Form 8-K

8-K — COLUMBIA BANKING SYSTEM, INC.

Accession: 0001193125-26-434182

Filed: 2026-10-27

Period: 2026-10-27

CIK: 0000887343

SIC: 6022 (STATE COMMERCIAL BANKS)

Item: Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers: Compensatory Arrangements of Certain Officers

Item: Financial Statements and Exhibits

Documents

8-K — d20029d8k.htm (Primary)

EX-10.1 (d20029dex101.htm)

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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d)

of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported):

October 27, 2026

Columbia Banking System, Inc.

(Exact name of registrant as specified in its charter)

Washington

000-20288

91-1422237

(State or Other Jurisdiction

of Incorporation)

(Commission

File Number)

(I.R.S. Employer

Identification Number)

1301 A Street

Tacoma, Washington 98402-4200

(Address of Principal Executive Offices) (Zip Code)

(253) 305-1900

(Registrant’s Telephone Number, Including Area Code)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

[☐]

Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

[☐]

Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

[☐]

Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

[☐]

Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

TITLE OF EACH CLASS

TRADING

SYMBOL

NAME OF EXCHANGE

Common Stock

COLB

The Nasdaq Stock Market LLC

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company [☐]

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. [☐]

Item 5.02

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers.

On October 27, 2026, Columbia Banking System, Inc. (the “Company”) and its subsidiary Columbia Bank (the “Bank”) entered into a transition letter (the “Transition Letter”) with Torran Nixon in connection with his transition from his role as Co-President of the Bank and Senior Executive Vice President of the Company (“Bank Co-President”) as of July 1, 2027 or such other mutually agreed date (the “Transition Date”) into a senior advisor role through December 31, 2027 (the “Retirement Date”).

Pursuant to the Transition Letter, during the period he serves as Bank Co-President, Mr. Nixon will be eligible to receive a 2027 equity grant with a target grant date fair value no less than his 2026 grant. While serving as an advisor, Mr. Nixon will continue to be eligible to participate in the Company’s health and welfare benefits, vest in his outstanding equity awards in accordance with their terms and receive salary based on his annual rate as of the Transition Date. Mr. Nixon will be eligible for a payout, if any, under the Company’s annual incentive plan for his service as Bank Co-President during 2027, determined based on actual performance and prorated to reflect his service through the Transition Date.

The foregoing description of the Transition Letter does not purport to be complete and is qualified in its entirety by reference to the full text of the Transition Letter, which is attached hereto as Exhibit 10.1 and incorporated herein by reference.

Item 9.01

Financial Statements and Exhibits.

(d)

EXHIBITS

10.1

Transition Letter, dated October 27, 2026, by and among the Company, the Bank and Mr. Torran Nixon

104

Cover Page Interactive Data File (embedded within the Inline XBRL document)

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

COLUMBIA BANKING SYSTEM, INC.

Date: October 27, 2026

By:

/s/ Kumi Yamamoto Baruffi

Kumi Yamamoto Baruffi

EVP, General Counsel and Corporate Secretary

EX-10.1

Filename: d20029dex101.htm · Sequence: 2

EX-10.1

Exhibit 10.1

October 27, 2026

Tory Nixon

Address on file with the Company

Re:

Leadership Transition

Dear Tory:

This letter memorializes our

understanding regarding your retirement with Columbia Bank (the “Bank”) and your service with Columbia Banking System, Inc. (“CBSI” and together with the Bank, the “Company”).

Transition. You will continue to serve as Co-President of

the Bank and Senior Executive Vice President of CBSI (“Bank Co-President”) through July 1, 2027 or such other mutually agreed date (the “Transition Date”).

During the period in which you serve as Bank Co-President, you shall be eligible to receive a 2027 equity grant (the “2027 Grant”) with a target grant date fair value no less than your 2026

grant. Effective as of the day following the Transition Date, you will (i) begin serving as a senior advisor to the Company (“Advisor”) and (ii) cease serving in any director, officer, manager, committee member or other

positions that you hold with the Company and its subsidiaries (the “Transition”).

You will serve as

Advisor and remain a full-time non-executive employee of the Bank in that role through December 31, 2027 (your termination in accordance with the foregoing, the “Retirement”) or your

earlier termination by the Bank for Cause (as defined in CBSI’s Executive Change in Control and Severance Plan (the “Severance Plan”)).

Advisor Compensation. During the period in which you serve as Advisor, you shall continue to

(i) be eligible to participate in the health and welfare benefit plans maintained by the Company, subject to the terms and conditions thereof, (ii) vest in your outstanding equity awards in accordance with the terms of the applicable plan

and award agreements, and (iii) receive base salary at your annual rate in effect as of the Transition Date, payable in accordance with the Bank’s regular payroll practices. For the avoidance of doubt, you shall be eligible for a payout,

if any, under the Company’s annual incentive plan for your service as Bank Co-President during 2027, determined based on actual performance. Such payout shall be

pro-rated to reflect your service through the Transition Date.

Acknowledgements. You hereby acknowledge that the Transition and the Retirement shall not

constitute “Good Reason” for purposes of any agreement with, or plan maintained by, the Company, including, for the avoidance of doubt, the Severance Plan, the Participation Agreement (as defined below), the 2024 Equity Incentive Plan of

CBSI, and any equity awards granted thereunder. In addition, the Company hereby acknowledges that the Retirement shall constitute a “qualifying retirement” for purposes of your outstanding equity awards (including the 2027 Grant), so

long as Cause does not then exist.

Restrictive Covenants. The restrictive covenants set forth in Section 4(b) (Confidentiality)

of the Severance Plan and Section 2(b) of the Participation Agreement (Non-interference), effective as of March 1, 2025, by and between you and CBSI (the “Participation

Agreement”) will remain in full force and effect pursuant to their terms.

-1-

Non-Disparagement. At all times during your employment with the

Bank and perpetually thereafter, to the fullest extent permitted by law and subject to Section 6 (Whistleblower Protections) below, you agree that you will not make any defamatory or derogatory statements concerning the Company or any of

its affiliates or predecessors and their respective officers, directors or employees, nor will you authorize, encourage or participate with anyone to make such statements.

Whistleblower Protections. Notwithstanding the foregoing, nothing in this letter is intended to, and

Section 5 above will not, (i) preclude you from disclosing or discussing information lawfully acquired about wages, hours or other terms and conditions of employment if used for purposes protected by Section 7 of the National Labor

Relations Act such as joining or forming a union, engaging in collective bargaining or engaging in other concerted activity for the mutual aid or protection of employees; (ii) limit your rights under applicable law to initiate communications

directly with, provide information to, respond to any inquiries from, or report possible violations of law or regulation to any governmental entity or self-regulatory authority, or to file a charge with or participate in an investigation conducted

by any governmental entity or self-regulatory authority, and you do not need the Company’s permission to do so; (iii) require you to notify the Company of a request for information from any governmental entity or self-regulatory authority

that is not directed to the Company or of your decision to file a charge with or participate in an investigation conducted by any governmental entity or self-regulatory authority; (iv) limit or restrict your

non-waivable right to file an administrative complaint with the Equal Employment Opportunity Commission (“EEOC”), the National Labor Relations Board (“NLRB”), or with

another governmental agency; (v) require you to dismiss any pending administrative complaint with the EEOC, NLRB, or with another governmental agency; (vi) limit or restrict your non-waivable right

to participate as a witness or cooperate in any investigation by the EEOC, NLRB, or another governmental agency; or (vii) limit your right to receive any bounty or monetary award from any governmental entity or regulatory or law enforcement

authority in connection with information provided to any governmental entity or other protected “whistleblower” activity (such protected activity, collectively, the “Protected Activity”). The parties acknowledge that

you have the right to: (1) report any good faith allegation of unlawful employment practices to any appropriate federal, state, or local government agency enforcing discrimination laws; (2) report any good faith allegation of criminal

conduct to any appropriate federal, state, or local official; (3) participate in a proceeding with any appropriate federal, state, or local government agency enforcing discrimination laws; (4) make any truthful statements or disclosures

required by law, regulation, or legal process or pursuant to any legal process between you and the Company or any of its affiliates; and (5) request or receive confidential legal advice. Notwithstanding the foregoing, you recognize that, in

connection with the provision of information to any governmental entity or self-regulatory authority, you must inform such governmental entity or self-regulatory authority that the information you are providing is confidential. Despite the

foregoing, you are not permitted to reveal to any third party, including any governmental entity or self-regulatory authority, information you came to learn during your service to the Company that is protected from disclosure by any applicable

privilege, including but not limited to the attorney-client privilege or attorney work product doctrine. The Company does not waive any applicable privileges or the right to continue to protect its privileged attorney-client information, attorney

work product, and other privileged information.

-2-

General Provisions. This letter constitutes the entire agreement of the parties related to the

subject matter hereof. No waiver, amendment, modification or cancellation of any term or condition of this letter will be effective unless executed in writing by each of the Bank, CBSI and you. This letter may be executed in separate counterparts,

each of which is deemed to be an original and all of which taken together constitute one and the same. Section 6(g) (Disputes) and 6(h) (Governing Law) of the Severance Plan will apply to this letter mutatis

mutandis.

* * *

-3-

Sincerely,

Columbia Bank

By:

/s/ Clint Stein

Name: Clint Stein

Title: CEO

Columbia Banking System, Inc.

By:

/s/ Clint Stein

Name: Clint Stein

Title: Chairman, President and CEO

By:

/s/ Torran Nixon

Name: Torran Nixon

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