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~~March 3120, 2026

HERITAGE FINANCIAL CORPORATION

(Exact name of registrant as specified in its charter)

Commission File Number 000-29480

Washington

91-1857900

(State or other jurisdiction of
incorporation or organization)

(I.R.S. Employer
Identification No.)

201 Fifth Avenue SW,

Olympia

98501

(Address of principal executive offices)

(Zip Code)

(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:


☐			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 each exchange on which registered
Common stock, no par value	HFWA	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 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 28.01 ~~Completion~~Other ~~of Acquisition or Disposition of Assets~~Events

On ~~January~~or 31about March 2, 2026, Heritage Financial Corporation, ~~a Washington corporation~~ (the “Company”), ~~completed~~detected ~~its~~a ~~previously~~cybersecurity ~~announced~~incident ~~acquisition~~involving ~~(the~~an ~~“Merger”)~~internal offile ~~Olympic~~share ~~Bancorp,~~server ~~Inc.~~used ~~(“Olympic”),~~by ~~pursuant~~employees ~~to the Agreement~~ and ~~Plan of Merger, dated September 25, 2025 (~~the ~~“Merger~~exfiltration ~~Agreement”). At the effective time~~ of ~~the~~files ~~Merger~~from onthat ~~January~~file ~~31,~~share ~~2026~~server ~~(the~~which ~~“Effective~~may ~~Time”),~~contain ~~Olympic~~personal ~~merged with and into the Company, with the Company surviving the Merger~~information. ~~Immediately~~The ~~following the Merger, Kitsap~~ Bank,’s acustomer ~~commercial bank headquartered in Port Orchard~~accounts, ~~Washington,~~customer ~~and~~systems ~~a wholly-owned subsidiary of Olympic, merged with~~ and ~~into~~operations ~~Heritage~~were ~~Bank~~not ~~(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~~impacted.

~~Pursuant~~Promptly tofollowing detection, the ~~terms~~Company ofinitiated ~~the~~its ~~Merger~~security ~~Agreement,~~incident asresponse ofplan and began deploying measures to stop the ~~Effective~~unauthorized ~~Time~~activity, ~~each~~including ~~outstanding~~taking ~~share~~the ofaffected ~~Olympic~~system ~~cap~~offline. ~~stock~~The ~~was~~incident ~~automatically~~did ~~converted~~not ascause aany ~~result~~disruptions ofin the ~~Merger~~Company’s ~~into~~operations, ~~the~~which ~~right~~have tocontinued ~~receive~~throughout ~~45.0~~this ~~shares~~time ofin the ordinary course. The Company’s ~~common~~has ~~stock~~launched a thorough investigation and engaged experienced external advisors, ~~with~~including ~~cash~~an toindependent beforensic ~~paid~~investigation infirm ~~lieu~~and oflegal ~~fractional~~counsel, ~~shares.~~to ~~Each~~assess, ~~outstanding~~contain, ~~share~~and ofremediate the incident. The Company’s ~~common~~also ~~stock~~promptly ~~remains~~notified ~~outstanding~~its ~~and~~banking ~~was~~regulators, ~~unaffected~~law byenforcement ~~the~~and ~~Merger~~cyber insurance carrier.

~~The~~While ~~foregoing~~the ~~description~~investigation is ongoing, as of the ~~transactions~~date ~~contemplated~~of bythis filing, the ~~Merger~~Company ~~Agreement~~has ~~does~~ not ~~purport~~determined tothat bethe ~~complete~~cyber ~~and~~incident is ~~qualified~~material inor ~~its~~that ~~entirety~~it byhas ~~reference~~had, toor ~~the~~is ~~full~~reasonably ~~text~~likely ofto ~~the Merger Agreement~~have, ~~attached~~a asmaterial ~~Exhibit~~impact ~~2.1~~on to the Company’s ~~Current~~financial ~~Report~~condition onor ~~Form~~results ~~8-K~~of ~~filed with the Securities and Exchange Commission (the “SEC”) on September 25, 2025, and incorporated herein by reference~~operations.

~~Item~~Forward-Looking ~~7.01 Regulation FD Disclosure~~Statements

OnStatements ~~February~~made 2in this Form 8-K that look forward in time or that express management’s beliefs, ~~2026~~expectations, or hopes are forward-looking statements within the ~~Company~~meaning ~~issued~~of athe ~~press~~Private ~~release~~Securities ~~announcing~~Litigation Reform Act of 1995, as amended. Such forward-looking statements reflect the ~~completion~~views of management at the ~~Merger~~time such statements are made. AThese ~~copy~~statements include, but are not limited to, those regarding actions being taken and that will be taken in response to the cyber incident, expectations regarding insurance coverage, and our assessments of the ~~press~~likely ~~release~~financial and operational impacts of the incident. Responding to and assessing these types of cyber incidents is ~~attached~~inherently challenging and these forward-looking statements are subject to ~~this~~a ~~report~~number asof ~~Exhibit~~risks, ~~99.1~~uncertainties, estimates, and assumptions that may cause actual results to differ materially from current expectations, many of which isare ~~incorporated~~out ~~herein~~of byour ~~reference~~control. As a result, the financial and operational impact of the incident may be more severe than currently anticipated. Risks and uncertainties also include the risk factors detailed in our Securities and Exchange Commission filings, including our Form 10-K for the year ended December 31, 2025. The Company does not undertake to update its forward-looking statements, whether as a result of new information, future events, or otherwise.

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

Exhibit 10.1						Agreement and Plan of Merger, by and between Heritage Financial Corporation and Olympic Bancorp, Inc., dated September 25, 2025* (incorporated herein by reference to Exhibit 2.1 on Form 8-K filed on September 25, 2025).
Exhibit 99.1						Press Release of Heritage Financial Corporation dated February 2, 2026
Exhibit 104						Cover Page Interactive Data File (embedded within the Inline XBRL document)



Exhibit 104						Cover Page Interactive Data File (embedded within the Inline XBRL document)

* 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.

						HERITAGE FINANCIAL CORPORATION
Date:
February 2, 2026						/S/ Bryan D. McDonald
March 20, 2026						/S/ Bryan D. McDonald
						Bryan D. McDonald
						President and Chief Executive Officer

Filing Compare · HERITAGE FINANCIAL CORP /WA/