HERITAGE FINANCIAL CORP /WA/

During the fiscal quarter ended December 31, 2025, none of the Company’s directors or executive officers adopted or terminated any contract, instruction or written plan for the purchase or sale of Company securities that was intended to satisfy the affirmative defense conditions of Rule 10b5-1(c) or any “non-Rule 10b5-1 trading arrangement.

Split Dollar Agreement. On February 25, 2026, Heritage Bank (the “Bank”), the wholly owned subsidiary of Heritage Financial Corporation, entered into a 2026 Endorsement Method Split Dollar Agreement (the “Split Dollar Agreement”) with Nicholas M. Bley. The Split Dollar Agreement provides for the payment of a death benefit to a beneficiary (or beneficiaries) designated by Mr. Bley in an amount up to 100% of his base salary upon the death of Mr. Bley prior to a separation from service and an accelerated benefit of an indeterminable amount (but no more than $500,000) in the event of a chronic or terminal illness prior to separation from service or following a qualifying separation from service.

The foregoing description of the Split Dollar Agreement is qualified in its entirety by reference to the full text of the Form of Heritage Bank 2026 Endorsement Method Split Dollar Agreement, which is filed as Exhibit 10.40 hereto.