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): January 31, 2026

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 2.01 Completion of Acquisition or Disposition of Assets

On January 31, 2026, Heritage Financial Corporation, a Washington corporation (the “Company”), completed its previously announced acquisition (the “Merger”) of Olympic Bancorp, Inc. (“Olympic”), pursuant to the Agreement and Plan of Merger, dated September 25, 2025 (the “Merger Agreement”). At the effective time of the Merger on January 31, 2026 (the “Effective Time”), Olympic merged with and into the Company, with the Company surviving the Merger. Immediately following the Merger, Kitsap Bank, a commercial bank headquartered in Port Orchard, Washington, and a wholly-owned subsidiary of Olympic, merged with and into Heritage Bank (the “Bank”), a commercial bank headquartered in Olympia, Washington, and a wholly-owned subsidiary of the Company, with the Bank continuing as the surviving bank.

Pursuant to the terms of the Merger Agreement, as of the Effective Time, each outstanding share of Olympic cap stock was automatically converted as a result of the Merger into the right to receive 45.0 shares of the Company’s common stock, with cash to be paid in lieu of fractional shares. Each outstanding share of the Company’s common stock remains outstanding and was unaffected by the Merger.

The foregoing description of the transactions contemplated by the Merger Agreement does not purport to be complete and is qualified in its entirety by reference to the full text of the Merger Agreement, attached as Exhibit 2.1 to the Company’s Current Report on Form 8-K filed with the Securities and Exchange Commission (the “SEC”) on September 25, 2025, and incorporated herein by reference.

Item 7.01 Regulation FD Disclosure

On February 2, 2026, the Company issued a press release announcing the completion of the Merger. A copy of the press release is attached to this report as Exhibit 99.1, which is incorporated herein by reference.

The information furnished pursuant to this Item and the related exhibit are being “furnished” and will not, except to the extent required by applicable law or regulation, be deemed “filed” by the Company for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or incorporated by reference in any filing under the Securities Act of 1933, as amended, or the Exchange Act, except as may be expressly set forth by specific reference in such filing.

Item 9.01 Financial Statements and Exhibits

(a) Financial statements of business acquired.

The financial statements required by this Item 9.01(a) will be filed by an amendment to this Current Report on Form 8-K no later than 71 days after the date on which this Current Report on Form 8-K is required to be filed.

(b) Pro forma financial information.

The unaudited pro forma financial statements required by this Item 9.01(b) will be filed by an amendment to this Current Report on Form 8-K no later than 71 days after the date on which this Current Report on Form 8-K is required to be filed.

(d) Exhibits

* The Company has omitted schedules and similar attachments to the subject agreement pursuant to Item 601(b) of Regulation S-K. The Company will furnish a copy of any omitted schedule or similar attachment to the SEC upon request.

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

Heritage Financial Corporation Announces Completion of Acquisition of Olympic Bancorp, Inc.

Olympia, WA, February 2, 2026/ PRNewswire – Heritage Financial Corporation (“Heritage”) (Nasdaq: HFWA) announced that effective January 31, 2026, it completed its previously announced merger (the “Merger”) of Olympic Bancorp, Inc. (“Olympic”) with and into Heritage, and the merger of Kitsap Bank with and into Heritage Bank.

“We welcome Kitsap Bank’s customers and employees to Heritage Bank and look forward to continuing to provide them with excellent service and high quality products,” said Bryan McDonald, Heritage President and CEO.

Heritage will issue an aggregate of approximately 7,167,600 shares of its common stock as consideration in the transaction. Under the terms of the merger agreement, shareholders of Olympic immediately prior to the Merger will receive 45.0 shares of Heritage’s common stock, with cash to be paid in lieu of any fractional shares, for each share of Olympic capital stock. Olympic shareholders will receive information shortly on how to exchange their Olympic shares for Heritage shares.

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 in Washington, Oregon, and Idaho. Heritage Bank also does business under the Whidbey Island Bank name on Whidbey Island and the Kitsap Bank name for branches acquired in the Merger. 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

Cautionary Note Regarding Forward-Looking Statements

This press release includes “forward-looking statements” within the meaning of the Private Securities Litigation Reform Act of 1995. Such statements often include words such as “believes,” “expects,” “anticipates,” “estimates,” “forecasts,” “intends,” “plans,” “targets,” “potentially,” “probably,” “projects,” “outlook” or similar expressions or future or conditional verbs such as “may,” “will,” “should,” “would,” and “could,” as well as the negative of such words. Forward-looking statements are not historical facts but instead represent management's current expectations and forecasts regarding future events, many of which are inherently uncertain and outside of our control. Actual results may differ, possibly materially, from those currently expected or projected in these forward-looking statements. In addition to factors disclosed in reports filed by Heritage with the Securities and Exchange Commission (the "SEC"), risks and uncertainties for Heritage, Olympic and the combined company that may cause actual results or outcomes to differ materially from those anticipated include, but are not limited to: (1) the possibility that any of the anticipated benefits of the Merger will not be realized or will not be realized within the expected time period; (2) the risk that integration of Olympic’s operations with those of Heritage will be materially delayed or will be more costly or difficult than expected; (3) the challenges of integrating and retaining key employees from Olympic; (4) the dilution caused by Heritage’s issuance of additional shares of Heritage’s common stock in connection with the Merger; and (5) changes in the global economy and financial market conditions and the business, results of operations and financial condition of Heritage. Please refer to Heritage’s Annual Report on Form 10-K for the year ended December 31, 2024, as well as Heritage’s other filings with the SEC, for a more detailed discussion of risks, uncertainties and factors that could cause actual results to differ from those discussed in the forward-looking statements.

Any forward-looking statement included in this press release are based only on information currently available to management and speaks only as of the date on which it is made. Heritage undertakes no obligation to publicly update any forward-looking statement, whether written or oral, that may be made from time to time, whether as a result of new information, future developments or otherwise.