FORM 3
        
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

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Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940
                      

1. Name and Address of Reporting Person *

Mack-Askew Tracy		 2. Date of Event Requiring Statement (MM/DD/YYYY)
1/1/2021 

 3. Issuer Name and Ticker or Trading Symbol

COLUMBIA BANKING SYSTEM, INC. [COLB]
(Last)        (First)        (Middle)

1301 A STREET, SUITE 800		 4. Relationship of Reporting Person(s) to Issuer (Check all applicable)

__X__ Director                          _____ 10% Owner
_____ Officer (give title below)        _____ Other (specify below)
(Street)

TACOMA, WA 98402      

(City)              (State)              (Zip)
5. If Amendment, Date Original Filed(MM/DD/YYYY)
 

6. Individual or Joint/Group Filing(Check Applicable Line)

_X_ Form filed by One Reporting Person
___ Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Beneficially Owned
1.Title of Security
(Instr. 4)		2. Amount of Securities Beneficially Owned
(Instr. 4)		3. Ownership Form: Direct (D) or Indirect (I)
(Instr. 5)		4. Nature of Indirect Beneficial Ownership
(Instr. 5)

Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivate Security
(Instr. 4)		2. Date Exercisable and Expiration Date
(MM/DD/YYYY)		3. Title and Amount of Securities Underlying Derivative Security
(Instr. 4)		4. Conversion or Exercise Price of Derivative Security5. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 5)		6. Nature of Indirect Beneficial Ownership
(Instr. 5)
Date ExercisableExpiration DateTitleAmount or Number of Shares
Explanation of Responses:

Remarks:
No securities are beneficially owned.
No securities are beneficially owned.
Reporting Owners
Reporting Owner Name / Address
Relationships
Director10% OwnerOfficerOther
Mack-Askew Tracy
1301 A STREET, SUITE 800
TACOMA, WA 98402		X
Signatures
/s/ Cathleen Dent, attorney-in-fact1/4/2021
**Signature of Reporting PersonDate
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
*If the form is filed by more than one reporting person, see Instruction 5(b)(v).
**Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note:File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
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POWER OF ATTORNEY / CONFORMING STATEMENT



    This Statement confirms that the undersigned, has authorized and designated Kumi Y. Baruffi, Cathleen Dent, Karina Busch, Gabrielle Pierce and Laura Moravec each with the full power to act alone, to execute and file on the undersigned's behalf, all Form's 3, 4 and 5 (including any amendments thereto) that the undersigned may be required to file with the U. S. Securities and Exchange Commission as a result of the undersigned's ownership of or transactions in securities of Columbia Banking System, Inc.  The authority of Kumi Y. Baruffi, Cathleen Dent, Karina Busch, Gabrielle Pierce and Laura Moravec under this Statement shall continue until the undersigned is no longer required to file Forms 3, 4 and 5 with regard to his/her ownership of or transactions in securities of Columbia Banking System, Inc., unless earlier revoked in writing.  The undersigned acknowledges that none of Columbia Banking System, Inc., Kumi Y. Baruffi, Cathleen Dent, Karina Busch, Gabrielle Pierce and Laura Moravec is assuming any of the undersigned's responsibilities to comply with Section 16 of the Securities and Exchange Act of 1934.

The Power of Attorney shall remain in full force and effect until the undersigned is no longer subject to the reporting requirements of the Securities Exchange Act of 1934 and the rules thereunder, unless earlier revoked by the undersigned in a signed writing delivered to the attorney-in-fact.

IN WITNESS WHEREOF, the undersigned has caused this Power of Attorney to be executed as of 12/21/2020.

                        Signature: Tracy L Mack-Askew

                        Name: Tracy Mack-Askew