8-K

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 and Exchange Act of 1934

Date of Report (Dated of earliest event reported): December 19, 2025

HERITAGE FINANCIAL CORPORATION

(Exact name of registrant as specified in its charter)

Commission File Number 000-29480

(360) 943-1500

(Registrant’s telephone number, including area code)

Not applicable

(Former name or former address, if changed since last report)

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:

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

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1934 (§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

(d)    Appointment of New Director

On December 18, 2025, the Board of Directors (the “Board”) of Heritage Financial Corporation (“Heritage”), upon the recommendation of the Governance and Nominating Committee of the Board, approved the appointment of Scott T. Allan, age 60, to the Board, effective January 1, 2026. In addition, Mr. Allan was appointed to the Board of Directors of Heritage’s wholly-owned banking subsidiary, Heritage Bank, effective January 1, 2026. Mr. Allan will serve on the Audit and Risk and Technology Committees of the Board. The Board has determined that Mr. Allan is an independent director under the applicable listing standards of the Nasdaq Stock Market.

For further information concerning Mr. Allan’s background, reference is made to the press release dated December 19, 2025, which is attached hereto as Exhibit 99.1 and incorporated herein by reference.

There are no family relationships between Mr. Allan and any director or other executive officer of Heritage or its subsidiaries and Mr. Allan was not appointed as a director pursuant to any arrangement or understanding with any person. Mr. Allan has not engaged in any transactions with Heritage or its subsidiaries that would be reportable as related party transactions under the rules of the Securities and Exchange Commission (the “SEC”).

Mr. Allan will participate in Heritage’s standard non-employee director compensation arrangements, as described under “Director Compensation” in Heritage’s definitive proxy statement filed with the SEC on March 21, 2025, which description is incorporated herein by reference, as such arrangements may be amended from time to time.

Item 9.01 Financial Statements and Exhibits

(d) Exhibits

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.

Document

Exhibit 99.1

For Immediate Release

December 19, 2025

Heritage Financial Corporation Appoints Scott T. Allan

to its Board of Directors

Olympia, WA, December 19, 2025/ PRNewswire / – Heritage Financial Corporation (“Heritage”) (Nasdaq: HFWA) is pleased to announce the appointment of Scott T. Allan to its Board of Directors. Mr. Allan was also appointed to the Board of Directors of Heritage’s wholly-owned subsidiary, Heritage Bank. Both appointments will become effective January 1, 2026.

“We are pleased to welcome Scott to our board of directors in January,” said Brian L. Vance, Board Chair. “Scott is an experienced business leader and board member with a diverse background spanning engineering, consulting, venture-backed startups, and consumer brand leadership.”

“I’m honored to join the Heritage and Heritage Bank Board of Directors and excited to support an organization that is deeply committed to the communities it serves,” said Mr. Allan. “Heritage’s focus on relationship-driven banking and long-term business growth aligns strongly with my own values. I look forward to contributing my experience and collaborating with the board and leadership team to help advance the bank’s strategic priorities.”

Mr. Allan is a partner of Cascade Growth Partners, providing advisory services to founders, CEO’s and executives. Previously, he served as senior vice president and general manager at Helen of Troy from 2016 to 2020. Prior to Helen of Troy’s acquisition of Hydro Flask, he was the president and Chief Executive Officer (“CEO”) of Hydro Flask from 2012 to 2016. Mr. Allan has held a wide array of impactful roles including the following: a sales engineer at CAD Microsystems, a management consultant at PwC, vice president of product operations at iSign Solutions Inc., vice president of product marketing and COO at @pos, general manager at Symbol Technologies, CEO of TriniTEQ, senior director at NXP Semiconductors, and interim CEO at Puffin Drinkwear.

Mr. Allan earned a Bachelor of Science in Mechanical Engineering from the University of California, Berkeley and a Master of Business Administration from the Kellogg School of Management at Northwestern University. Mr. Allan resides in Bend, Oregon and currently serves as an advisory board member of Roam Water, a board member of Rumpl, and an advisory board member for the Oregon State University Cascades. He formerly served as a board member for Camber Outdoors, Cubii, Lotus Sustainables, and Cairn.

About Heritage

Heritage Financial Corporation is an Olympia-based bank holding company with Heritage Bank, a full-service commercial bank, as its sole wholly-owned banking subsidiary. Heritage Bank has a branching network of 51 banking offices in Washington and Oregon. Heritage Bank also does business under the Whidbey Island Bank name on Whidbey Island. Heritage’s stock is traded on the NASDAQ Global Select Market under the symbol “HFWA.” More information about Heritage Financial Corporation can be found on its website at www.hf-wa.com and more information about Heritage Bank can be found on its website at www.heritagebanknw.com.

Contact

Bryan D. McDonald, President and Chief Executive Officer, (360) 943-1500