banr-20260330

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, DC 20549

SCHEDULE 14A INFORMATION

Proxy Statement Pursuant to Section 14(a) of the

Securities Exchange Act of 1934

Filed by the registrant ☒ Filed by a party other than the registrant ☐

Check the appropriate box:

☐ Preliminary proxy statement

☐ Confidential, for use of the Commission only (as permitted by Rule 14a-6(e)(2))

☒ Definitive proxy statement

☐ Definitive additional materials

☐ Soliciting material pursuant to § 240.14a-12

BANNER CORPORATION

(Name of registrant as specified in its charter)

N/A

(Name of person(s) filing proxy statement, if other than the registrant)

Payment of filing fee (Check all boxes that apply):


☒			No fee required.
☐			Fee paid previously with preliminary materials.
☐			Fee computed on table in exhibit required by Item 25(b) per Exchange Act Rules 14a-6(i)(1) and 0-11.

2026

Proxy Statement

Dear Shareholder:

You are cordially invited to attend the annual meeting of shareholders of Banner Corporation, which will be held on Wednesday, May 20, 2026, at 10:00 a.m., Pacific Time. Our 2026 annual meeting of shareholders will be a virtual meeting conducted solely online via live webcast. There is no physical location for the annual meeting. The online meeting format will facilitate remote shareholder attendance and participation, including the ability to vote your shares electronically and submit questions during the meeting.

You can attend the meeting by visiting https://meetnow.global/M4KQTQY. To participate in the annual meeting, registered shareholders will need the control number included on their proxy card and all other shareholders will need to follow the instructions that accompanied their proxy materials.

The Notice of Annual Meeting of Shareholders and Proxy Statement describe the formal business to be transacted at the meeting. Directors and officers of Banner Corporation, as well as a representative of Baker Tilly US, LLP, our independent registered public accounting firm, will be available to respond to shareholder questions. We intend to answer questions pertinent to our business immediately following the formal meeting of shareholders.

It is important that your shares are represented at the meeting, whether or not you attend the meeting virtually and regardless of the number of shares you own. To make sure your shares are represented, we urge you to vote promptly. You may vote your shares via the Internet or a toll-free telephone number, or by completing and mailing your proxy card. If you attend the virtual meeting using your shareholder control number, you may vote your shares at that time even if you have previously submitted your proxy.

We hope you can attend the virtual annual meeting.

Sincerely,

Mark J. Grescovich

President and Chief Executive Officer

April 6, 2026

Notice of Annual Meeting of Shareholders



Date Wednesday, May 20, 2026	Time 10:00 a.m., Pacific Time	Record Date March 12, 2026

Location Online at https://meetnow.global/M4KQTQY

Important notice regarding the availability of proxy materials for the annual meeting of shareholders The accompanying Proxy Statement and proxy card were either made available to you online or mailed to you beginning on or about April 6, 2026. Our Proxy Statement, proxy card and 2025 Annual Report to Shareholders are available at www.bannerbank.com/proxymaterials.

Voting Matters

At or before the 2026 Annual Meeting of Shareholders, we ask that you vote the following items:


Items of Business		Board Recommendation
Proposal 1	Election of twelve directors to each serve for a one-year term.	Vote FOR each director nominee
Proposal 2	Advisory (non-binding) approval of the compensation of our named executive officers as disclosed in this Proxy Statement.	Vote FOR
Proposal 3	Ratification of the Audit Committee’s appointment of Baker Tilly US, LLP as our independent registered public accounting firm for 2026.	Vote FOR
We will also consider and act upon such other matters as may properly come before the meeting or any adjournments or postponements thereof. As of the date of this notice, we are not aware of any other business to come before the annual meeting.

Your Vote is Important — How to Vote

Internet

Go to www.investorvote.com/BANR or scan the QR code on your proxy card

Telephone

Call 1 (800) 652-VOTE (8683) within the USA, US territories and Canada

Mail

Sign, date and mail the proxy card

IMPORTANT: Voting promptly will save us the expense of further requests for proxies in order to ensure a quorum.

To ensure your shares are represented at the meeting, please vote via the Internet or telephone, or sign, date and mail your proxy card. Your proxy is solicited on behalf of the Board of Directors. The proxy will not be used if you attend and vote at the virtual annual meeting. Regardless of the number of shares you own, your vote is very important. Please act today. Our 2026 annual meeting of shareholders will be a virtual meeting conducted solely online via live webcast. The online meeting format facilitates remote shareholder attendance and participation, including the ability to vote shares electronically and submit questions during the meeting. To participate in the annual meeting, registered shareholders will need the control number included on their proxy card and all other shareholders will need to follow the instructions that accompanied their proxy materials. A list of Banner shareholders as of the record date will be available for inspection, via the “Shareholder” login on the virtual meeting website noted above, by any shareholder (or their agents or attorneys) beginning ten days prior to the meeting and continuing through the meeting. Beneficial owners of shares held in street name who wish to participate in the meeting as a “Shareholder” must register with Computershare no later than 5:00 p.m., Eastern Time, on May 14, 2026. (Late submissions may be processed to the extent feasible, but registration cannot be guaranteed in time for participation in the meeting.) To request registration, forward the proxy-granting email from your broker or email an image of your legal proxy to legalproxy@computershare.com, with a subject line of “Legal Proxy,” or mail your request to Computershare, Banner Corporation Legal Proxy, P.O. Box 43001; Providence, RI 02940-3001. Computershare will confirm your registration and provide you with a unique control number which enables full participation in the meeting.

BY ORDER OF THE BOARD OF DIRECTORS

SHERREY LUETJEN

Secretary, Banner Corporation

Walla Walla, Washington

April 6, 2026



Information About the Annual Meeting			1
Security Ownership of Certain Beneficial Owners and Management			2
Proposal 1 – Election of Directors			5
Corporate Governance			15
Directors ’ Compensation			24
Compensation Discussion and Analysis			26
Executive Compensation			40
Pay Versus Performance			49
Proposal 2 – Advisory Vote to Approve Executive Compensation			54

Information A bout O ur Executive Officers			55
Audit Committee Matters			60
Proposal 3 – Ratification of Appointment of Independent Registered Public Accounting Firm			61
Miscellaneous			63
Shareholder Proposals			64
Annual Meeting Frequently Asked Questions			65
Annex: Non-GAAP Reconciliation			69


Name	Number of Shares Beneficially Owned (1)		Percent of Voting Shares Outstanding (%)

Beneficial Owners of More Than 5%
BlackRock, Inc.	4,951,813	(2)	14.62	%
The Vanguard Group	3,816,250	(3)	11.27	%
Dimensional Fund Advisors LP	2,257,929	(4)	6.67	%
State Street Corporation	1,779,867	(5)	5.25	%
Directors
Ellen R.M. Boyer	5,128		*
Connie R. Collingsworth	12,066	(6)	*
Margot J. Copeland	3,747		*
Roberto R. Herencia	15,864		*
John R. Layman	35,365	(7)	*
Monica B. O'Reilly	0		*
John C. Pedersen	6,550		*
Kevin F. Riordan	9,749		*
Terry S. Schwakopf	8,133		*
Judith A. Steiner	1,790		*
Millicent C. Tracey	0		*
Paul J. Walsh	3,747		*
Named Executive Officers
Mark J. Grescovich**	192,432		*
Robert G. Butterfield	10,890		*
James M. Costa	14,822		*
Mark C. Borrecco	4,018		*
Cynthia D. Purcell	31,068		*

All Executive Officers and Directors as a Group (27 persons)	471,184		1.39


The Board of Directors recommends a vote FOR the election of each of the following director nominees.


Name	Age as of December 31, 2025	Year First Elected or Appointed Director	Term to Expire (1)
Board Nominees
Ellen R.M. Boyer	65	2021	2027
Connie R. Collingsworth	67	2013	2027
Margot J. Copeland	74	2022	2027
Mark J. Grescovich	61	2010	2027
Roberto R. Herencia	66	2016	2027
John R. Layman	67	2007	2027
Monica B. O’Reilly	59	2026	2027
John C. Pedersen	68	2021	2027
Kevin F. Riordan	69	2018	2027
Judith A. Steiner	63	2026	2027
Millicent C. Tracey	57	2025	2027
Paul J. Walsh	57	2022	2027


Ellen R.M. Boyer

Director Since: 2021	Committees:
	•Audit •Compensation and Human Capital (Chair)	• Executive
Key Qualifications: •Audit experience; qualifies as an audit committee financial expert •Certified Public Accountant (Active) •Experienced chief financial officer and chief operating officer •Acquisition and strategic planning expertise
Ellen R.M. Boyer has served as Chief Financial Officer for Northwest Center, a nonprofit corporation based in Renton, Washington, since December 2024. Ms. Boyer was previously Chief Financial Officer of Logic20/20, a business and technology consulting firm headquartered in Seattle, Washington, until her retirement in April 2024. Ms. Boyer has over 30 years of finance and operational experience in a variety of industries, including technology, financial services and healthcare. Prior to joining Logic20/20 in 2014, Ms. Boyer held chief financial officer and/or chief operating officer roles at several companies in the Seattle area beginning in 1997. Ms. Boyer was previously an Audit Senior Manager at PriceWaterhouseCoopers, where she worked for 12 years. Ms. Boyer has extensive experience in strategic planning, mergers and acquisitions, governance matters, organizational effectiveness, and audit and financial matters. Ms. Boyer graduated from Oregon State University with degrees in Accounting and Spanish and minors in Computer Science and Latin American Affairs. She maintains an active Certified Professional Accountant license. Ms. Boyer is active in her community and has served on several for-profit and not-for-profit boards, including Umpqua Holdings Corporation (now Columbia Banking System, Inc. (Nasdaq: COLB)) from 2014 through 2016 and Sterling Financial Corporation (subsequently Umpqua and now Columbia) from 2007 through 2014. Ms. Boyer qualifies as an audit committee financial expert. This qualification, together with her deep financial expertise and strategic planning experience, adds value to the Board and the directors believe that Ms. Boyer should continue to serve on the Board of Directors.


Connie R. Collingsworth

Director Since: 2013	Committees:
	•Compensation and Human Capital •Corporate Governance/Nominating (Chair)	•Executive
Key Qualifications: •Risk management expertise •Acquisition, business expansion and complex investment experience •Organizational effectiveness and corporate governance best practices leadership •Unique insights regarding corporate responsibility issues
Connie R. Collingsworth served as the Chief Operating Officer of the Gates Foundation for more than 20 years, scaling its operations throughout the world to distribute its $9B annual budget. Her responsibilities included managing information technology, operations, human resources, legal and security across the enterprise, including its offices located throughout the world. As the chief legal officer of the Gates Foundation, she served as an advisor to the Trustees and its independent board on governance, risk management, regulatory compliance, executive compensation and CEO succession. Prior to joining the Gates Foundation, Ms. Collingsworth was a corporate securities partner at K&L Gates, one of the largest law firms in the world, where her practice focused on leading venture capital, private equity and M&A transactions. Ms. Collingsworth previously served on the Board of Directors and as Chair of the Compensation Committee of Premera Blue Cross, the largest health plan provider in the Pacific Northwest. She currently serves as an advisory board member of Planet First Partners, a European private equity firm, and holds board roles on several nonprofit organizations. Related activities include Affiliate Professor at the University of Washington Foster School of Business teaching Corporate Governance and serving as an Executive Sponsor of Bank of America’s Enterprise Executive Development Program. Ms. Collingsworth was honored as one of WomenInc. magazine’s 2019 Most Influential Corporate Directors. Based on these qualifications, the directors believe that Ms. Collingsworth should continue to serve on the Board of Directors.


Margot J. Copeland

Director Since: 2022			Committees:
			•Compensation and Human Capital •Credit Risk
Key Qualifications: •Extensive banking and executive leadership •Philanthropic and community engagement experience •Corporate responsibility expertise
Margot J. Copeland specializes in developing strategies in the areas of workforce development and management, leadership, diversity and inclusion, philanthropy, and community outreach and engagement. Ms. Copeland has over 20 years of experience, with her previous positions being at KeyBank (a subsidiary of KeyCorp (NYSE: KEY)) and its affiliate, KeyBank Foundation, in Cleveland, Ohio. At KeyBank, she was Executive Vice President and Director Corporate Philanthropy and Community Engagement from 2001 through 2019. During the same period, she served as Board Chair and Chief Executive Officer for KeyBank Foundation. As a corporate officer and leader of corporate philanthropy and civic engagement, Ms. Copeland was a member of KeyBank’s Corporate Social Responsibility Council, which focused on philanthropic investments, corporate citizenship, and regulatory and corporate strategy. She was also a member of the Diversity & Inclusion Council and she served as KeyBank’s Chief Diversity Officer from 2001 through 2013. Prior to joining KeyBank, Ms. Copeland served on the Advisory Board of US Bank (formerly Firstar) from 1998 through 2001. Ms. Copeland is actively involved in her community, having served on a number of advisory boards and boards of directors for educational institutions, health care systems, community organizations and other nonprofit entities. She currently serves on the Board of Trustees for The Cleveland Clinic and the Board of Directors for AARP, among others. Ms. Copeland received a Master’s degree from The Ohio State University, a Bachelor of Science in Physics from Hampton University, Hampton, Virginia and an Honorary Doctorate of Humane Letters from Cuyahoga Community College, Cleveland, Ohio. With her vast experience in social responsibility and her long-tenured connection to banking, the directors believe that Ms. Copeland should continue to serve on the Board of Directors.


Mark J. Grescovich
President and CEO
Director Since: 2010	Committees:
	•Credit Risk •Executive	•Risk
Key Qualifications: •Extensive bank leadership experience •Acquisition and strategic planning expertise •Credit and risk management expertise
Mark J. Grescovich is President and Chief Executive Officer, and a director, of Banner Corporation and Banner Bank. Mr. Grescovich joined Banner Bank in April 2010 and became Chief Executive Officer in August 2010 following an extensive banking career specializing in finance, credit administration and risk management. Under his leadership, Banner has grown from $4.7 billion in assets in 2010 to more than $16 billion through organic growth as well as selective acquisition. During that time, Mr. Grescovich has guided the expansion of Banner’s footprint to over 135 locations in four states. Prior to joining Banner, Mr. Grescovich was the Executive Vice President and Chief Corporate Banking Officer for Akron, Ohio-based FirstMerit Corporation and FirstMerit Bank N.A. He assumed responsibility for FirstMerit’s commercial and regional line of business in 2007, having served since 1994 in various commercial and corporate banking positions, including that of Chief Credit Officer. Prior to joining FirstMerit, Mr. Grescovich was a Managing Partner in corporate finance with Sequoia Financial Group, Inc. of Akron, Ohio, and a commercial and corporate lending officer and credit analyst with Society National Bank of Cleveland, Ohio. He has a Bachelor of Business Administration degree in finance from Miami University and a Master of Business Administration degree, also in finance, from The University of Akron.


Roberto R. Herencia
Board Chair
Director Since: 2016	Committees:
	•Compensation and Human Capital •Corporate Governance/Nominating	•Credit Risk •Executive (Chair)
Key Qualifications: •Extensive bank leadership experience, including as a director and chief executive officer •Acquisition and strategic planning expertise •Credit and risk management expertise
Roberto R. Herencia is President and Chief Executive Officer of BXM Holdings, a fund specializing in community bank investments. He is a director and Chairman of the Board of First BanCorp. (NYSE: FBP) and its subsidiary, FirstBank Puerto Rico, positions he has held since October 2011. He has been an independent director and the Chairman of the Board of Byline Bancorp (NYSE: BY) and its subsidiary bank, Byline Bank, since June 2013, and effective February 12, 2021, he assumed the role of Chief Executive Officer of Byline Bancorp. Between 2009 and 2010, Mr. Herencia was President and Chief Executive Officer of Midwest Banc Holdings, Inc. and its subsidiary, Midwest Bank and Trust. Prior to that, he spent 17 years with Popular Inc. as its Executive Vice President and as President of Popular Inc.’s subsidiary, Banco Popular North America. Prior to joining Popular, Mr. Herencia spent 10 years with The First National Bank of Chicago (now J.P. Morgan Chase) in a variety of roles, including Deputy Senior Credit Officer and Head of the Emerging Markets Division. Mr. Herencia previously served on the US International Development Finance Corporation’s Board of Directors, to which he was appointed by President Obama in 2011. He graduated magna cum laude and received his Bachelor of Science in Business Administration degree in finance from Georgetown University and his Master of Business Administration degree from the Kellogg School of Management at Northwestern University. Based on these qualifications, the directors believe that Mr. Herencia should continue to serve on the Board of Directors.


John R. Layman

Director Since: 2007			Committees:
			•Audit •Risk
Key Qualifications: •Extensive legal experience, including in mergers and acquisitions and complex litigation matters •Bank leadership and operational experience •Risk management expertise •Strategic planning experience
John R. Layman served as Co-Vice Chairman of the Board of Directors of F&M Bank until its acquisition by Banner Bank in May 2007. He is Managing Partner of Layman Law Firm, PLLP, with which he has been associated since 1983. His areas of practice include real estate development, commercial litigation, personal injury and product liability. He also has experience in securities litigation, fiduciary obligations, corporate governance and compliance and reporting requirements. Based on these qualifications, the directors believe that Mr. Layman should continue to serve on the Board of Directors.


Monica B. O’Reilly

Director Since: 2026			Committees:
			•Corporate Governance/Nominating •Risk
Key Qualifications: •Deep expertise in enterprise and operational risk management •Corporate governance best practices and organizational effectiveness expertise •Significant experience in regulatory compliance
Monica B. O’Reilly is a strategic leader who leverages over 30 years of experience helping global financial services companies achieve business results. She is an advisor to Fortune 500 C-suite executives, corporate boards and audit committees on regulatory compliance, enterprise and operational risk management, artificial intelligence and cybersecurity. Ms. O’Reilly was the Vice Chairman and US Financial Services Leader at Deloitte from 2020 to 2025, and served on Deloitte’s Board Council and Strategic Investment Committee in which she oversaw various acquisitions and investments. Under her leadership as Co-Chair for Deloitte’s Nominating Committee, she oversaw CEO and board director selection. Recognized as an industry expert, Ms. O’Reilly has co-authored reports on board governance, the financial marketplace, and risk management. She was named as one of the “Most Influential Women in Business” by the San Francisco Business Journal in 2021. Ms. O’Reilly holds a B.A. in English and Education from Queen’s University Belfast and completed Wharton Business School’s Executive Leadership Program. Ms. O’Reilly’s deep risk management and corporate governance expertise adds value to the Board and the directors believe that Ms. O’Reilly should continue to serve on the Board of Directors.


Kevin F. Riordan

Director Since: 2018	Committees:
	•Audit (Chair) •Compensation and Human Capital	•Credit Risk •Executive
Key Qualifications: •Audit experience; qualifies as an audit committee financial expert •Risk management expertise •Corporate governance best practices and organizational effectiveness expertise
Kevin F. Riordan retired as a Banking & Capital Markets audit and client service Partner of PricewaterhouseCoopers LLP (PwC), a global professional services firm, in June 2014, having served in that capacity since 2000. Prior to joining PwC in 1994, Mr. Riordan served various banking and securities trading companies as both an independent auditor and senior financial/accounting executive. During his career at PwC, Mr. Riordan gained significant experience working with the boards and audit committees of publicly traded banking and lending institutions while managing major client relationships across multiple markets. In those roles, Mr. Riordan developed expertise in complex accounting, auditing and financial reporting matters. He has been a Certified Public Accountant since 1983. Mr. Riordan’s qualification as an audit committee financial expert was the primary reason for his nomination to the Board. The directors believe that this qualification, together with his experience with banking entities and financial reporting matters, support Mr. Riordan’s continued service on the Board of Directors.


Millicent C. Tracey

Director Since: 2025			Committees:
			•Corporate Governance/Nominating •Risk
Key Qualifications: •Extensive banking leadership, including as a director •Payments services, fintech, cybersecurity and technology experience •Advisory board experience
Millicent C. Tracey has more than 20 years of experience in the financial services industry with significant expertise in the areas of banking, payment services, and fintech strategies. She currently serves as a Board Director for Dwolla, Inc., a privately held fintech company. She worked for Wells Fargo Bank, a subsidiary of Wells Fargo & Company (NYSE: WFC), in the San Francisco Bay area for more than 19 years, most recently as Senior Vice President, Payments API Product Manager from 2014 until 2019. She has advised on business-to-business digital payments strategies, innovative technology solutions, product go-to-market launch strategies, regulatory compliance, cybersecurity, fraud, treasury management, and risk mitigation strategies. These skills and experience are highly relevant to Banner’s current business environment, and the directors believe Ms. Tracey should continue to serve on the Board of Directors. Ms. Tracey served on the Board of Directors of California BanCorp (Nasdaq: CALB) and its banking subsidiary, California Bank of Commerce, from 2021 until 2024. She earned a Juris Doctor from Mitchell Hamline School of Law and a Bachelor of Arts from the University of Wisconsin – Madison.


CYBERSECURITY GOVERNANCE PRINCIPLES
•Protect the confidentiality, integrity and availability of Banner data by means of comprehensive security policies, processes and technologies that allow for the proper protection of data and that facilitate secure, robust access •Continually maintain a scalable, secure and reliable production environment by means of advanced security processes and technologies to facilitate comprehensive attack identification, analysis and response •Design and maintain a secure digital environment to protect and enable Banner’s operations by implementing effective and secure technologies •Establish a mutual culture of security by creating a secure environment and a strong alliance with all employees in the practice of information security •Engage external expertise as part of the verification and ongoing testing of an effective cybersecurity program


Activity			Succession Planning Impact
Talent and succession planning			Provides directors with detailed insight on senior management selection, high-potential leaders, succession readiness, and leadership development to build and maintain a pipeline of skilled and capable individuals ready to assume critical roles within the organization
Employee engagement and organizational effectiveness review			Informs the directors as to the current state of Banner’s talent base in terms of employee engagement levels and overall organizational effectiveness
Enterprise-wide human capital risk assessment report			Enables Board oversight of human capital risk and related mitigation efforts regarding talent recruitment, development and retention