Cover Notes to Financial Statements

Cover	12 Months Ended
Cover	Dec. 31, 2025
Document Information [Line Items]
Document Type	DEF 14A
Amendment Flag	false
Entity Information [Line Items]
Entity Registrant Name	ARTHUR J. GALLAGHER & CO.
Entity Central Index Key	0000354190

Pay vs Performance Disclosure

12 Months Ended

Dec. 31, 2025

USD ($)

Dec. 31, 2024

USD ($)

Dec. 31, 2023

USD ($)

Dec. 31, 2022

USD ($)

Dec. 31, 2021

USD ($)

Pay vs Performance Disclosure

Pay vs Performance Disclosure, Table



					Average Summary Compensation Table Total for Non-PEO Named Executive Officers(3)		Average Compensation Actually Paid to Non-PEO Named Executive Officers(4)		Value of Initial Fixed $100 Investment Based On:
Year	Summary Compensation Table Total for PEO(1)		Compensation Actually Paid to PEO(2)						Total Shareholder Return(5)	Peer Group Total Shareholder Return(6)		Net Income (millions)		Adjusted EBITDAC Growth(7)
2025		$20,745,060		$31,447,358		$9,062,499		$10,288,104	$91.98		$93.06		$1,494	25.7%
2024		$17,449,042		$49,400,344		$6,559,832		$13,478,516	$127.35		$122.29		$1,470	20.7%
2023		$15,496,222		$32,997,722		$5,408,851		$9,743,063	$120.50		$108.60		$966	19.0%
2022		$14,194,926		$23,190,737		$4,953,048		$6,908,560	$112.43		$97.54		$1,116	18.4%
2021		$13,882,255		$36,172,141		$5,079,153		$11,580,235	$139.01		$141.53		$955	17.2%

Company Selected Measure Name

Adjusted EBITDAC” growth

Named Executive Officers, Footnote

The dollar amounts reported in this column are the amounts reported for Pat Gallagher (the company’s Chairman and Chief Executive Officer) for

each of the corresponding years in the “Total” column of the Summary Compensation Table.

The dollar amounts reported in this column represent the average of the amounts reported for the company’s named executive officers as a group

(excluding Pat Gallagher) in the “Total” column of the Summary Compensation Table in each applicable year. The named executive officers

included for these purposes in each applicable year 2021 through 2023 are: Doug Howell, Tom Gallagher, Scott Hudson and Walt Bay. With respect

to year 2024 and 2025, the named executive officers included for these purposes are: Doug Howell, Tom Gallagher, Patrick Gallagher and

Walt Bay

Peer Group Issuers, Footnote

Includes Aon plc; Marsh & McLennan Companies, Inc.; Willis Towers Watson plc; and Brown & Brown, Inc.

PEO Total Compensation Amount

$ 20,745,060

$ 17,449,042

$ 15,496,222

$ 14,194,926

$ 13,882,255

PEO Actually Paid Compensation Amount

$ 31,447,358

49,400,344

32,997,722

23,190,737

36,172,141

Adjustment To PEO Compensation, Footnote

(2)The dollar amounts reported in this column represent the amount of “compensation actually paid” to Pat Gallagher, as computed in accordance with

Item 402(v) of Regulation S-K and do not reflect total compensation actually realized or received. In accordance with these rules, these amounts

reflect “Total Compensation” as set forth in the Summary Compensation Table for each year, adjusted as shown below. Equity values are calculated

in accordance with FASB ASC Topic 718, and the valuation assumptions used to calculate fair values did not materially differ from those disclosed

at the time of grant.



Compensation Actually Paid to PEO	2025	2024	2023	2022	2021
Summary Compensation Table Total	$20,745,060	$17,449,042	$15,496,222	$14,194,926	$13,882,255
Less, value of “Stock Awards” and “Option Awards” reported in Summary Compensation Table	$8,812,895	$6,862,620	$5,377,616	$4,802,893	$5,492,149
Less, Change in Pension Value reported in Summary Compensation Table	$194,116	$455	36,498	$—	$19,063
Plus, year-end fair value of outstanding and unvested equity awards granted in the year	$8,911,243	$11,298,539	$11,639,809	$7,503,151	$13,095,137
Plus, fair value as of vesting date of equity awards granted and vested in the year	—	—	—	—	—
Plus (less), year over year change in fair value of outstanding and unvested equity awards granted in prior years	$6,388,426	$24,046,820	$12,000,551	$7,566,230	$14,263,150
Plus (less), year over year change in fair value of equity awards granted in prior years that vested in the year	$4,380,326	$3,435,413	$(762,443)	$(1,297,632)	$416,987
Plus, dividends or other earnings paid on awards in the covered fiscal year prior to vesting if not otherwise included in the Summary Compensation Table Total for the covered fiscal year	$29,315	$33,605	$37,697	$26,954	$25,824
Less, prior year-end fair value for any equity awards forfeited in the year	—	—	—	—	—
Plus, pension service cost for services rendered during the year	—	—	—	—	—
Compensation Actually Paid to Pat Gallagher	$31,447,358	$49,400,344	$32,997,722	$23,190,737	$36,172,141

Non-PEO NEO Average Total Compensation Amount

$ 9,062,499

6,559,832

5,408,851

4,953,048

5,079,153

Non-PEO NEO Average Compensation Actually Paid Amount

$ 10,288,104

13,478,516

9,743,063

6,908,560

11,580,235

Adjustment to Non-PEO NEO Compensation Footnote

The dollar amounts reported in this column represent the average amount of “compensation actually paid” to the named executive officers as a

group (excluding Pat Gallagher), as computed in accordance with Item 402(v) of Regulation S-K. In accordance with these rules, these amounts

reflect “Total Compensation” as set forth in the Summary Compensation Table for each year, adjusted as shown below. Equity values are calculated

in accordance with FASB ASC Topic 718, and the valuation assumptions used to calculate fair values did not materially differ from those disclosed

at the time of the grant.



Average Compensation Actually Paid to Non-PEO Named Executive Officers	2025	2024	2023	2022	2021
Summary Compensation Table Total	$9,062,499	$6,559,832	$5,408,851	$4,953,048	$5,079,153
Less, value of “Stock Awards” and “Option Awards” reported in Summary Compensation Table	$3,160,005	$2,013,638	$1,235,470	$1,109,940	$1,322,515
Less, Change in Pension Value reported in Summary Compensation Table	$22,539	$3	7,164	$—	$48
Plus, year-end fair value of outstanding and unvested equity awards granted in the year	$2,549,271	$2,850,887	$2,387,352	$1,578,828	$2,958,220
Plus, fair value as of vesting date of equity awards granted and vested in the year	—	—	—	—	—
Plus (less), year over year change in fair value of outstanding and unvested equity awards granted in prior years	$771,965	$5,219,967	$3,439,861	$1,941,447	$4,681,938
Plus (less), year over year change in fair value of equity awards granted in prior years that vested in the year	$1,081,636	$855,486	$(258,894)	$(462,939)	$174,571
Plus, dividends or other earnings paid on awards in the covered fiscal year prior to vesting if not otherwise included in the Summary Compensation Table Total for the covered fiscal year	$5,276	$5,985	$8,526	$8,115	$8,916
Less, prior year-end fair value for any equity awards forfeited in the year	—	—	—	—	—
Plus, pension service cost for services rendered during the year	—	—	—	—	—
Average Compensation Actually Paid to Non-PEO Named Executive Officers	$10,288,104	$13,478,516	$9,743,063	$6,908,560	$11,580,235

Compensation Actually Paid vs. Total Shareholder Return

Compensation Actually Paid vs. Net Income

Compensation Actually Paid vs. Company Selected Measure

Total Shareholder Return Vs Peer Group

Tabular List, Table

Most Important Measures in Determining NEO Pay

Adjusted EBITDAC growth

Adjusted Revenue growth

Adjusted EBITDAC per share growth

Total Shareholder Return Amount

$ 91.98

127.35

120.50

112.43

139.01

Peer Group Total Shareholder Return Amount

93.06

122.29

108.60

97.54

141.53

Net Income (Loss), Including Portion Attributable to Noncontrolling Interest

$ 1,494,000,000

$ 1,470,000,000

$ 966,000,000

$ 1,116,000,000

$ 955,000,000

Company Selected Measure Amount

0.257

0.207

0.190

0.184

0.172

PEO Name

Pat Gallagher

Additional 402(v) Disclosure

Total Shareholder Return (TSR) is calculated by dividing (a) the sum of (i) the cumulative amount of dividends for the measurement period,

assuming dividend reinvestment, and (ii) the difference between the company’s share price at the end of each fiscal year shown and the beginning

of the measurement period, by (b) the company’s share price at the beginning of the measurement period. The beginning of the measurement

period for each year in the table is December 31 of the prior fiscal year.

Description of Relationships between Information Presented in Pay versus

Performance Table

As discussed in more detail under Overview of our Executive Compensation Program, an important part of the company’s executive

compensation program is pay-for-performance. While we use several performance measures to align executive compensation with

company performance, not all of those measures are presented in the Pay versus Performance table. We seek to promote the

long-term interests of the company and its stockholders and therefore the performance measures used by the company do not always

correspond directly to compensation actually paid for a particular year (as calculated in accordance with SEC rules). In accordance

with SEC rules, we are providing the following descriptions of the relationships between information presented in the Pay versus

Performance table.

Financial Performance Measures

Adjusted EBITDAC growth is the most important financial performance measure used to link (1) compensation actually paid to the

company’s named executive officers for the most recently completed fiscal year to (2) the company’s performance, although we also

consider adjusted revenue growth and adjusted EBITDAC per share growth in connection with final award determinations for annual

cash incentives and PSU payouts.

The measures used for both long-term and short-term incentive awards have been selected because the Compensation Committee

believes they incentivize our executive officers to make business decisions that align with the long-term interests of our stockholders

and act as effective stewards of our stockholders’ investment. We believe these measures hold our executive officers accountable for

integration expenses associated with our merger and acquisition activity and provide a strong connection between operating decisions

and cash incentives. Further, calculating adjusted EBITDAC growth on a per-share basis to determine PSUs awards encourages

executive officers to be prudent in the use of common stock to finance our merger and acquisition activity.

Measure:: 1

Pay vs Performance Disclosure

Name

Adjusted EBITDAC growth

Non-GAAP Measure Description

“Adjusted EBITDAC” growth as defined for our annual cash incentives and PSUs under Annual Cash Incentives and Long-Term Incentives.

See Exhibit A for reconciliations of non-GAAP measures.

Measure:: 2

Pay vs Performance Disclosure

Name

Adjusted Revenue growth

Measure:: 3

Pay vs Performance Disclosure

Name

Adjusted EBITDAC per share growth

PEO | Aggregate Change in Present Value of Accumulated Benefit for All Pension Plans Reported in Summary Compensation Table

Pay vs Performance Disclosure

Adjustment to Compensation, Amount

$ (194,116)

$ (455)

$ (36,498)

$ 0

$ (19,063)

PEO | Aggregate Pension Adjustments Service Cost

Pay vs Performance Disclosure

Adjustment to Compensation, Amount

PEO | Aggregate Grant Date Fair Value of Equity Award Amounts Reported in Summary Compensation Table

Pay vs Performance Disclosure

Adjustment to Compensation, Amount

(8,812,895)

(6,862,620)

(5,377,616)

(4,802,893)

(5,492,149)

PEO | Year-end Fair Value of Equity Awards Granted in Covered Year that are Outstanding and Unvested

Pay vs Performance Disclosure

Adjustment to Compensation, Amount

8,911,243

11,298,539

11,639,809

7,503,151

13,095,137

PEO | Year-over-Year Change in Fair Value of Equity Awards Granted in Prior Years That are Outstanding and Unvested

Pay vs Performance Disclosure

Adjustment to Compensation, Amount

6,388,426

24,046,820

12,000,551

7,566,230

14,263,150

PEO | Vesting Date Fair Value of Equity Awards Granted and Vested in Covered Year

Pay vs Performance Disclosure

Adjustment to Compensation, Amount

PEO | Change in Fair Value as of Vesting Date of Prior Year Equity Awards Vested in Covered Year

Pay vs Performance Disclosure

Adjustment to Compensation, Amount

4,380,326

3,435,413

(762,443)

(1,297,632)

416,987

PEO | Prior Year End Fair Value of Equity Awards Granted in Any Prior Year that Fail to Meet Applicable Vesting Conditions During Covered Year

Pay vs Performance Disclosure

Adjustment to Compensation, Amount

PEO | Dividends or Other Earnings Paid on Equity Awards not Otherwise Reflected in Total Compensation for Covered Year

Pay vs Performance Disclosure

Adjustment to Compensation, Amount

29,315

33,605

37,697

26,954

25,824

Non-PEO NEO | Aggregate Change in Present Value of Accumulated Benefit for All Pension Plans Reported in Summary Compensation Table

Pay vs Performance Disclosure

Adjustment to Compensation, Amount

(22,539)

(3)

(7,164)

(48)

Non-PEO NEO | Aggregate Pension Adjustments Service Cost

Pay vs Performance Disclosure

Adjustment to Compensation, Amount

Non-PEO NEO | Aggregate Grant Date Fair Value of Equity Award Amounts Reported in Summary Compensation Table

Pay vs Performance Disclosure

Adjustment to Compensation, Amount

(3,160,005)

(2,013,638)

(1,235,470)

(1,109,940)

(1,322,515)

Non-PEO NEO | Year-end Fair Value of Equity Awards Granted in Covered Year that are Outstanding and Unvested

Pay vs Performance Disclosure

Adjustment to Compensation, Amount

2,549,271

2,850,887

2,387,352

1,578,828

2,958,220

Non-PEO NEO | Year-over-Year Change in Fair Value of Equity Awards Granted in Prior Years That are Outstanding and Unvested

Pay vs Performance Disclosure

Adjustment to Compensation, Amount

771,965

5,219,967

3,439,861

1,941,447

4,681,938

Non-PEO NEO | Vesting Date Fair Value of Equity Awards Granted and Vested in Covered Year

Pay vs Performance Disclosure

Adjustment to Compensation, Amount

Non-PEO NEO | Change in Fair Value as of Vesting Date of Prior Year Equity Awards Vested in Covered Year

Pay vs Performance Disclosure

Adjustment to Compensation, Amount

1,081,636

855,486

(258,894)

(462,939)

174,571

Non-PEO NEO | Prior Year End Fair Value of Equity Awards Granted in Any Prior Year that Fail to Meet Applicable Vesting Conditions During Covered Year

Pay vs Performance Disclosure

Adjustment to Compensation, Amount

Non-PEO NEO | Dividends or Other Earnings Paid on Equity Awards not Otherwise Reflected in Total Compensation for Covered Year

Pay vs Performance Disclosure

Adjustment to Compensation, Amount

$ 5,276

$ 5,985

$ 8,526

$ 8,115

$ 8,916

Award Timing Disclosure	12 Months Ended
Award Timing Disclosure	Dec. 31, 2025
Award Timing Disclosures [Line Items]
Award Timing MNPI Disclosure	Equity Award Grant Practices. The Committee has adopted a policy regarding the granting of equity-based awards, including stock options and PSUs granted to named executive officers. Under the policy, annual equity awards are generally granted on March 1 and other equity awards (such as retention, new hire or promotion awards) are granted on predetermined dates intended to be outside of blackout periods under our Insider Trading Policy. However, in limited circumstances, the Board, Committee or General Counsel may approve grants to be effective at other times, including in the event a predetermined date falls within a blackout period. During 2025, we did not time or set the terms of equity awards to take advantage of the release of earnings or take into account other material nonpublic information, and we did not time our disclosure of material nonpublic information to benefit award recipients.
Award Timing Method	Under the policy, annual equity awards are generally granted on March 1 and other equity awards (such as retention, new hire or promotion awards) are granted on predetermined dates intended to be outside of blackout periods under our Insider Trading Policy. However, in limited circumstances, the Board, Committee or General Counsel may approve grants to be effective at other times, including in the event a predetermined date falls within a blackout period.
Award Timing Predetermined	true
Award Timing MNPI Considered	false
Award Timing, How MNPI Considered	During 2025, we did not time or set the terms of equity awards to take advantage of the release of earnings or take into account other material nonpublic information, and we did not time our disclosure of material nonpublic information to benefit award recipients.
MNPI Disclosure Timed for Compensation Value	false

Insider Trading Policies and Procedures	12 Months Ended
Insider Trading Policies and Procedures	Dec. 31, 2025
Insider Trading Policies and Procedures [Line Items]
Insider Trading Policies and Procedures Adopted	true