    
Interest Rate     4.00%   4.00%      
Maturity Date     Feb. 15, 2025          
MPLX LP | Senior Notes | Senior Notes Due June 2025 [Member]                
Debt Instrument [Line Items]                
Long-term debt, gross     $ 0     1,189    
Interest Rate     4.875% 4.875%        
Maturity Date     Jun. 01, 2025          
MPLX LP | Senior Notes | Senior Notes Due March 2026 [Member]                
Debt Instrument [Line Items]                
Long-term debt, gross     $ 1,500     1,500    
Interest Rate     1.75%          
Maturity Date     Mar. 01, 2026          
MPLX LP | Senior Notes | 4.125% senior notes due March 2027                
Debt Instrument [Line Items]                
Long-term debt, gross     $ 1,250     1,250    
Interest Rate     4.125%          
Maturity Date     Mar. 01, 2027          
MPLX LP | Senior Notes | Senior Notes Due December 2027 [Member]                
Debt Instrument [Line Items]                
Long-term debt, gross     $ 732     732    
Interest Rate     4.25%          
Maturity Date     Dec. 01, 2027          
MPLX LP | Senior Notes | Senior Notes Due March 2028 [Member]                
Debt Instrument [Line Items]                
Long-term debt, gross     $ 1,250     1,250    
Interest Rate     4.00%          
Maturity Date     Mar. 15, 2028          
MPLX LP | Senior Notes | Senior Notes Due February 2029 [Member]                
Debt Instrument [Line Items]                
Long-term debt, gross     $ 750     750    
Interest Rate     4.80%          
Maturity Date     Feb. 15, 2029          
MPLX LP | Senior Notes | Senior Notes Due August 2030 [Member]                
Debt Instrument [Line Items]                
Long-term debt, gross     $ 1,500     1,500    
Interest Rate     2.65%          
Maturity Date     Aug. 15, 2030          
MPLX LP | Senior Notes | Senior Note Due September 2032                
Debt Instrument [Line Items]                
Long-term debt, gross     $ 1,000     1,000    
Interest Rate     4.95%          
Maturity Date     Sep. 01, 2032          
MPLX LP | Senior Notes | Senior Note Due March 2033                
Debt Instrument [Line Items]                
Long-term debt, gross     $ 1,100     1,100    
Interest Rate     5.00%          
Maturity Date     Mar. 01, 2033          
MPLX LP | Senior Notes | Senior Note Due June 2034                
Debt Instrument [Line Items]                
Long-term debt, gross     $ 1,650     1,650    
Interest Rate     5.50%          
Maturity Date     Jun. 01, 2034          
MPLX LP | Senior Notes | Senior Notes Due April 2038 [Member]                
Debt Instrument [Line Items]                
Long-term debt, gross     $ 1,750     1,750    
Interest Rate     4.50%          
Maturity Date     Apr. 15, 2038          
MPLX LP | Senior Notes | 5.200% senior notes due March 2047                
Debt Instrument [Line Items]                
Long-term debt, gross     $ 1,000     1,000    
Interest Rate     5.20%          
Maturity Date     Mar. 01, 2047          
MPLX LP | Senior Notes | Senior Notes Due December 2047 [Member]                
Debt Instrument [Line Items]                
Long-term debt, gross     $ 487     487    
Interest Rate     5.20%          
Maturity Date     Dec. 01, 2047          
MPLX LP | Senior Notes | Senior Notes Due April 2048 [Member]                
Debt Instrument [Line Items]                
Long-term debt, gross     $ 1,500     1,500    
Interest Rate     4.70%          
Maturity Date     Apr. 15, 2048          
MPLX LP | Senior Notes | Senior Notes Due February 2049 [Member]                
Debt Instrument [Line Items]                
Long-term debt, gross     $ 1,500     1,500    
Interest Rate     5.50%          
Maturity Date     Feb. 15, 2049          
MPLX LP | Senior Notes | Senior Note Due March 2052 [Member]                
Debt Instrument [Line Items]                
Long-term debt, gross     $ 1,500     1,500    
Interest Rate     4.95%          
Maturity Date     Mar. 14, 2052          
MPLX LP | Senior Notes | Senior Note Due March 2053                
Debt Instrument [Line Items]                
Long-term debt, gross     $ 500     500    
Interest Rate     5.65%          
Maturity Date     Mar. 01, 2053          
MPLX LP | Senior Notes | Senior Notes Due April 2058 [Member]                
Debt Instrument [Line Items]                
Long-term debt, gross     $ 500     500    
Interest Rate     4.90%          
Maturity Date     Apr. 15, 2058          
MPLX LP | Senior Notes | Senior Notes Due February 2031                
Debt Instrument [Line Items]                
Long-term debt, gross     $ 1,250     0    
Interest Rate     4.80%          
Maturity Date     Feb. 15, 2031          
MPLX LP | Senior Notes | Senior Notes Due January 2033                
Debt Instrument [Line Items]                
Long-term debt, gross     $ 750     0    
Interest Rate     5.00%          
Maturity Date     Jan. 15, 2033          
MPLX LP | Senior Notes | Senior Notes Due April 2035                
Debt Instrument [Line Items]                
Long-term debt, gross     $ 1,000     0    
Interest Rate     5.40%          
Maturity Date     Apr. 01, 2035          
MPLX LP | Senior Notes | Senior Notes Due September 2035                
Debt Instrument [Line Items]                
Long-term debt, gross     $ 1,500     0    
Interest Rate     5.40%          
Maturity Date     Sep. 15, 2035          
MPLX LP | Senior Notes | Senior Notes Due April 2055                
Debt Instrument [Line Items]                
Long-term debt, gross     $ 1,000     0    
Interest Rate     5.95%          
Maturity Date     Apr. 01, 2055          
MPLX LP | Senior Notes | Senior Notes Due September 2055                
Debt Instrument [Line Items]                
Long-term debt, gross     $ 1,000     0    
Interest Rate     6.20%          
Maturity Date     Sep. 15, 2055          
MarkWest | Senior Notes                
Debt Instrument [Line Items]                
Long-term debt, gross     $ 0     11    
Interest Rate     4.875%          
MarkWest | Senior Notes | Senior Notes Due December 2024 [Member]                
Debt Instrument [Line Items]                
Interest Rate             4.875%  
MarkWest | Senior Notes | Senior Notes Due June 2025 [Member]                
Debt Instrument [Line Items]                
Interest Rate       4.875%        
ANDX LP [Member] | Senior Notes                
Debt Instrument [Line Items]                
Long-term debt, gross     $ 31     $ 31    
ANDX LP [Member] | Senior Notes | Minimum                
Debt Instrument [Line Items]                
Interest Rate     4.25%          
ANDX LP [Member] | Senior Notes | Maximum                
Debt Instrument [Line Items]                
Interest Rate     5.20%          
[1] See Note 21 for lease information.
[2] We used a portion of the net proceeds from this offering to fund the Northwind Midstream Acquisition, including the payment of related fees and expenses, and to increase cash and cash equivalents following the recently completed BANGL Acquisition and BANGL Debt Repayment. The remainder of the net proceeds from this offering were used for general partnership purposes.
[3] On April 9, 2025, MPLX used $1.2 billion of the net proceeds from the issuance of senior notes in March 2025 to redeem all of (i) MPLX’s outstanding $1,189 million aggregate principal amount of 4.875 percent senior notes due June 2025 and (ii) MarkWest’s outstanding $11 million aggregate principal amount of 4.875 percent senior notes due June 2025. The remaining net proceeds from this offering were used for general partnership purposes.
v3.25.4
Debt (Summary of Outstanding Borrowings Interest Rates and Table Due Dates) (Details) - Senior Notes
 12 Months Ended
Dec. 31, 2025
Apr. 09, 2025
Feb. 18, 2025
May 20, 2024
Senior Note Due June 2034        
Debt Instrument [Line Items]        
Interest rate, stated percentage       5.50%
MPLX LP | Senior Notes Due February 2025 [Member]        
Debt Instrument [Line Items]        
Interest rate, stated percentage 4.00%   4.00%  
Debt Instrument, Maturity Date Feb. 15, 2025      
MPLX LP | Senior Notes Due June 2025 [Member]        
Debt Instrument [Line Items]        
Interest rate, stated percentage 4.875% 4.875%    
Debt Instrument, Maturity Date Jun. 01, 2025      
MPLX LP | Senior Notes Due March 2026 [Member]        
Debt Instrument [Line Items]        
Interest rate, stated percentage 1.75%      
Debt Instrument, Maturity Date Mar. 01, 2026      
MPLX LP | Senior Notes Due March 2027 [Member]        
Debt Instrument [Line Items]        
Interest rate, stated percentage 4.125%      
Debt Instrument, Maturity Date Mar. 01, 2027      
MPLX LP | Senior Notes Due December 2027 [Member]        
Debt Instrument [Line Items]        
Interest rate, stated percentage 4.25%      
Debt Instrument, Maturity Date Dec. 01, 2027      
MPLX LP | Senior Notes Due March 2028 [Member]        
Debt Instrument [Line Items]        
Interest rate, stated percentage 4.00%      
Debt Instrument, Maturity Date Mar. 15, 2028      
MPLX LP | Senior Notes Due February 2029 [Member]        
Debt Instrument [Line Items]        
Interest rate, stated percentage 4.80%      
Debt Instrument, Maturity Date Feb. 15, 2029      
MPLX LP | Senior Notes Due August 2030 [Member]        
Debt Instrument [Line Items]        
Interest rate, stated percentage 2.65%      
Debt Instrument, Maturity Date Aug. 15, 2030      
MPLX LP | Senior Note Due September 2032        
Debt Instrument [Line Items]        
Interest rate, stated percentage 4.95%      
Debt Instrument, Maturity Date Sep. 01, 2032      
MPLX LP | Senior Note Due March 2033        
Debt Instrument [Line Items]        
Interest rate, stated percentage 5.00%      
Debt Instrument, Maturity Date Mar. 01, 2033      
MPLX LP | Senior Note Due June 2034        
Debt Instrument [Line Items]        
Interest rate, stated percentage 5.50%      
Debt Instrument, Maturity Date Jun. 01, 2034      
MPLX LP | Senior Notes Due April 2038 [Member]        
Debt Instrument [Line Items]        
Interest rate, stated percentage 4.50%      
Debt Instrument, Maturity Date Apr. 15, 2038      
MPLX LP | 5.200% senior notes due March 2047        
Debt Instrument [Line Items]        
Interest rate, stated percentage 5.20%      
Debt Instrument, Maturity Date Mar. 01, 2047      
MPLX LP | Senior Notes Due December 2047 [Member]        
Debt Instrument [Line Items]        
Interest rate, stated percentage 5.20%      
Debt Instrument, Maturity Date Dec. 01, 2047      
MPLX LP | Senior Notes Due April 2048 [Member]        
Debt Instrument [Line Items]        
Interest rate, stated percentage 4.70%      
Debt Instrument, Maturity Date Apr. 15, 2048      
MPLX LP | Senior Notes Due November 2049 [Member]        
Debt Instrument [Line Items]        
Interest rate, stated percentage 5.50%      
Debt Instrument, Maturity Date Feb. 15, 2049      
MPLX LP | Senior Note Due March 2052 [Member]        
Debt Instrument [Line Items]        
Interest rate, stated percentage 4.95%      
Debt Instrument, Maturity Date Mar. 14, 2052      
MPLX LP | Senior Note Due March 2053        
Debt Instrument [Line Items]        
Interest rate, stated percentage 5.65%      
Debt Instrument, Maturity Date Mar. 01, 2053      
MPLX LP | Senior Notes Due April 2058 [Member]        
Debt Instrument [Line Items]        
Interest rate, stated percentage 4.90%      
Debt Instrument, Maturity Date Apr. 15, 2058      
v3.25.4
Debt (Schedule of Debt Payments) (Detail)
$ in Millions
Dec. 31, 2025
USD ($)
Debt Disclosure [Abstract]  
2026 $ 1,503
2027 2,002
2028 1,250
2029 750
2030 $ 1,500
v3.25.4
Debt (Credit Agreements) (Detail)
$ in Millions
 12 Months Ended
Dec. 31, 2025
USD ($)
Dec. 31, 2024
USD ($)
Debt Instrument [Line Items]    
Debt Instrument, Covenant Description The MPLX Credit Agreement contains certain representations and warranties, affirmative and restrictive covenants and events of default that MPLX considers to be usual and customary for an agreement of this type, including a financial covenant that requires MPLX to maintain a ratio of Consolidated Total Debt as of the end of each fiscal quarter to Consolidated EBITDA (both as defined in the MPLX Credit Agreement) for the prior four fiscal quarters of no greater than 5.0 to 1.0 (or 5.5 to 1.0 for up to two fiscal quarters following certain acquisitions). Consolidated EBITDA is subject to adjustments, including for certain acquisitions and dispositions completed and capital projects undertaken during the relevant period. Other covenants restrict MPLX and/or certain of its subsidiaries from incurring debt, creating liens on our assets and entering into transactions with affiliates.  
Debt Instrument, Covenant Compliance As of December 31, 2025, MPLX was in compliance with the covenants contained in the MPLX Credit Agreement.  
MPLX Revolving Credit Facility due July 2027    
Debt Instrument [Line Items]    
Maximum borrowing capacity $ 2,000  
Debt Instrument, Description of Variable Rate Basis Adjusted Term SOFR or the Alternate Base Rate, both as defined in the MPLX Credit Agreement, plus an applicable margin  
Number of renewals 2  
Debt Instrument, Renewal Term 1 year  
Repayments of long-term lines of credit $ 106  
Proceeds from long-term lines of credit 106  
MPLX Revolving Credit Facility due July 2027 | Maximum    
Debt Instrument [Line Items]    
Additional borrowing capacity 1,000  
MPLX Revolving Credit Facility due July 2027 | Letter of Credit    
Debt Instrument [Line Items]    
Maximum borrowing capacity $ 150  
Revolving Credit Facility    
Debt Instrument [Line Items]    
Repayments of long-term lines of credit   $ 0
Proceeds from long-term lines of credit   $ 0
v3.25.4
Debt (Senior Notes) (Details) - USD ($)
$ in Millions
 12 Months Ended
Aug. 11, 2025
Apr. 09, 2025
Mar. 10, 2025
Feb. 18, 2025
Dec. 01, 2024
May 20, 2024
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Series B Preferred Stock [Member]                  
Debt Instrument [Line Items]                  
Payments for Repurchase of Preferred Stock and Preference Stock             $ 0 $ 0 $ 600
Senior Notes                  
Debt Instrument [Line Items]                  
Debt Instrument, Face Amount $ 4,500                
Senior Notes | Senior Note Due June 2034                  
Debt Instrument [Line Items]                  
Interest rate, stated percentage           5.50%      
Percent of par           98.778%      
Debt Instrument, Face Amount           $ 1,650      
Debt Instrument, Issuance Date           May 20, 2024      
Senior Notes | Senior Notes Due December 2024 [Member]                  
Debt Instrument [Line Items]                  
Repayments of Debt         $ 1,150        
Senior Notes | Senior Notes Due February 2031                  
Debt Instrument [Line Items]                  
Interest rate, stated percentage 4.80%                
Percent of par 99.88%                
Debt Instrument, Face Amount [1] $ 1,250                
Debt Instrument, Issuance Date Aug. 11, 2025                
Debt Instrument, Maturity Date Feb. 15, 2031                
Senior Notes | Senior Notes Due January 2033                  
Debt Instrument [Line Items]                  
Interest rate, stated percentage 5.00%                
Percent of par 98.936%                
Debt Instrument, Face Amount [1] $ 750                
Debt Instrument, Issuance Date Aug. 11, 2025                
Debt Instrument, Maturity Date Jan. 15, 2033                
Senior Notes | Senior Notes Due April 2035                  
Debt Instrument [Line Items]                  
Interest rate, stated percentage     5.40%            
Percent of par     99.398%            
Debt Instrument, Face Amount [2]     $ 1,000            
Repayments of Debt   $ 1,200              
Debt Instrument, Issuance Date     Mar. 10, 2025            
Debt Instrument, Maturity Date     Apr. 01, 2035            
Senior Notes | Senior Notes Due September 2035                  
Debt Instrument [Line Items]                  
Interest rate, stated percentage 5.40%                
Percent of par 98.943%                
Debt Instrument, Face Amount [1] $ 1,500                
Debt Instrument, Issuance Date Aug. 11, 2025                
Debt Instrument, Maturity Date Sep. 15, 2035                
Senior Notes | Senior Notes Due April 2055                  
Debt Instrument [Line Items]                  
Interest rate, stated percentage     5.95%            
Percent of par     98.331%            
Debt Instrument, Face Amount [2]     $ 1,000            
Debt Instrument, Issuance Date     Mar. 10, 2025            
Debt Instrument, Maturity Date     Apr. 01, 2055            
Senior Notes | Senior Notes Due September 2055                  
Debt Instrument [Line Items]                  
Interest rate, stated percentage 6.20%                
Percent of par 98.277%                
Debt Instrument, Face Amount [1] $ 1,000                
Debt Instrument, Issuance Date Aug. 11, 2025                
Debt Instrument, Maturity Date Sep. 15, 2055                
MPLX LP | Senior Notes | Senior Note Due June 2034                  
Debt Instrument [Line Items]                  
Interest rate, stated percentage             5.50%    
Debt Instrument, Maturity Date             Jun. 01, 2034    
MPLX LP | Senior Notes | Senior Notes Due December 2024 [Member]                  
Debt Instrument [Line Items]                  
Interest rate, stated percentage         4.875%        
Repayments of Debt         $ 1,149        
MPLX LP | Senior Notes | Senior Notes Due February 2025 [Member]                  
Debt Instrument [Line Items]                  
Interest rate, stated percentage       4.00%     4.00%    
Repayments of Debt       $ 500          
Debt Instrument, Maturity Date             Feb. 15, 2025    
MPLX LP | Senior Notes | Senior Note Due March 2033                  
Debt Instrument [Line Items]                  
Interest rate, stated percentage             5.00%    
Debt Instrument, Maturity Date             Mar. 01, 2033    
MPLX LP | Senior Notes | Senior Note Due March 2053                  
Debt Instrument [Line Items]                  
Interest rate, stated percentage             5.65%    
Debt Instrument, Maturity Date             Mar. 01, 2053    
MPLX LP | Senior Notes | Senior Notes Due February 2031                  
Debt Instrument [Line Items]                  
Interest rate, stated percentage             4.80%    
Debt Instrument, Maturity Date             Feb. 15, 2031    
MPLX LP | Senior Notes | Senior Notes Due January 2033                  
Debt Instrument [Line Items]                  
Interest rate, stated percentage             5.00%    
Debt Instrument, Maturity Date             Jan. 15, 2033    
MPLX LP | Senior Notes | Senior Notes Due April 2035                  
Debt Instrument [Line Items]                  
Interest rate, stated percentage             5.40%    
Debt Instrument, Maturity Date             Apr. 01, 2035    
MPLX LP | Senior Notes | Senior Notes Due September 2035                  
Debt Instrument [Line Items]                  
Interest rate, stated percentage             5.40%    
Debt Instrument, Maturity Date             Sep. 15, 2035    
MPLX LP | Senior Notes | Senior Notes Due April 2055                  
Debt Instrument [Line Items]                  
Interest rate, stated percentage             5.95%    
Debt Instrument, Maturity Date             Apr. 01, 2055    
MPLX LP | Senior Notes | Senior Notes Due September 2055                  
Debt Instrument [Line Items]                  
Interest rate, stated percentage             6.20%    
Debt Instrument, Maturity Date             Sep. 15, 2055    
MarkWest | Senior Notes                  
Debt Instrument [Line Items]                  
Interest rate, stated percentage             4.875%    
MarkWest | Senior Notes | Senior Notes Due December 2024 [Member]                  
Debt Instrument [Line Items]                  
Interest rate, stated percentage         4.875%        
Repayments of Debt         $ 1        
[1] We used a portion of the net proceeds from this offering to fund the Northwind Midstream Acquisition, including the payment of related fees and expenses, and to increase cash and cash equivalents following the recently completed BANGL Acquisition and BANGL Debt Repayment. The remainder of the net proceeds from this offering were used for general partnership purposes.
[2] On April 9, 2025, MPLX used $1.2 billion of the net proceeds from the issuance of senior notes in March 2025 to redeem all of (i) MPLX’s outstanding $1,189 million aggregate principal amount of 4.875 percent senior notes due June 2025 and (ii) MarkWest’s outstanding $11 million aggregate principal amount of 4.875 percent senior notes due June 2025. The remaining net proceeds from this offering were used for general partnership purposes.
v3.25.4
Debt (Senior Notes - Issuances) (Details) - Senior Notes - USD ($)
$ in Millions
 12 Months Ended
Aug. 11, 2025
Apr. 09, 2025
Mar. 10, 2025
Dec. 31, 2025
Debt Instrument [Line Items]        
Debt Instrument, Face Amount $ 4,500      
MarkWest        
Debt Instrument [Line Items]        
Interest rate, stated percentage       4.875%
Senior Notes Due April 2035        
Debt Instrument [Line Items]        
Debt Instrument, Issuance Date     Mar. 10, 2025  
Debt Instrument, Face Amount [1]     $ 1,000  
Interest rate, stated percentage     5.40%  
Percent of par     99.398%  
Debt Instrument, Maturity Date     Apr. 01, 2035  
Repayments of Debt   $ 1,200    
Senior Notes Due April 2035 | MPLX LP [Member]        
Debt Instrument [Line Items]        
Interest rate, stated percentage       5.40%
Debt Instrument, Maturity Date       Apr. 01, 2035
Senior Notes Due April 2055        
Debt Instrument [Line Items]        
Debt Instrument, Issuance Date     Mar. 10, 2025  
Debt Instrument, Face Amount [1]     $ 1,000  
Interest rate, stated percentage     5.95%  
Percent of par     98.331%  
Debt Instrument, Maturity Date     Apr. 01, 2055  
Senior Notes Due April 2055 | MPLX LP [Member]        
Debt Instrument [Line Items]        
Interest rate, stated percentage       5.95%
Debt Instrument, Maturity Date       Apr. 01, 2055
Senior Notes Due February 2031        
Debt Instrument [Line Items]        
Debt Instrument, Issuance Date Aug. 11, 2025      
Debt Instrument, Face Amount [2] $ 1,250      
Interest rate, stated percentage 4.80%      
Percent of par 99.88%      
Debt Instrument, Maturity Date Feb. 15, 2031      
Senior Notes Due February 2031 | MPLX LP [Member]        
Debt Instrument [Line Items]        
Interest rate, stated percentage       4.80%
Debt Instrument, Maturity Date       Feb. 15, 2031
Senior Notes Due January 2033        
Debt Instrument [Line Items]        
Debt Instrument, Issuance Date Aug. 11, 2025      
Debt Instrument, Face Amount [2] $ 750      
Interest rate, stated percentage 5.00%      
Percent of par 98.936%      
Debt Instrument, Maturity Date Jan. 15, 2033      
Senior Notes Due January 2033 | MPLX LP [Member]        
Debt Instrument [Line Items]        
Interest rate, stated percentage       5.00%
Debt Instrument, Maturity Date       Jan. 15, 2033
Senior Notes Due September 2035        
Debt Instrument [Line Items]        
Debt Instrument, Issuance Date Aug. 11, 2025      
Debt Instrument, Face Amount [2] $ 1,500      
Interest rate, stated percentage 5.40%      
Percent of par 98.943%      
Debt Instrument, Maturity Date Sep. 15, 2035      
Senior Notes Due September 2035 | MPLX LP [Member]        
Debt Instrument [Line Items]        
Interest rate, stated percentage       5.40%
Debt Instrument, Maturity Date       Sep. 15, 2035
Senior Notes Due September 2055        
Debt Instrument [Line Items]        
Debt Instrument, Issuance Date Aug. 11, 2025      
Debt Instrument, Face Amount [2] $ 1,000      
Interest rate, stated percentage 6.20%      
Percent of par 98.277%      
Debt Instrument, Maturity Date Sep. 15, 2055      
Senior Notes Due September 2055 | MPLX LP [Member]        
Debt Instrument [Line Items]        
Interest rate, stated percentage       6.20%
Debt Instrument, Maturity Date       Sep. 15, 2055
Senior Notes Due June 2025 [Member] | MPLX LP [Member]        
Debt Instrument [Line Items]        
Interest rate, stated percentage   4.875%   4.875%
Debt Instrument, Maturity Date       Jun. 01, 2025
Repayments of Debt   $ 1,189    
Senior Notes Due June 2025 [Member] | MarkWest        
Debt Instrument [Line Items]        
Interest rate, stated percentage   4.875%    
Repayments of Debt   $ 11    
[1] On April 9, 2025, MPLX used $1.2 billion of the net proceeds from the issuance of senior notes in March 2025 to redeem all of (i) MPLX’s outstanding $1,189 million aggregate principal amount of 4.875 percent senior notes due June 2025 and (ii) MarkWest’s outstanding $11 million aggregate principal amount of 4.875 percent senior notes due June 2025. The remaining net proceeds from this offering were used for general partnership purposes.
[2] We used a portion of the net proceeds from this offering to fund the Northwind Midstream Acquisition, including the payment of related fees and expenses, and to increase cash and cash equivalents following the recently completed BANGL Acquisition and BANGL Debt Repayment. The remainder of the net proceeds from this offering were used for general partnership purposes.
v3.25.4
Debt (Credit Agreements - Activity) (Details) - MPLX Revolving Credit Facility due July 2027
$ in Millions
 12 Months Ended
Dec. 31, 2025
USD ($)
Debt Instrument [Line Items]  
Proceeds from long-term lines of credit $ 106.0
Debt, Weighted Average Interest Rate 7.74%
Repayments of long-term lines of credit $ 106.0
Outstanding balance 0.0
Letters of Credit Outstanding, Amount 0.2
Line of Credit Facility, Remaining Borrowing Capacity $ 2,000.0
Line of Credit Facility, Remaining Borrowing Capacity, Percentage 100.00%
v3.25.4
Net Interest and Other Financial Costs (Details) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Interest expense $ 1,072 $ 963 $ 912
Interest income 68 95 43
Net interest and other financial costs 983 921 923
Interest costs capitalized (42) (19) (15)
Nonrelated Party      
Interest Expense, Other $ 21 $ 72 $ 69
v3.25.4
Revenue Disaggregation of Revenue (Details) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Disaggregation of Revenue [Line Items]      
Total revenues from contracts with customers $ 9,726 $ 9,189 $ 8,733
Non-ASC 606 revenue and other income(1) [1] 3,272 2,744 2,548
Total revenues and other income 12,998 11,933 11,281
Service [Member]      
Disaggregation of Revenue [Line Items]      
Revenue from Contract with Customer, Third parties 2,899 2,770 2,539
Revenue from Contract with Customer, Related Parties 4,393 4,180 3,985
Service, Other [Member]      
Disaggregation of Revenue [Line Items]      
Revenue from Contract with Customer, Third parties 289 357 294
Product [Member]      
Disaggregation of Revenue [Line Items]      
Revenue from Contract with Customer, Third parties 2,002 1,657 1,665
Revenue from Contract with Customer, Related Parties 143 225 250
Crude Oil and Products Logistics [Member]      
Disaggregation of Revenue [Line Items]      
Total revenues from contracts with customers 4,840 4,561 4,353
Crude Oil and Products Logistics [Member] | Service [Member]      
Disaggregation of Revenue [Line Items]      
Revenue from Contract with Customer, Third parties 453 391 369
Revenue from Contract with Customer, Related Parties 4,371 4,152 3,966
Crude Oil and Products Logistics [Member] | Service, Other [Member]      
Disaggregation of Revenue [Line Items]      
Revenue from Contract with Customer, Third parties 0 0 0
Crude Oil and Products Logistics [Member] | Product [Member]      
Disaggregation of Revenue [Line Items]      
Revenue from Contract with Customer, Third parties 4 5 5
Revenue from Contract with Customer, Related Parties 12 13 13
Natural Gas & NGL Services [Member]      
Disaggregation of Revenue [Line Items]      
Total revenues from contracts with customers 4,886 4,628 4,380
Natural Gas & NGL Services [Member] | Service [Member]      
Disaggregation of Revenue [Line Items]      
Revenue from Contract with Customer, Third parties 2,446 2,379 2,170
Revenue from Contract with Customer, Related Parties 22 28 19
Natural Gas & NGL Services [Member] | Service, Other [Member]      
Disaggregation of Revenue [Line Items]      
Revenue from Contract with Customer, Third parties 289 357 294
Natural Gas & NGL Services [Member] | Product [Member]      
Disaggregation of Revenue [Line Items]      
Revenue from Contract with Customer, Third parties 1,998 1,652 1,660
Revenue from Contract with Customer, Related Parties $ 131 $ 212 $ 237
[1] Non-ASC 606 Revenue and other income includes rental income, sales-type lease revenue, income from equity method investments and other income.
v3.25.4
Revenue Contract Balance Rollforward (Details) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Beginning Balance Contract with Customer, Asset, Gross $ 2 $ 3  
Contract with Customer, Asset Increase (Decrease) 13 0  
Contract with Customer, Asset, Reclassified to Receivable [1] 0 (1)  
Ending Balance Contract with Customer, Asset, Gross 15 2  
Contract with Customer, Asset Increase (Decrease), Noncurrent 4 (1)  
Contract with Customer, Non Current Asset Reclassified to Receivable [1] 0 0  
Contract with Customer, Asset, before Allowance for Credit Loss, Noncurrent 4 0 $ 1
Contract with Customer, Liability, Change in Timeframe, Performance Obligation Satisfied, Revenue Recognized 0 0  
Nonrelated Party      
Beginning Balance Deferred Revenue, Current 84 59  
Deferred Revenue, Additions 9 86  
Deferred Revenue, Revenue Recognized [1] (80) (61)  
Ending Balance Deferred Revenue, Current 13 84  
Deferred Revenue, Noncurrent, Period Increase (Decrease) (198) [2] (29)  
Deferred Revenue, Noncurrent, Revenue Recognized [1] 0 0  
Deferred Revenue from Contracts with Customers, Noncurrent 117 315 344
Nonrelated Party | Rockies Operations      
Deferred Revenue, Noncurrent, Period Increase (Decrease) 180    
Related Party      
Beginning Balance Deferred Revenue, Current 106    
Deferred Revenue, Additions 86 90  
Deferred Revenue, Revenue Recognized [1] (91) (66)  
Ending Balance Deferred Revenue, Current 107 106  
Deferred Revenue from Contracts with Customers, Current 66 71 47
Deferred Revenue, Noncurrent, Period Increase (Decrease) 1 15  
Deferred Revenue, Noncurrent, Revenue Recognized [1] 0 0  
Deferred Revenue from Contracts with Customers, Noncurrent $ 45 $ 44 $ 29
[1] No significant revenue was recognized related to past performance obligations in the period presented.
[2] Long-term deferred revenue deletions include $180 million removed in connection with the Rockies divestiture. See Note 4 for additional information related to the Rockies divestiture.
v3.25.4
Revenue Remaining Performance Obligations (Details)
$ in Millions
Dec. 31, 2025
USD ($)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]  
Revenue, Remaining Performance Obligation, Amount $ 5,800
Contract with Customer, Liability 241
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01  
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]  
Revenue, Remaining Performance Obligation, Amount $ 2,000
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period 1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-01-01  
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]  
Revenue, Remaining Performance Obligation, Amount $ 1,900
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period 1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2027-01-01  
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]  
Revenue, Remaining Performance Obligation, Amount $ 700
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period 1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2028-01-01  
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]  
Revenue, Remaining Performance Obligation, Amount $ 300
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period 1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2029-01-01  
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]  
Revenue, Remaining Performance Obligation, Amount $ 200
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period 1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2030-01-01  
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]  
Revenue, Remaining Performance Obligation, Amount $ 700
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period 14 years
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2043-10-01  
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]  
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period 20 years
v3.25.4
Supplemental Cash Flow Information - Summary of Supplemental Cash Flow Information (Details) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Supplemental Cash Flow Information [Abstract]      
Interest paid (net of amounts capitalized) $ 913 $ 940 $ 893
Income taxes paid 7 6 7
Payments on operating leases 64 71 71
Principal payments under finance lease obligations 2 1 1
Non-cash investing and financing activities:      
Transfers of property, plant and equipment to lease receivable 0 0 (8)
ROU assets obtained in exchange for new operating lease obligations 53 47 21
ROU assets obtained in exchange for new finance lease obligations 3 1 0
Book Value of Equity Method Investment [1] 282 4 311
Contribution of Net Assets 115 [2] 0 0
Business Combination, Fair Value of Contingent Consideration at Acquisition Date $ 234 [3],[4] $ 0 $ 0
Other Significant Noncash Transaction, Consideration Given 24 — —
[1] Represents the book value of MPLX’s equity method investment in BANGL in 2025, OCC in 2024 and Torñado in 2023 prior to MPLX buying out the remaining interest in these entities. See Note 4 for additional information.
[2] Represents the book value of assets contributed by MPLX to a joint venture.
[3] Liability recorded in the third quarter of 2025 related to the BANGL Acquisition earnout provision.
[4] See Note 4 – BANGL, LLC Acquisitions.
v3.25.4
Supplemental Cash Flow Information - Summary of Reconciliation of Additions to Property, Plant and Equipment to Total Capital Expenditures (Details) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Supplemental Cash Flow Information [Abstract]      
Additions to property, plant and equipment $ 1,808 $ 1,056 $ 937
Increase/(decrease) in capital accruals 170 (6) 82
Capital Expenditure 1,956 1,050 1,019
Other Adjustments to Capital Expenditures $ (22) $ 0 $ 0
v3.25.4
Leases Lessee Disclosures (Details) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Lessee, Lease, Description [Line Items]      
Right of use assets, net $ 276 $ 273  
Operating Lease, Liability, Noncurrent 217 217  
Finance Lease, Liability [1] 6 $ 6  
Finance Lease, Liability, to be Paid, Year One 3    
Finance Lease, Liability, to be Paid, Year Two 2    
Finance Lease, Liability, to be Paid, Year Three 0    
Finance Lease, Liability, to be Paid, Year Four 0    
Finance Lease, Liability, to be Paid, Year Five 0    
Finance Lease, Liability, to be Paid, after Year Five 7    
Finance Lease, Liability, Payment, Due 12    
Finance Lease, Liability, Undiscounted Excess Amount $ 6    
Finance Lease, Liability, Statement of Financial Position [Extensible Enumeration] Long-term debt, Long-term debt due within one year Long-term debt, Long-term debt due within one year  
Nonrelated Party      
Lessee, Lease, Description [Line Items]      
Operating lease costs $ 60 $ 58 $ 56
Finance Lease, Right-of-Use Asset, Amortization 2 1 1
Finance Lease, Interest Expense 1 0 0
Finance Lease Cost 3 1 1
Variable lease cost 14 12 10
Short-term lease cost 70 71 61
Total lease cost 147 142 128
Right of use assets, net 276 273  
Operating lease liabilities 53 45  
Operating Lease, Liability, Noncurrent 217 217  
Operating Lease, Liability $ 270 $ 262  
Operating Lease, Weighted Average Remaining Lease Term 7 years 8 years  
Operating Lease, Weighted Average Discount Rate, Percent 4.30% 4.20%  
Finance Lease, Right-of-Use Asset, before Accumulated Amortization $ 12 $ 10  
Finance Lease, Right-of-Use Asset, Accumulated Amortization 6 5  
Finance Lease, Right-of-Use Asset, after Accumulated Amortization 6 5  
Finance Lease, Liability, Current 2 1  
Finance Lease, Liability, Noncurrent 4 5  
Finance Lease, Liability $ 6 $ 6  
Finance Lease, Weighted Average Remaining Lease Term 21 years 22 years  
Finance Lease, Weighted Average Discount Rate, Percent 5.80% 6.00%  
Lessee, Operating Lease, Liability, to be Paid, Year One $ 62    
Lessee, Operating Lease, Liability, to be Paid, Year Two 54    
Lessee, Operating Lease, Liability, to be Paid, Year Three 47    
Lessee, Operating Lease, Liability, to be Paid, Year Four 36    
Lessee, Operating Lease, Liability, to be Paid, Year Five 28    
Lessee, Operating Lease, Liability, to be Paid, after Year Five 84    
Lessee, Operating Lease, Liability, to be Paid 311    
Lessee, Operating Lease, Liability, Undiscounted Excess Amount $ 41    
Finance Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration] Long-term debt due within one year Long-term debt due within one year  
Finance Lease, Liability, Noncurrent, Statement of Financial Position [Extensible Enumeration] Long-term debt Long-term debt  
Related Party      
Lessee, Lease, Description [Line Items]      
Operating lease costs $ 15 $ 14 14
Finance Lease, Right-of-Use Asset, Amortization 0 0 0
Finance Lease, Interest Expense 0 0 0
Finance Lease Cost 0 0 0
Variable lease cost 4 4 4
Short-term lease cost 1 1 1
Total lease cost 20 19 $ 19
Right of use assets, net 239 226  
Operating Lease Liability, Current, Related Party 2 2  
Operating lease liabilities 2 2  
Operating Lease, Liability, Noncurrent, Related Party 237 224  
Operating Lease, Liability, Related Party $ 239 $ 226  
Operating Lease, Weighted Average Remaining Lease Term 40 years 42 years  
Operating Lease, Weighted Average Discount Rate, Percent 5.80% 5.80%  
Lessee, Operating Lease, Liability, to be Paid, Year One $ 16    
Lessee, Operating Lease, Liability, to be Paid, Year Two 16    
Lessee, Operating Lease, Liability, to be Paid, Year Three 16    
Lessee, Operating Lease, Liability, to be Paid, Year Four 15    
Lessee, Operating Lease, Liability, to be Paid, Year Five 15    
Lessee, Operating Lease, Liability, to be Paid, after Year Five 537    
Lessee, Operating Lease, Liability, to be Paid 615    
Lessee, Operating Lease, Liability, Undiscounted Excess Amount $ 376    
Maximum      
Lessee, Lease, Description [Line Items]      
Lessee, Operating Lease, Remaining Lease Term 93 years    
Lessee, Operating Lease, Renewal Term 50 years    
Minimum      
Lessee, Lease, Description [Line Items]      
Lessee, Operating Lease, Remaining Lease Term 1 year    
Lessee, Operating Lease, Renewal Term 1 year    
[1] See Note 21 for lease information.
v3.25.4
Leases Lessor Disclosures (Details) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Lessor, Lease, Description [Line Items]      
Sales-type lease revenue, related parties $ 448 $ 475 $ 500
Sales-type lease revenue 151 136 136
Sales-type Lease, Lease Receivable [1] 1,684    
Sales-type Lease, Unguaranteed Residual Asset [2] 380    
Contributions 21 34 31
Lessor, Operating Lease, Payment to be Received, Year One 942    
Lessor, Operating Lease, Payment to be Received, Year Two 801    
Lessor, Operating Lease, Payment to be Received, Year Three 491    
Lessor, Operating Lease, Payment to be Received, Year Four 335    
Lessor, Operating Lease, Payment to be Received, Year Five 312    
Lessor, Operating Lease, Payment to be Received, after Year Five 701    
Lessor, Operating Lease, Payments to be Received 3,582    
Sales-Type and Direct Financing Leases, Lease Receivable, to be Received, Year One 653    
Sales-Type and Direct Financing Leases, Lease Receivable, to be Received, Year Two 553    
Sales-Type and Direct Financing Leases, Lease Receivable, to be Received, Year Three 263    
Sales-Type and Direct Financing Leases, Lease Receivable, to be Received, Year Four 202    
Sales-Type and Direct Financing Leases, Lease Receivable, to be Received, Year Five 194    
Sales-Type and Direct Financing Leases, Lease Receivable, to be Received, after Year Five 966    
Sales-type and Direct Financing Leases, Lease Receivable, Payments to be Received 2,831    
Sales-type and Direct Financing Leases, Lease Receivable, Undiscounted Excess Amount 1,147    
Net Investment in Lease, before Allowance for Credit Loss, Current [3] 377    
Net Investment in Lease, before Allowance for Credit Loss, Noncurrent [2] 1,307    
Sales-Type Lease, Net Investment in Lease, before Allowance for Credit Loss 2,064    
Property Subject to or Available for Operating Lease, Gross 5,310 4,851  
Accumulated depreciation 2,731 2,378  
Property, Plant and Equipment, Net 2,579 2,473  
Net Investment in Lease, Purchase 221 159 85
Pipelines And Related Assets [Member]      
Lessor, Lease, Description [Line Items]      
Property Subject to or Available for Operating Lease, Gross 681 689  
Refining Logistics and related assets [Member]      
Lessor, Lease, Description [Line Items]      
Property Subject to or Available for Operating Lease, Gross 1,774 1,430  
Terminals and related assets [Member]      
Lessor, Lease, Description [Line Items]      
Property Subject to or Available for Operating Lease, Gross 1,440 1,310  
Marine [Member]      
Lessor, Lease, Description [Line Items]      
Property Subject to or Available for Operating Lease, Gross 126 126  
Gas Gathering And Transportation [Member]      
Lessor, Lease, Description [Line Items]      
Property Subject to or Available for Operating Lease, Gross 111 86  
Processing and fractionation [Member]      
Lessor, Lease, Description [Line Items]      
Property Subject to or Available for Operating Lease, Gross 1,017 1,039  
Land Building Office Equipment And Other [Member]      
Lessor, Lease, Description [Line Items]      
Property Subject to or Available for Operating Lease, Gross 161 171  
Nonrelated Party      
Lessor, Lease, Description [Line Items]      
Operating Lease, Lease Income 260 251 243
Sales-type Lease, Interest Income 113 114 114
Sales-type Lease, Variable Lease Income 38 22 22
Sales-type lease revenue 151 136 136
Sales-type Lease, Lease Receivable [1] 994    
Sales-type Lease, Unguaranteed Residual Asset [2] 117    
Lessor, Operating Lease, Payment to be Received, Year One 107    
Lessor, Operating Lease, Payment to be Received, Year Two 80    
Lessor, Operating Lease, Payment to be Received, Year Three 73    
Lessor, Operating Lease, Payment to be Received, Year Four 71    
Lessor, Operating Lease, Payment to be Received, Year Five 58    
Lessor, Operating Lease, Payment to be Received, after Year Five 182    
Lessor, Operating Lease, Payments to be Received 571    
Sales-Type and Direct Financing Leases, Lease Receivable, to be Received, Year One 181    
Sales-Type and Direct Financing Leases, Lease Receivable, to be Received, Year Two 163    
Sales-Type and Direct Financing Leases, Lease Receivable, to be Received, Year Three 154    
Sales-Type and Direct Financing Leases, Lease Receivable, to be Received, Year Four 146    
Sales-Type and Direct Financing Leases, Lease Receivable, to be Received, Year Five 138    
Sales-Type and Direct Financing Leases, Lease Receivable, to be Received, after Year Five 903    
Sales-type and Direct Financing Leases, Lease Receivable, Payments to be Received 1,685    
Sales-type and Direct Financing Leases, Lease Receivable, Undiscounted Excess Amount 691    
Net Investment in Lease, before Allowance for Credit Loss, Current [3] 108    
Net Investment in Lease, before Allowance for Credit Loss, Noncurrent [2] 886    
Sales-Type Lease, Net Investment in Lease, before Allowance for Credit Loss 1,111    
Related Party      
Lessor, Lease, Description [Line Items]      
Operating Lease, Lease Income 889 853 822
Sales-type Lease, Interest Income 431 455 467
Sales-type Lease, Variable Lease Income 17 20 33
Sales-type lease revenue, related parties 448 475 $ 500
Sales-type Lease, Lease Receivable [1] 690    
Sales-type Lease, Unguaranteed Residual Asset 263 [2] 189  
Lessor, Operating Lease, Payment to be Received, Year One 835    
Lessor, Operating Lease, Payment to be Received, Year Two 721    
Lessor, Operating Lease, Payment to be Received, Year Three 418    
Lessor, Operating Lease, Payment to be Received, Year Four 264    
Lessor, Operating Lease, Payment to be Received, Year Five 254    
Lessor, Operating Lease, Payment to be Received, after Year Five 519    
Lessor, Operating Lease, Payments to be Received 3,011    
Sales-Type and Direct Financing Leases, Lease Receivable, to be Received, Year One 472    
Sales-Type and Direct Financing Leases, Lease Receivable, to be Received, Year Two 390    
Sales-Type and Direct Financing Leases, Lease Receivable, to be Received, Year Three 109    
Sales-Type and Direct Financing Leases, Lease Receivable, to be Received, Year Four 56    
Sales-Type and Direct Financing Leases, Lease Receivable, to be Received, Year Five 56    
Sales-Type and Direct Financing Leases, Lease Receivable, to be Received, after Year Five 63    
Sales-type and Direct Financing Leases, Lease Receivable, Payments to be Received 1,146    
Sales-type and Direct Financing Leases, Lease Receivable, Undiscounted Excess Amount 456    
Net Investment in Lease, before Allowance for Credit Loss, Current 269 [3] 204  
Net Investment in Lease, before Allowance for Credit Loss, Noncurrent 421 [2] $ 677  
Sales-Type Lease, Net Investment in Lease, before Allowance for Credit Loss $ 953    
Maximum      
Lessor, Lease, Description [Line Items]      
Lessor, Operating Lease, Renewal Term 5 years    
Maximum | Lease Agreements, Lessor [Member]      
Lessor, Lease, Description [Line Items]      
Lessor, Operating Lease, Term of Contract 20 years    
Minimum      
Lessor, Lease, Description [Line Items]      
Lessor, Operating Lease, Renewal Term 1 year    
Minimum | Lease Agreements, Lessor [Member]      
Lessor, Lease, Description [Line Items]      
Lessor, Operating Lease, Term of Contract 1 year    
[1] This amount does not include the unguaranteed residual assets
[2] The related-party balance is presented in Noncurrent assets - related parties and the third-party balance is presented in Other noncurrent assets in the Consolidated Balance Sheets.
[3] The related-party balance is presented in Current assets - related parties and the third-party balance is presented in Receivables, net in the Consolidated Balance Sheets.
v3.25.4
Commitments and Contingencies (Detail) - USD ($)
$ in Millions
 1 Months Ended
Dec. 15, 2020
Jul. 31, 2020
Dec. 31, 2025
Dec. 31, 2024
Commitments And Contingencies [Line Items]        
Accrual for environmental loss contingencies     $ 21 $ 15
Environmental Loss Contingency, Statement of Financial Position [Extensible Enumeration]     Other Liabilities, Current, Other Long-term Liabilities Other Liabilities, Current, Other Long-term Liabilities
Loss Contingency, Damages Sought, Value   $ 187    
Loss Contingency, Damages Paid, Value $ 4      
Capital Addition Purchase Commitments        
Commitments And Contingencies [Line Items]        
Contractual commitments to acquire property, plant and equipment     $ 311  
Indirect Ownership Interest | Bakken Pipeline System | Crude Oil and Products Logistics [Member]        
Commitments And Contingencies [Line Items]        
Equity Method Investment, Ownership Percentage     9.19%  
Financial Guarantee | Bakken Pipeline System | Guarantee of Indebtedness of Others        
Commitments And Contingencies [Line Items]        
Guarantor Obligations, Maximum Exposure, Undiscounted     $ 78  
Performance Guarantee | WPC Parent, LLC        
Commitments And Contingencies [Line Items]        
Guarantor Obligations, Maximum Exposure, Undiscounted     $ 109  
v3.25.4
Commitments and Contingencies (Minimum Future Payments) (Details) - Minimum Committed Volume Contracts [Member]
$ in Millions
 12 Months Ended
Dec. 31, 2025
USD ($)
Other Commitments [Line Items]  
2026 $ 163
2027 146
2028 132
2029 46
2030 12
2031 and thereafter 10
Total $ 509
Minimum  
Other Commitments [Line Items]  
Term Of Agreements 1 year
Maximum  
Other Commitments [Line Items]  
Term Of Agreements 7 years
v3.25.4
Subsequent Events (Details) - Senior Notes - USD ($)
$ in Millions
Mar. 01, 2026
Feb. 12, 2026
May 20, 2024
Dec. 31, 2025
Aug. 11, 2025
Dec. 31, 2024
Subsequent Event [Line Items]            
Debt Instrument, Face Amount         $ 4,500  
Senior Note Due June 2034            
Subsequent Event [Line Items]            
Debt Instrument, Issuance Date     May 20, 2024      
Debt Instrument, Face Amount     $ 1,650      
Interest rate, stated percentage     5.50%      
Percent of par     98.778%      
Senior Note Due June 2034 | MPLX LP [Member]            
Subsequent Event [Line Items]            
Interest rate, stated percentage       5.50%    
Long-term debt, gross       $ 1,650   $ 1,650
Senior Notes Due March 2026 [Member] | MPLX LP [Member]            
Subsequent Event [Line Items]            
Interest rate, stated percentage       1.75%    
Long-term debt, gross       $ 1,500   $ 1,500
Subsequent Event | Senior Notes Due April 2036            
Subsequent Event [Line Items]            
Debt Instrument, Issuance Date   Feb. 12, 2026        
Debt Instrument, Face Amount   $ 1,000        
Interest rate, stated percentage   5.30%        
Percent of par   99.678%        
Subsequent Event | Senior Notes Due April 2056            
Subsequent Event [Line Items]            
Debt Instrument, Issuance Date   Feb. 12, 2026        
Debt Instrument, Face Amount   $ 500        
Interest rate, stated percentage   6.10%        
Percent of par   98.453%        
Subsequent Event | Senior Notes Due March 2026 [Member] | MPLX LP [Member]            
Subsequent Event [Line Items]            
Interest rate, stated percentage 1.75%          
Repayments of Debt $ 1,500