The information in this proxy statement/prospectus is not complete and may be changed. We may not issue the securities offered by this proxy statement/prospectus until the registration statement filed with the Securities and Exchange Commission is effective. This document is not an offer to sell these securities, and we are not soliciting an offer to buy these securities, in any jurisdiction where the offer or sale is not permitted.

PRELIMINARY PROXY STATEMENT/PROSPECTUS—SUBJECT TO COMPLETION—

DATED JUNE 29, 2026

To the Shareholders of Pacific West Bancorp:

You are cordially invited to attend the special meeting of shareholders of Pacific West Bancorp, which we refer to as Pacific West. The special meeting will be held in lieu of Pacific West’s annual meeting of shareholders on [•] [•], 2026, at [•], a.m., Pacific Time at Pacific West’s corporate offices, located at 1300 SW Fifth Avenue, Suite 900, Portland, Oregon 97201.

As described in the accompanying proxy statement/prospectus, the board of directors of Pacific West has approved a merger agreement that provides for the merger of Pacific West with and into FS Bancorp, with FS Bancorp being the surviving corporation. We are seeking your vote on this important transaction, as well as any other matters that may be considered at the special meeting.

If the merger is completed, each share of Pacific West common stock outstanding immediately prior to the effective time of the merger will be converted into the right to receive, at the holder’s election, either cash, which we refer to as the cash consideration, or shares of FS Bancorp common stock together with cash in lieu of a fractional share of FS Bancorp common stock, which we refer to as the stock consideration. Shortly after the merger, Pacific West’s wholly owned banking subsidiary, Pacific West Bank, will be merged with and into FS Bancorp’s subsidiary bank, 1st Security Bank of Washington, with 1st Security Bank as the resultant bank. As a Pacific West shareholder, you will have the opportunity to elect the form of consideration to be received for all shares of Pacific West common stock held by you, subject to the allocation and proration procedures set forth in the merger agreement and described in this proxy statement/prospectus. These allocation procedures are intended to allocate the aggregate merger consideration, which consists of $16,832,742 in cash and 430,176 shares of FS Bancorp common stock, among Pacific West’s shareholders in the event of any oversubscription of the cash or stock. The form of the merger consideration ultimately received by you will depend upon these procedures, which are described in this proxy statement/prospectus, and the choices of other Pacific West shareholders and, as a result, may be different from what you elect.

You should obtain current stock quotations for FS Bancorp common shares and Pacific West common shares. FS Bancorp common shares trade on the Nasdaq Capital Market under the symbol “FSBW” and Pacific West common shares are reported on the OTCID Basic Market under the symbol “PWBK.”

The merger agreement provides that the amount of the cash consideration and the amount of stock consideration will be as equal in value at the time of the merger as possible, with shares of FS Bancorp common stock valued utilizing the volume-weighted average trading price of FS Bancorp common stock for the 10 trading days ending on the last trading day immediately preceding the closing date of the merger, which we refer to as the Closing FS Bancorp Share Value. Therefore, the value of the aggregate merger consideration, the amount of the cash consideration per share of Pacific West common stock, and the number of shares of stock consideration per share of Pacific West common stock, will fluctuate between the date of this proxy statement/prospectus and the completion of the merger based upon the market value of FS Bancorp common stock. Based on the Closing FS Bancorp Share Value on Nasdaq of $41.69 for the 10 trading days preceding February 25, 2026, the day the merger agreement was signed, the aggregate merger consideration, including the cash and stock components, was valued at $34,768,250, and if the merger had been completed on that day, the amount of the cash consideration would have been $12.64 per share of Pacific West common stock and the stock consideration would have consisted of 0.3032 shares of FS Bancorp common stock per share of Pacific West common stock. Based on the Closing FS Bancorp Share Value on Nasdaq of $[●] for the 10 trading days preceding [●] [●], 2026, the latest practicable trading day before the date of this proxy statement/prospectus, the aggregate merger consideration was valued at $[●] million and if the merger were completed on that day, the amount of the cash consideration would have been $[●] per share of Pacific West common stock and the stock consideration would have consisted of [●] shares of FS Bancorp common stock per share of Pacific West common stock. You should obtain current market quotations for FS Bancorp’s common stock and consult with your financial and tax advisors before deciding which consideration you elect.

We cannot complete the merger unless the holders of a majority of the outstanding Pacific West common shares vote to approve the merger agreement and as a result, a failure to vote shares in favor of the merger will have the same effect as a vote against the merger. Your vote is therefore very important. Pacific West will hold its special meeting of shareholders on [●] [●], 2026 to vote on the merger agreement and the related transactions. Your board of directors recommends you vote FOR approval of the merger agreement and the other items to be considered at the special meeting. Whether or not you plan to attend the special meeting, please take the time to vote on the proposal to approve the merger agreement and the other matters to be considered by following the instructions that accompany your proxy card and casting your vote by internet, by telephone, or by returning your completed, signed, and dated proxy card in the enclosed envelope (please allow a minimum of 10 days for your proxy card to be processed). Please vote as soon as possible to make sure that your shares are represented at the special meeting. Abstaining or failing to vote will have the same effect as voting against the merger agreement.

We encourage you to read carefully the detailed information about the merger contained in this proxy statement/prospectus, including the section entitled “Risk Factors” beginning on page 14. This proxy statement/prospectus incorporates important business and financial information and risk factors about FS Bancorp that are not included in or delivered with this document. See the section entitled “Where You Can Find More Information” on page 106.

The securities that FS Bancorp is offering through this proxy statement/prospectus are not savings or deposit accounts or other obligations of any bank or nonbank subsidiary of FS Bancorp or Pacific West, and they are not insured by the Federal Deposit Insurance Corporation or any other government agency.

This proxy statement/prospectus is dated [●], [●], 2026 and is first being mailed or otherwise delivered to Pacific West shareholders on or about [●] [●], 2026.

REFERENCES TO ADDITIONAL INFORMATION

This proxy statement/prospectus incorporates important business and financial information about FS Bancorp from documents filed with the Securities and Exchange Commission, or the SEC, that are not included in or delivered with this proxy statement/prospectus. You can obtain any of the documents filed with or furnished to the SEC by FS Bancorp at no cost from the SEC’s website at www.sec.gov or by requesting them in writing or by telephone from FS Bancorp:

FS Bancorp, Inc.

6920 220^th Street SW

Mountlake Terrace, Washington 98043

Attn: Investor Relations

(425) 771-5299

All website addresses given in this proxy statement/prospectus are for information only and are not intended to be an active link or to adopt, endorse or incorporate any website information into this proxy statement/prospectus.

You should rely only on the information contained in, or incorporated by reference into, this proxy statement/prospectus. No one has been authorized to provide you with information that is different from that contained in, or incorporated by reference into, this proxy statement/prospectus. This proxy statement/prospectus is dated [●] [●], 2026, and you should assume that the information in this proxy statement/prospectus is accurate only as of such date. You should assume that the information incorporated by reference into this proxy statement/prospectus is accurate as of the date of the document that includes such information. Neither the mailing of this proxy statement/prospectus to Pacific West shareholders nor the issuance by FS Bancorp of FS Bancorp common shares in connection with the merger will create any implication to the contrary.

Please note that copies of this proxy statement/prospectus provided to you will not include exhibits, unless the exhibits are specifically incorporated by reference into this proxy statement/prospectus.

This proxy statement/prospectus does not constitute an offer to sell, or a solicitation of an offer to buy, any securities, or the solicitation of a proxy, in any jurisdiction to or from any person to whom it is unlawful to make any such offer or solicitation in such jurisdiction. Except where the context otherwise indicates, information contained in this proxy statement/prospectus regarding FS Bancorp has been provided by FS Bancorp and information contained in this proxy statement/prospectus regarding Pacific West has been provided by Pacific West.

If you would like to request documents, please do so by [●] [●], 2026 in order to receive them before Pacific West’s special meeting of shareholders. See the section entitled “Where You Can Find More Information” on page 106.

Pacific West Bancorp
2040 8^th Avenue

West Linn, Oregon 97068

NOTICE OF SPECIAL MEETING OF SHAREHOLDERS
 

TO OUR SHAREHOLDERS:

We are pleased to notify you of and invite you to attend a special meeting of shareholders, which is being held in lieu of our annual shareholder meeting as further described herein. At the special meeting, you will be asked to vote on the following matters:

Only shareholders of record at the close of business on [●] [●], 2026 are entitled to notice of, and to vote at, the special meeting and any adjournments or postponements of the special meeting. The affirmative vote of the holders of a majority of the outstanding Pacific West common shares as of that date is required to approve the merger agreement. The adjournment proposal will be approved if a majority of the votes cast are voted in favor of the proposal. We are not aware of any other business eligible to be considered at the special meeting and matters other than those set forth above are not eligible to be presented or considered during the meeting.

In connection with the proposed merger, you may exercise dissenters’ rights as provided under the Oregon Revised Statutes (“ORS”) 60.551 through 60.594. If you meet all of the requirements under applicable Oregon law, and follow all of its required procedures, you may receive cash in the amount equal to the fair value of your shares. The procedure for exercising your dissenters’ rights is summarized under the heading “Dissenters’ Rights” in the attached proxy statement/prospectus. The relevant Oregon statutory provisions regarding dissenters’ rights are attached to this document as Appendix C.

Pacific West’s board of directors has unanimously approved the merger agreement, believes that the merger agreement and the transactions contemplated thereby, including the merger, are in the best interests of Pacific West and its shareholders, and unanimously recommends that Pacific West shareholders vote “FOR” the approval of the merger agreement and “FOR” the adjournment proposal.

Your vote is very important. To ensure that your shares are voted at the special meeting, please follow the instructions that accompany your proxy card and cast your vote by internet, by telephone, or by returning your completed, signed, and dated proxy card in the enclosed envelope (please allow a minimum of 10 days for your proxy card to be processed).

TABLE OF CONTENTS

QUESTIONS AND ANSWERS ABOUT THE MERGER AND

THE PACIFIC WEST SPECIAL MEETING

The following are some of the questions that you, as a shareholder of Pacific West, may have and answers to those questions. These questions and answers, as well as the following summary, are not meant to be a substitute for the information contained in the remainder of this document, and this information is qualified in its entirety by the more detailed descriptions and explanations contained elsewhere in this document. We urge you to read this document in its entirety prior to making any decision as to your Pacific West common shares and the merger agreement.

Q1:          Why am I receiving this proxy statement/prospectus?

A1:          You are receiving this proxy statement/prospectus because our records indicate that you were the record or beneficial owner of shares of Pacific West common stock as of the [●], 2026, record date. If you have sold your shares since the record date, you are nevertheless eligible to vote your shares at the special meeting, and we ask that you do so in order to assure the presence of a quorum. However, you will be entitled to receive merger consideration or to exercise dissenters’ rights only with respect to shares you own at the effective time of the merger.

Q2:         Why do Pacific West and FS Bancorp want to merge?

A2.         We want to merge because we each believe the merger will benefit our shareholders, communities, customers and employees. Both Pacific West and FS Bancorp have long been committed to serving our respective local customers, and we believe the combination of our businesses will provide efficiencies of scale and an attractive geographic footprint that will benefit each of the above constituencies. In addition, the merger will allow Pacific West’s customers access to a number of products and services that we cannot presently offer on a cost-effective basis, and will expand the number of branch locations available to them.

Q3:          What will Pacific West shareholders receive in the merger?

A3:          The aggregate merger consideration to be issued to Pacific West shareholders in connection with the merger consists of $16,832,742 in cash and 430,176 shares of FS Bancorp common stock.

If the merger is completed, each share of Pacific West common stock outstanding immediately prior to the effective time of the merger, other than those for which dissenters’ rights are effectively elected and not forfeited or revoked, will be converted into the right to receive, at the holder’s election, either cash, which we refer to as the cash consideration, or shares of FS Bancorp common stock together with cash in lieu of a fractional share of FS Bancorp common stock, which we refer to as the stock consideration. As a Pacific West shareholder, you will have the opportunity to elect the form of consideration to be received for all shares of Pacific West common stock held by you, subject to the allocation and proration procedures set forth in the merger agreement and described in this proxy statement/prospectus. These allocation procedures are intended to ensure that the aggregate merger consideration allocates approximately equal value to each share of Pacific West common stock based on the average value of FS Bancorp common stock immediately prior to the effective time. The form of the merger consideration ultimately received by you will depend upon the election, allocation and proration procedures described in this proxy statement/prospectus and the choices of other Pacific West shareholders and may be different from what you elect.

Q4:          How will the amount of cash in the cash consideration and the number of shares of FS Bancorp common stock in the stock consideration be determined?

A4:         FS Bancorp common stock trades on the Nasdaq Capital Market under the symbol “FSBW”. The merger agreement provides that the amount of the cash consideration and the amount of stock consideration will be allocated so as to assure that each share of Pacific West common stock that utilizes the election process receives a value as nearly equal as possible at the time of the merger, with shares of FS Bancorp common stock valued based on the volume-weighted average trading price of FS Bancorp common stock for the ten Nasdaq trading days ending on the last trading day immediately preceding the closing date of the merger, which we refer to as the “Closing FS Bancorp Share Value.”

The merger agreement provides that value of the merger consideration into which each share of Pacific West common stock is converted, which we refer to as the per share amount, will be determined by adding (1) the amount of the aggregate cash consideration, $16,832,742 and (2) the value of 430,176 shares of FS Bancorp common stock, based on the Closing FS Bancorp Share Value (together, the “Closing Transaction Value”), and then dividing this sum by the number of shares of Pacific West common stock outstanding at the time of the merger (the “Aggregate Pacific West Share Amount”). Each share of Pacific West common stock will be converted into the right to receive either (1) an amount of cash equal to the per share cash consideration or (2) the fraction of a share of FS Bancorp common stock having a value equal to the per share amount divided by the Closing FS Bancorp Share Value (the “Exchange Ratio”), with cash in lieu of any resulting fractional share interests (the per share stock consideration).

The following table indicates the per share cash consideration and number of shares included in the per share stock consideration based on a hypothetical range of Closing FS Bancorp Share Value prices. The amounts assume that there will be 2,750,343 shares of Pacific West common stock outstanding at the time of the merger, which equals the number of shares of Pacific West common stock outstanding as of the date of this proxy statement/prospectus (2,707,530 shares), plus 42,813 shares underlying outstanding restricted stock awards.

Q5:          Will the value of the aggregate merger consideration change between the date of this proxy statement/prospectus and the time the merger is completed?

A5:          Yes. The value of FS Bancorp’s common stock will fluctuate between the date of this proxy statement/prospectus and the completion of the merger based upon the trading price of FS Bancorp common stock. While the aggregate amounts of the cash consideration and number of shares of FS Bancorp common stock in the stock consideration are fixed, fluctuations in the market price of FS Bancorp common stock after the date of this proxy statement/prospectus will change the amount of the per share cash consideration and per share stock consideration received by Pacific West shareholders. Please see the table included in the answer to the immediately preceding question for an illustration of how these amounts may change as the FS Bancorp average share price changes.

Q6:          How do I elect the form of merger consideration that I prefer?

A6:          If you are a Pacific West shareholder, accompanying this proxy statement/prospectus is a form that will allow you to elect to receive the stock consideration or cash consideration for all of the Pacific West stock you own or to indicate that you have no preference. These election forms must be returned separately no later than the deadline stated in the election materials. If you hold your shares in “street name” through a bank or broker, your bank or broker will separately provide instructions for making your election with respect to such shares. For more information, see “The Merger Agreement – Consideration to be Received in the Merger” on page 47, “– Cash or Stock Election and Allocation and Proration Procedures” beginning on page 48.

Q7:          What will holders of Pacific West restricted stock awards receive in the merger?

A7:          At the effective time of the merger, each unvested award of Pacific West restricted stock issued under Pacific West’s Restricted Shares Plan will vest and will be converted into the right to receive the per share merger consideration in the same manner and amount as other shares of outstanding Pacific West common stock. Holders of such stock awards will be permitted to elect to receive the stock consideration or cash consideration for such shares in the same manner and subject to the same limitations as other Pacific West shareholders.

Q8:         What is being voted on at the special meeting?

A8:         Pacific West shareholders will be voting on the approval of the merger agreement, as well as a proposal of the Pacific West board of directors to adjourn or postpone the special meeting, if necessary or appropriate to solicit additional proxies in favor of the merger agreement (which we refer to as the “adjournment proposal”).

Q9:         Who is entitled to vote at the special meeting?

A9:         Pacific West shareholders of record at the close of business on [●] [●], 2026, the record date for the special meeting, are entitled to receive notice of and to vote on matters that come before the special meeting and any adjournments or postponements of the special meeting. However, a Pacific West shareholder may only vote his or her shares if he or she is present in person or if his or her shares are represented by proxy at the special meeting.

Q10:         How do I vote?

A10:         After carefully reading and considering the information contained in this document, please follow the instructions that accompany your proxy card and cast your vote as soon as possible by internet, by telephone, or by returning your completed, signed, and dated proxy card in the enclosed envelope (please allow a minimum of 10 days for your proxy card to be processed). You also may attend the special meeting and vote in person. Even if you are planning to attend the special meeting, we request that you cast your vote by internet, by telephone or by proxy card. For more detailed information, please see the section entitled “The Special Meeting” of Pacific West shareholders beginning on page 26. If your shares are held in “street name,” through a bank, broker, or other nominee, that institution will send you separate instructions describing the procedure for voting such shares. Please follow the voting instructions provided by your bank, broker, or other nominee. Note that if your common shares are held in “street name” through a bank, broker, or other nominee, you cannot vote your shares by returning a proxy card directly to Pacific West Bancorp, or by voting in person at the special meeting, unless you first obtain and submit a “legal proxy” from your bank, broker, or nominee.

Q11:      How many votes do I have?

A11:         Each Pacific West common share that you own as of the record date entitles you to one vote. As of the close of business on June [●], 2026, there were 2,707,530 outstanding Pacific West common shares. As of that date, approximately 25.6% of the outstanding Pacific West common shares entitled to vote were held by directors and executive officers of Pacific West and their respective affiliates. As an inducement for FS Bancorp to enter into the merger agreement, each Pacific West director and executive officer has agreed to vote “FOR” approval of the merger agreement and “FOR” approval of the adjournment proposal.

Q12:       What constitutes a quorum at the special meeting?

A12:         The presence of the holders of a majority of shares entitled to vote at the special meeting constitutes a quorum. Presence may be in person or by proxy. You will be considered part of the quorum if you vote by internet, if you vote by telephone, if you return a signed and dated proxy card, or if you vote in person at the special meeting. If your shares are held through a broker or nominee, your shares will be counted for purposes of a quorum if you vote following the instructions from that firm.

Q13:      Why is my vote important?

A13:         If you do not vote by proxy or in person at the special meeting, it will be more difficult for Pacific West to obtain the necessary quorum to hold its special meeting. In addition, if you fail to vote, by proxy or in person, it will have the same effect as a vote against approval of the merger agreement (sometimes referred to herein as “plan of merger”). The merger agreement must be approved by the holders of a majority of the outstanding Pacific West common shares entitled to vote at the special meeting. If you are the record holder of your shares (meaning a share certificate has been issued in your name and/or your name appears on Pacific West’s stock ledger) and you respond but do not indicate how you want to vote, your proxy will be counted as a vote in favor of approval of the merger agreement, as well as a vote in favor of approval of the adjournment proposal. If your shares are held in street name with a broker, your broker will vote your shares on the merger agreement proposal only if you provide instructions to it on how to vote. Shares that are not voted because you do not properly instruct your broker will have the effect of votes against approval of the merger agreement.

If you respond and abstain from voting, your abstention will have the same effect as a vote against approval of the merger agreement but will have no effect on the adjournment proposal.

Q14:       What is the recommendation of the Pacific West board of directors?

A14:         The Pacific West board of directors unanimously recommends a vote “FOR” approval of the merger agreement and “FOR” approval of the adjournment proposal.

Q15:      What if I return my proxy but do not mark it to show how I am voting?

A15:         If your proxy card is signed and returned without specifying your choice, your shares will be voted in favor of approval of both the merger agreement and adjournment proposal in accordance with the recommendation of the Pacific West board of directors.

Q16:       Can I change my vote after I have mailed my signed proxy card?

A16:         Yes. If you are a holder of record of Pacific West common shares, you may revoke your proxy at any time before it is voted by:

● voting by internet at a later time but prior to the special meeting,

● signing and timely returning a proxy card with a later date,

● delivering a written revocation to Pacific West’s corporate secretary, or

● attending the special meeting in person and voting by ballot at the special meeting.

Attendance at the special meeting by itself will not automatically revoke your proxy. A revocation or later-dated proxy received by Pacific West after the vote is taken at the special meeting will not affect your previously submitted proxy. Pacific West’s corporate secretary’s mailing address is: Corporate Secretary, Pacific West Bancorp, 2040 8^th Avenue, West Linn, Oregon 97068. If your shares are held in “street name” through a bank or broker, you should contact your bank or broker to change your voting instructions.

Q17:      What regulatory approvals are required to complete the merger?

A17:         Promptly following the merger, Pacific West’s subsidiary bank, Pacific West Bank, will be merged with and into FS Bancorp’s subsidiary bank, 1st Security Bank, which we often refer to in this document as the “bank merger.” In order to complete the merger, FS Bancorp and Pacific West must first obtain all regulatory approvals, consents and orders required in connection with the merger and the bank merger. Accordingly, the parties must obtain the approval of or waiver by the Board of Governors of the Federal Reserve System (the “Federal Reserve Board”), and the approval of the Federal Deposit Insurance Corporation (the “FDIC”), the Oregon Division of Finance and Corporate Securities (“Oregon Division”) and the Washington State Department of Financial Institutions (the “Washington DFI”). Applications were filed with the FDIC, Oregon Division and Washington DFI on March 18, 2026. FS Bancorp submitted an application to the Federal Reserve Board on May 5, 2026. The Oregon Division and the Washington DFI have approved the bank merger on June 17, 2026 and June 18, 2026, respectively, and such approvals are subject to the approval of the FDIC and the Federal Reserve Board.

Q18:       Do I have dissenters’ or appraisal rights with respect to the merger?

A18:         Yes. Under Oregon law, you have the right to dissent from the merger. To exercise dissenters’ rights of appraisal you must strictly follow the procedures prescribed by the Oregon Revised Statutes, or the ORS. To review these procedures in more detail, see the section entitled “Dissenters’ Rights” beginning on page 104, and Appendix C of this proxy statement/prospectus.

Q19:      What are the material U.S. federal income tax consequences of the merger to me?

A19:         The merger is expected to qualify for U.S. federal income tax purposes as a “reorganization” within the meaning of Section 368(a) of the Internal Revenue Code of 1986, as amended, which we refer to throughout this proxy statement/prospectus as the Code. However, neither FS Bancorp nor Pacific West will request or receive a ruling from the Internal Revenue Service (the “IRS”) that the merger will qualify as a reorganization. Assuming the merger qualifies as a reorganization, the U.S. federal income tax consequences to U.S. holders of Pacific West common stock will depend primarily on whether they exchange their Pacific West common shares solely for FS Bancorp common shares or solely for cash, or whether they receive a combination of FS Bancorp common shares and cash pursuant to the allocation and proration procedures set forth in the merger agreement. It is expected that U.S. holders of Pacific West common shares will not recognize gain or loss for U.S. federal income tax purposes upon the exchange of their Pacific West common shares solely for FS Bancorp common shares pursuant to the merger, except with respect to any cash received by a Pacific West shareholder in lieu of a fractional FS Bancorp common share. Those shareholders will retain a basis in their shares of FS Bancorp common stock equal to their basis in the Pacific West common stock surrendered in the exchange. U.S. holders of Pacific West common shares who exchange their shares solely for cash will recognize gain or loss on the exchange. U.S. holders of Pacific West common shares who receive a combination of FS Bancorp common shares and cash will recognize gain (but not loss) in an amount equal to the lesser of (i) the amount by which the sum of the fair market value of the FS Bancorp common shares (determined as of the effective time of the merger) and cash received by such U.S. holder of Pacific West common shares in the merger exceeds such U.S. holder’s adjusted tax basis in the holder’s Pacific West common shares surrendered and (ii) the amount of cash received by such U.S. holder of Pacific West common shares (in each case excluding any cash received in lieu of a fractional FS Bancorp common share, with the gain or loss on such fractional share determined separately, as discussed below under “Material U.S. Federal Income Tax Consequences of the Merger— Cash Received in Lieu of a Fractional FS Bancorp Common Share”). Gain or loss is determined separately with respect to each block of Pacific West common shares. If a U.S. holder receives a combination of FS Bancorp common shares and cash (other than cash received in lieu of a fractional FS Bancorp common share) in exchange for Pacific West common shares pursuant to the merger and determines that it has a loss with respect to any block of shares, such loss cannot be recognized as part of the merger and cannot be used to offset any gain realized on another block of shares. The actual U.S. federal income tax consequences to U.S. holders of Pacific West common shares of electing to receive cash or FS Bancorp common shares will not be ascertainable at the time you make your election because it will not be known at that time how, or to what extent, the allocation and proration procedures will apply, nor will the actual values of the stock consideration and the cash consideration be known at that time. In addition, Pacific West shareholders will recognize gain or loss if they exercise dissenters’ rights. Please see "Material U.S. Federal Income Tax Consequences of the Merger” beginning on page 95 for further discussion of the material U.S. federal income tax consequences of the merger.

The tax treatment set forth above may not apply to all U.S. holders. Tax matters are complicated, and the tax consequences of the merger to a particular Pacific West shareholder will depend in part on such shareholder’s individual circumstances. Accordingly, to get a full understanding of the merger’s tax consequences that are particular to you, you should consult your own independent tax advisors regarding the particular tax consequences of the merger, including the applicability and effect of U.S. federal, state, local and non-U.S. tax laws, including tax return reporting requirements and the effect of any recent or proposed change in applicable tax laws.

Q20:       Does the merger require the approval of FS Bancorp shareholders?

A20:         No. Because FS Bancorp will be the surviving corporation in the merger and because the stock component represents less than twenty percent of FS Bancorp’s common stock, the approval of FS Bancorp’s shareholders is not required and is not being sought.

Q21:      What risks should I consider before I vote on the merger?

A21:         We encourage you to read carefully the detailed information about the merger contained in this document, including the section entitled “Risk Factors” beginning on page 14.

Q22:      When do you expect to complete the merger?

A22:         We are working to complete the merger during the quarter ending September 30, 2026. We must first obtain the necessary regulatory approvals and the approval of Pacific West’s shareholders at the special meeting. In the event of delays, the date for completing the merger can occur as late as December 31, 2026, after which Pacific West and FS Bancorp would need to mutually agree to extend the closing date of the merger. We cannot assure you as to if or when all the conditions to the merger will be met. It is possible we will not complete the merger.

Q23:      What happens if the merger is not approved?

A23:         If the merger is not approved, or if it is abandoned or terminated for any other reason, each party will continue its operations independently. As described below in “Background of the Merger,” Pacific West has suffered challenges in its ability to grow organically, and the termination of the merger agreement is likely to exacerbate those challenges by limiting the potential for a strategic combination with another financial institution. Further, Pacific West is likely to incur additional costs, which may be material, in adopting and pursuing other growth opportunities. The abandonment or termination of the merger may also make it more difficult for Pacific West to attract and retain employees and customers, and may impair relationships with its vendors. These effects are also likely to have a material adverse effect on the trading value of Pacific West’s common stock and may invite additional scrutiny from shareholder plaintiffs, regulatory authorities and other constituencies. Please see “Risk Factors.”

Q24:      What happens if the merger is not completed?

A24:          If the merger is not completed, holders of Pacific West common shares will not receive any consideration for their shares in connection with the merger. Instead, Pacific West will remain an independent company and its common shares will continue to be traded on the OTCID Basic Market. In addition, if the merger agreement is terminated under certain circumstances, a termination fee may be required to be paid by Pacific West. See “The Merger Agreement—Termination of the Merger Agreement” beginning on page 57 for a complete discussion of the circumstances under which a termination fee would be required to be paid.

Q25:       Will I be able to sell any shares of FS Bancorp common stock I receive pursuant to the merger?

A25:         Yes. The FS Bancorp common stock issued pursuant to the merger will be registered under the Securities Act of 1933, as amended (the “Securities Act”), and FS Bancorp will cause the shares issued in the merger to be listed on the Nasdaq Capital Market. To the extent that Pacific West shareholders receive shares of FS Bancorp common stock as merger consideration pursuant to the merger, it will be freely transferable unless you are deemed to be an affiliate of FS Bancorp. Affiliates of FS Bancorp will be able to sell shares, they receive pursuant to the merger subject to applicable restrictions and securities regulations. See the section entitled “The Merger — Resale of FS Bancorp Common Stock”. We are not aware of any Pacific West shareholder who will become an affiliate of FS Bancorp as a result of the merger.

Q26:       If I am a holder of Pacific West common shares in certificated form, should I send in my Pacific West share certificates now?

A26:         No. Please send in your Pacific West share certificates with your election form and letter of transmittal. If you don’t send your certificates with your election form, after completion of the merger, the exchange agent will send you a letter of transmittal and instructions for exchanging Pacific West share certificates for the merger consideration. See “The Merger Agreement—Exchange Procedures.”

Q27:      What should I do if I hold my Pacific West common shares in book-entry form at a bank or broker?

A27:         You are not required to take any special additional actions if your Pacific West common shares are held in book-entry form at a bank or broker. After the completion of the merger, the exchange agent will send you instructions for converting your book-entry shares for the merger consideration. See “The Merger Agreement—Exchange Procedures.”

Q28:      Whom should I contact with questions or to obtain additional copies of this document?

A28:       Pacific West Bancorp

2040 8^th Avenue
West Linn, Oregon 97068
Attn: Investor Relations
(503) 905-2222

RISK FACTORS

By voting in favor of the merger agreement, you will be choosing to invest in the common shares of FS Bancorp as combined with Pacific West. An investment in the combined company’s common shares involves a high degree of risk. In addition to the other information included in or incorporated by reference into this proxy statement/prospectus, including the matters addressed in the section entitled “Cautionary Statement Regarding Forward-Looking Statements” on page 18, you should carefully consider the matters described below in determining whether to vote in favor of approval of the merger agreement. Please see the section entitled “Where You Can Find More Information.”

Risks Related to the Merger

Because the market price of FS Bancorp common stock will fluctuate, Pacific West shareholders cannot be certain of the value of the merger consideration that they will receive upon completion of the merger.

Upon completion of the merger, Pacific West shareholders will receive either cash or shares of FS Bancorp common stock for all of the Pacific West common stock they hold immediately prior to the completion of the merger. While the aggregate merger consideration is fixed at $16,832,742 cash and 430,176 shares of FS Bancorp common stock, the merger agreement provides a mechanism to allocate the shares and the cash so that, as nearly as practicable, each Pacific West share utilizing the election process will receive approximately equivalent value determined as of the closing date. Thus, the amount of cash or the number of shares into which each share of Pacific West common stock is converted will depend on the Closing FS Bancorp Share Value and the number of shares of Pacific West common stock outstanding at the time of the merger. Therefore, the value of the aggregate merger consideration, the amount of the per share cash consideration and the number of shares of FS Bancorp common stock in the per share stock consideration will fluctuate between the date of this proxy statement/prospectus and the completion of the merger. The market price of FS Bancorp common stock may fluctuate as a result of a variety of factors, including general market and economic conditions, changes in business, operations and prospects, and regulatory considerations, and the risks and uncertainties set forth in this section entitled “Risk Factors.” Many of these factors are outside our control. You should obtain current market quotations for FS Bancorp’s common stock before deciding how to vote on the merger and before electing your preferred form of merger consideration. Neither FS Bancorp nor Pacific West is permitted to terminate the merger agreement as a result, in and of itself, of any increase or decrease in the market price of FS Bancorp common stock or Pacific West common stock.

Accordingly, at the time of the Pacific West special meeting, Pacific West shareholders will not know or be able to calculate the number of shares of FS Bancorp common stock or the amount of cash that they will receive upon completion of the merger.

The form of merger consideration that Pacific West shareholders ultimately receive may be different from the form elected.

All Pacific West shareholders will be permitted to make an election as to the preferred form of consideration they wish to receive. The exchange agent will, subject to limitations set forth in the merger agreement, adjust the form of consideration that a Pacific West shareholder will receive in order to ensure that all shares of Pacific West common stock are converted into a pro rata share of an aggregate pool consisting of $16,832,742 in cash and 430,176 shares of FS Bancorp common stock. Consequently, if either the stock consideration or the cash consideration is oversubscribed, you may receive a different form of merger consideration from the form you elect, which, among other things, may result in different tax consequences than you anticipated (including the recognition of gain for U.S. federal income tax purposes with respect to the cash received). If you do not make an election and do not perfect dissenters’ rights, you will receive the merger consideration in cash or shares as provided for in the merger agreement.

The price of FS Bancorp common stock might decrease after the merger.

Upon completion of the merger, Pacific West shareholders who receive some or all of their merger consideration in the form of FS Bancorp common stock (whether because of their election or because of the reallocation provisions described in this proxy statement/prospectus) will become shareholders of FS Bancorp. FS Bancorp common stock could decline in value after the merger. For example, during the twelve-month period ending on [●] [●], 2026 (the most recent practicable date before the printing of this document), the closing price of FS Bancorp common stock varied from a low of $[●] to a high of $[●] and ended that period at $[●]. The market value of FS Bancorp common stock fluctuates based upon general market conditions, FS Bancorp’s business, operations, financial performance, prospects and other factors. Further, the market price of FS Bancorp common stock after the merger may be affected by factors different from those currently affecting FS Bancorp common stock. The businesses of FS Bancorp and Pacific West differ and, accordingly, the results of operations of the combined company and the market price of the combined company’s shares of common stock may be affected by factors different from those currently affecting the independent results of operations of FS Bancorp and Pacific West and the market price of common stock of FS Bancorp prior to the merger.

Pacific West’s shareholders will have less influence as shareholders of FS Bancorp than as shareholders of Pacific West.

Pacific West’s shareholders currently have the right to vote in the election of the board of directors of Pacific West and on other matters affecting Pacific West. Following the merger, the shareholders of Pacific West as a group will hold an ownership interest of approximately [●]% of FS Bancorp. Once the merger occurs, each Pacific West shareholder who becomes a shareholder of FS Bancorp will have a percentage ownership of the combined company that is much smaller than such shareholder’s percentage ownership of Pacific West. Because of this, Pacific West’s shareholders will have less influence on the management and policies of FS Bancorp than they now have on the management and policies of Pacific West.

If FS Bancorp is unable to integrate the combined operations successfully, its business and earnings may be negatively affected.

The merger involves the integration of companies that have previously operated independently. Successful integration of Pacific West’s operations will depend primarily on FS Bancorp’s ability to consolidate operations, systems and procedures and to eliminate redundancies and costs. No assurance can be given that FS Bancorp will be able to integrate its post-merger operations without encountering difficulties including, without limitation, the loss of key employees and customers, the incurrence of unexpected costs, the disruption of the ongoing business of FS Bancorp or Pacific West or possible inconsistencies in standards, controls, procedures and policies. Anticipated economic benefits of the merger are projected to come from various areas that FS Bancorp’s management has identified through the due diligence and integration planning process. The elimination and consolidation of duplicate tasks are projected to result in annual cost savings. If FS Bancorp has difficulties with the integration, it might not fully achieve the economic benefits it expects to result from the merger. In addition, FS Bancorp may experience greater than expected costs or difficulties relating to the integration of the business of Pacific West, and/or may not realize expected cost savings from the merger within the expected time frame.

The fairness opinion of Pacific West’s financial advisor received by Pacific West’s board of directors prior to signing of the merger agreement does not reflect changes in circumstances since the signing of the merger agreement.

Changes in the operations and prospects of FS Bancorp or Pacific West or general market and economic conditions, and other factors that may be beyond the control of FS Bancorp and Pacific West, may alter the value of FS Bancorp or Pacific West or the prices of FS Bancorp common shares or Pacific West common shares by the time the merger is completed. The opinion of Pacific West’s financial advisor, dated February 25, 2026, does not speak as of the time the merger will be completed or as of any date other than the date of such opinion. For a description of the opinion of Pacific West’s financial advisor, please refer to “The Merger—Opinion of Pacific West’s Financial Advisor.” For a description of the other factors considered by the board of directors of Pacific West in determining to approve the merger agreement, please refer to “The Merger—Recommendation of the Pacific West Board of Directors and Reasons of Pacific West for the Merger.”

The merger agreement limits Pacific West’s ability to pursue alternatives to the merger.

The merger agreement contains non-solicitation provisions that, subject to limited exceptions, limit Pacific West’s ability to discuss, facilitate or commit to competing third-party proposals to acquire all or a significant part of Pacific West. Although Pacific West’s board of directors is permitted to take certain actions in connection with the receipt of a competing acquisition proposal if it determines in good faith that the failure to do so would violate its fiduciary duties, taking such actions could, and other actions (such as withdrawing or modifying its recommendation to Pacific West shareholders that they vote in favor of approval of the merger agreement) would, entitle FS Bancorp to terminate the merger agreement and receive a termination fee of $1.25 million. See the section entitled “The Merger Agreement—Termination of the Merger Agreement” on page 57. These provisions could discourage a potential competing acquiror even if it were prepared to pay consideration with a higher per share price than that proposed in the merger, or might result in a potential competing acquiror proposing to pay a lower per share price to acquire Pacific West than it might otherwise have proposed to pay. The payment of the termination fee could also have an adverse impact on Pacific West’s financial condition.

Pacific West will be subject to business uncertainties and contractual restrictions while the merger is pending.

FS Bancorp and Pacific West have operated and, until the completion of the merger, will continue to operate, independently. Uncertainty about the effect of the merger on employees and customers may have an adverse effect on Pacific West and consequently on FS Bancorp. These uncertainties may impair Pacific West’s ability to attract, retain or motivate key personnel until the merger is consummated, and could cause customers and others that deal with Pacific West to seek to change existing business relationships with Pacific West. Retention of certain employees may be challenging during the pendency of the merger, as some employees may experience uncertainty about their future roles with FS Bancorp. If key employees depart because of issues relating to the uncertainty and difficulty of integration or a desire not to remain with FS Bancorp, FS Bancorp’s business following the merger could be harmed. In addition, the merger agreement restricts Pacific West from making certain investments and taking other specified actions until the merger occurs without the consent of FS Bancorp. Subject to certain specified exceptions, the merger agreement also obligates Pacific West and Pacific West Bank to conduct business in the ordinary course in all material respects and to use reasonable best efforts to maintain and preserve intact Pacific West’s business organization and advantageous business relationships. These restrictions may prevent Pacific West from pursuing attractive business opportunities that may arise prior to the completion of the merger. See “The Merger Agreement—Conduct of Business Pending the Merger.”

Pacific West’s directors and executive officers have additional interests in the merger.

In deciding how to vote on the approval of the merger agreement, you should be aware that some of Pacific West’s directors and executive officers have interests in the merger that are different from, or in addition to, the interests of Pacific West shareholders generally. See the section entitled “The Merger—Interests of Certain Persons in the Merger.” Pacific West’s board of directors was aware of these interests and considered them when it recommended approval of the merger agreement to the Pacific West shareholders.

Regulatory approvals may not be received, may take longer than expected or may impose conditions that are not presently anticipated or that could have an adverse effect on FS Bancorp following the merger.

Before the merger and the bank merger may be completed, FS Bancorp and Pacific West must obtain approvals from the FDIC, the Oregon Division, the Washington DFI, and the Federal Reserve Board. Other approvals, waivers or consents from regulators may also be required. An adverse development in either party’s regulatory standing or other factors could result in an inability to obtain approvals or delay their receipt. These regulators may impose conditions on the completion of the merger or the bank merger or require changes to the terms of the merger or the bank merger. While FS Bancorp and Pacific West do not currently expect that any such conditions or changes will be imposed, there can be no assurance that they will not be, and such conditions or changes could have the effect of delaying completion of the merger or imposing additional costs on or limiting the revenues of FS Bancorp following the merger, any of which might have an adverse effect on FS Bancorp following the merger. FS Bancorp is not obligated to complete the merger if the regulatory approvals received in connection with the completion of the merger impose any unduly burdensome condition upon FS Bancorp following the merger or 1st Security Bank following the bank merger. See “The Merger—Regulatory Approvals Required for the Merger” and “The Merger Agreement—Conditions to Completion of the Merger.”

The merger is subject to certain closing conditions that, if not satisfied or waived, will result in the merger not being completed, which may cause the price of FS Bancorp common shares or Pacific West common shares to decline.

The merger is subject to customary conditions to closing, including the receipt of required regulatory approvals and approval of Pacific West’s shareholders. If any condition to the merger agreement is not satisfied or waived, to the extent permitted by law, the merger will not be completed. In addition, FS Bancorp and Pacific West may terminate the merger agreement under certain circumstances, even if Pacific West’s shareholders approve the merger agreement. If FS Bancorp and Pacific West do not complete the merger, the trading prices of FS Bancorp common shares or Pacific West common shares may decline. In addition, neither company would realize any of the expected benefits of having completed the merger. If the merger is not completed and Pacific West’s board of directors seeks another merger or business combination, Pacific West shareholders cannot be certain that Pacific West will be able to find a party willing to offer equivalent or more attractive consideration than the consideration FS Bancorp has agreed to provide, particularly in light of the process that Pacific West conducted as described in “Background of the Merger.” If the merger is not completed, additional risks could materialize, which could materially and adversely affect the business, financial condition and results of FS Bancorp and Pacific West, including the recognition of the expenses relating to the merger without realizing the economic benefits of the merger. For more information on closing conditions to the merger agreement, see “The Merger Agreement— Conditions to Completion of the Merger” included elsewhere in this proxy statement/prospectus.

The merger agreement and termination fee provisions may discourage competing acquisition proposals for Pacific West.

Until completion of the merger, Pacific West is generally prohibited under the merger agreement from soliciting, initiating, encouraging, or participating in discussions or negotiations regarding any inquiry or proposal that could reasonably be expected to lead to an acquisition proposal from a third party. While the Pacific West board of directors may take certain actions in response to a competing acquisition proposal if it determines in good faith that failing to do so would violate its fiduciary duties, taking such actions, or other actions, such as withdrawing or modifying its recommendation to Pacific West shareholders in favor of the merger, could entitle FS Bancorp to terminate the merger agreement and receive a termination fee of $1.25 million. See the section entitled “The Merger Agreement — Termination of the Merger Agreement” beginning on page 57.

These provisions, including the termination fee, could discourage other companies from seeking to acquire Pacific West, even if a third party were willing to propose a transaction that offers greater value to Pacific West shareholders than the merger consideration currently being offered. They could also result in a competing acquiror proposing a lower per-share price than it otherwise might have offered. In addition, the payment of the termination fee could have an adverse effect on Pacific West’s financial condition.

Litigation related to the merger could delay completion or result in significant costs, which may adversely affect FS Bancorp and its shareholders.

In connection with the merger, shareholders of FS Bancorp or Pacific West may file putative class action or other lawsuits against the boards of directors of either company, including actions seeking to enjoin or otherwise challenge the merger. The outcome of any such litigation is uncertain. If any lawsuit is not dismissed or resolved through settlement, it could delay or prevent completion of the merger and result in substantial costs to FS Bancorp and Pacific West, including potential indemnification obligations. Additionally, the defense or resolution of any unresolved claims at the time the merger is completed could adversely affect the combined company’s business, financial condition, results of operations, cash flows, or the market price of FS Bancorp common stock.

The termination or abandonment of the merger may cause one or both parties to recognize increased expenses or to experience disruption in its business.

If the merger agreement is terminated for any reason prior to consummation of the merger, either or both parties may incur significant expenses reflecting, among other things, the cost of occupancy and operating expense, increased legal and accounting fees, and compensation expense necessary to retain existing personnel or attract replacement personnel. In Pacific West’s case, these costs may be material. Further, either party may find it necessary to modify their business strategy to address matters that are currently expected to be addressed in the merger. These costs and changes in strategy, and the resulting distractions and disruptions to the parties’ respective businesses, may result in a material adverse effect on the respective parties and on the prices of their common stock.

Recent rulings from the U.S. Supreme Court could result in material changes to U.S. federal income tax regulatory authority and administrative interpretations of established rules.

The Supreme Court's decision in Loper Bright Enterprises v. Raimondo could significantly impact the Treasury Department's (“Treasury”) and IRS’s authority to interpret the Code and regulations pursuant to the Code (“Treasury Regulations”). This may affect: (i) the validity and enforceability of existing Treasury Regulations, particularly where Congressional authorization is not explicit; (ii) the deference courts give to IRS interpretations, revenue rulings, notices, and other administrative guidance; (iii) treatment of tax positions previously taken based on Treasury Regulations or IRS guidance; (iv) the IRS's ability to adopt new interpretations or create new rules without specific statutory authorization; (v) the continued validity of tax planning strategies that rely on Treasury Regulations; and (vi) the level of certainty available through IRS private letter rulings and other administrative determinations. Any judicial reexamination of Treasury and IRS authority could result in increased tax uncertainty and compliance costs, the need to reevaluate and potentially restructure existing arrangements, greater risk of challenge to tax positions based on regulatory interpretations, reduced availability of administrative guidance and different courts reaching inconsistent conclusions about regulatory validity. Any such change could materially affect the intended U.S. federal income tax treatment of the merger.

Risks Relating to FS Bancorp and FS Bancorp’s Business

FS Bancorp is, and will continue to be, subject to the risks described in FS Bancorp’s Annual Report on Form 10-K for the fiscal year ended December 31, 2025, as updated by subsequent Quarterly Reports on Form 10-Q and Current Reports on Form 8-K, all of which are filed with the SEC and incorporated by reference into this proxy statement/prospectus. See “Where You Can Find More Information” included elsewhere in this proxy statement/prospectus.

CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTS

This document, including information included or incorporated by reference in this document, may contain forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended (the “Securities Act”), and Section 21E of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), and FS Bancorp and Pacific West intend for such forward-looking statements to be covered by the safe harbor provisions for forward-looking statements contained in the Private Securities Litigation Reform Act of 1995. These forward-looking statements include, but are not limited to, (i) statements about the benefits of the merger, including future financial and operating results, cost savings, enhancements to revenue and accretion to reported earnings that may be realized from the merger; (ii) statements about our respective plans, objectives, expectations and intentions and other statements that are not historical facts; (iii) statements about expectations regarding the timing of the closing of the merger and the ability to obtain regulatory approvals on a timely basis; and (iv) other statements identified by words such as “expects,” “projects,” “anticipates,” “intends,” “plans,” “believes,” “seeks,” “estimates,” “possible,” “potential,” “strategy,” or words of similar meaning. These forward-looking statements are based on current beliefs and expectations of FS Bancorp’s and Pacific West’s respective management and are inherently subject to significant business, economic and competitive uncertainties and contingencies, many of which are difficult to predict and beyond FS Bancorp’s and Pacific West’s control. In addition, these forward-looking statements are subject to assumptions with respect to future business strategies and decisions that are subject to change.

The following factors, among others, could cause actual results to differ materially from the anticipated results or other expectations expressed in the forward-looking statements:

Additional factors that could cause actual results to differ materially from those expressed in the forward-looking statements are discussed under “Risk Factors” beginning on page 14 and in FS Bancorp’s reports filed with the SEC. See the section entitled “Where You Can Find More Information.”

For any forward-looking statements made in this proxy statement/prospectus or in any documents incorporated by reference into this proxy statement/prospectus, FS Bancorp and Pacific West claim the protection of the safe harbor for forward-looking statements contained in the Private Securities Litigation Reform Act of 1995. You are cautioned not to place undue reliance on these statements, which speak only as of the date of this proxy statement/prospectus or the date of the applicable document incorporated by reference in this proxy statement/prospectus. FS Bancorp and Pacific West do not undertake to update forward-looking statements to reflect facts, circumstances, assumptions or events that occur after the date the forward-looking statements are made. All subsequent written and oral forward-looking statements concerning the merger or other matters addressed in this proxy statement/prospectus and attributable to FS Bancorp, Pacific West or any person acting on their behalf are expressly qualified in their entirety by the cautionary statements contained or referred to in this proxy statement/prospectus.

SELECTED CONSOLIDATED FINANCIAL INFORMATION OF FS BANCORP

FS Bancorp is providing the following information to aid you in your analysis of the financial aspects of the merger. FS Bancorp derived the information as of and for each of the five years ended December 31, 2021 through December 31, 2025 from its historical audited consolidated financial statements for these fiscal years. The consolidated financial information contained herein is the same historical information that FS Bancorp has presented in its prior filings with the SEC.

This information is only a summary, and you should read it in conjunction with FS Bancorp’s consolidated financial statements and notes thereto contained in FS Bancorp’s 2025 Annual Report on Form 10-K, which has been incorporated by reference into this document. See the section entitled “Where You Can Find More Information” on page 106.

____________________

SELECTED CONSOLIDATED FINANCIAL INFORMATION OF PACIFIC WEST

Pacific West is providing the following information to aid you in your analysis of the financial aspects of the merger. Pacific West derived the information as of and for each of the five years ended December 31, 2021 through December 31, 2025 from its historical audited consolidated financial statements for these fiscal years.

This information is only a summary, and you should read it in conjunction with Pacific West’s consolidated financial statements and notes thereto contained in Pacific West’s 2025 audited financial statements contained in Appendix D.

MARKET PRICE DATA AND DIVIDEND INFORMATION

Comparative Market Price Information

The following table presents trading information for FS Bancorp common shares on the Nasdaq Capital Market and Pacific West common shares on the OTCID Basic Market on February 24, 2026, the last trading day prior to the announcement of the signing of the merger agreement, and on June [●], 2026, the last practicable trading day for which information was available prior to the date of the printing of this proxy statement/prospectus.

You should obtain current market quotations for FS Bancorp common shares. The market price of FS Bancorp common shares will likely fluctuate between the date of this document and the date on which the merger is completed and after the merger. Because the market price of FS Bancorp common shares is subject to fluctuation, the value of the FS Bancorp common shares that you may receive in the merger may increase or decrease prior to and after the merger.

Historical Market Prices and Dividend Information

FS Bancorp common shares are listed on the Nasdaq Capital Market under the symbol “FSBW.” Pacific West common shares are listed on the OTCID Basic Market under the symbol “PWBK.” The following table sets forth, for the calendar quarters indicated, the high and low sales prices per FS Bancorp common share as reported on Nasdaq and the Pacific West common shares as reported on the OTCID Basic Market, and the FS Bancorp quarterly cash dividends per share declared. Pacific West has not paid any dividends and does not expect to pay dividends for the foreseeable future.

* Includes FS Bancorp special dividend of $0.22 per share for the quarter ended September 30, 2025.

As a bank holding company, Pacific West’s ability to pay dividends is subject to the guidelines of the Federal Reserve Board regarding capital adequacy and dividends. The Federal Reserve Board’s policy is that a bank holding company should pay cash dividends only to the extent that its net income for the past year is sufficient to cover both the cash dividends and a rate of earnings retention that is consistent with the holding company’s capital needs, asset quality and overall financial condition, and that it is inappropriate for a bank holding company experiencing serious financial problems to borrow funds to pay dividends. Under Oregon law, Pacific West is prohibited from paying a dividend if, after paying the dividend, Pacific West would be unable to pay its debts as they become due in the usual course of business, or if its total liabilities, plus the amount that would be needed, in the event it were to be dissolved at the time of the dividend payment, to satisfy preferential rights on dissolution of holders of preferred shares ranking senior in right of payment to the capital stock on which the applicable distribution is to be made would exceed its total assets.

The primary source for dividends paid to Pacific West shareholders is dividends received from Pacific West Bank. There are regulatory restrictions on the ability of Pacific West Bank to pay dividends. Under federal regulations, the dollar amount of dividends Pacific West Bank may pay depends upon its capital position and recent net income. Generally, if Pacific West Bank satisfies its regulatory capital requirements, it may make dividend payments up to the limits prescribed under state law and FDIC regulations.

As of [●][●], 2026 there were [●] outstanding FS Bancorp common shares held by approximately [●] shareholders of record. As of June [●], 2026, there were 2,707,530 outstanding Pacific West common shares held by approximately 112 holders of record. Pacific West has not paid any dividends to its shareholders.

THE SPECIAL MEETING OF PACIFIC WEST SHAREHOLDERS

This proxy statement/prospectus constitutes the proxy statement of Pacific West for use at the special meeting of Pacific West’s shareholders to be held on [●], [●] [●], 2026 at [●] a.m. Pacific Time, at the corporate offices of Pacific West located at 1300 SW Fifth Avenue, Suite 900, Portland, Oregon 97201, and any adjournments thereof.

At the special meeting, the shareholders of Pacific West will consider and vote upon (i) approval of the merger agreement; and (ii) approval of the adjournment proposal.

Pursuant to the merger agreement, Pacific West will merge with and into FS Bancorp, and Pacific West’s wholly owned subsidiary, Pacific West Bank, will merge with and into 1st Security Bank. We expect to complete the merger of Pacific West with and into FS Bancorp during the quarter ending September 30, 2026.

When we complete the merger, Pacific West shareholders will receive, at the election of the holder, subject to the allocation and proration procedures set forth in the merger agreement, either cash or FS Bancorp common shares as merger consideration for each Pacific West common share they own, as described in “The Merger Agreement—Consideration to be Received in the Merger” on page 47.

Pacific West has supplied all information contained in this proxy statement/prospectus with respect to Pacific West. FS Bancorp has supplied all information contained in this proxy statement/prospectus with respect to FS Bancorp.

This proxy statement/prospectus is first being provided to shareholders of Pacific West on or about [●][●], 2026.

Voting and Proxy Procedure

Shareholders Entitled to Vote.

The close of business on [●] [●], 2026 was the record date for determining Pacific West shareholders entitled to receive notice of and to vote at the special meeting. On the record date, there were [●] Pacific West common shares outstanding held by [●] holders of record. Pacific West has no other class of voting securities outstanding. Each holder of Pacific West common shares is entitled to one vote for each Pacific West common share in that holder’s name on Pacific West’s books as of the record date on any matter submitted to the vote of the Pacific West shareholders at the special meeting.

If you are a beneficial owner of Pacific West common shares held by a broker, bank or other nominee (i.e., in “street name”), you will need proof of ownership to be admitted to the special meeting. A recent brokerage statement or letter from a bank or broker are examples of proof of ownership. If you want to vote your Pacific West common shares held in street name in person at the special meeting, you will have to get a written proxy in your name from the broker, bank or other nominee who holds your shares.

Voting Your Shares.

Holders of record who receive this proxy statement/prospectus and proxy card from Pacific West’s transfer agent (Transfer Online, Inc.) can vote your shares using one of the following methods:

Beneficial owners who receive this proxy statement and proxy card from their broker, bank or other nominee can vote your shares using one of the following methods:

Votes submitted by internet or by telephone must be received by 11:59 p.m., Pacific Time, on [●] [●], 2026. Internet and telephone voting are available 24 hours a day, and if you use one of those methods, you do not need to return a proxy card.

You can also vote in person at the special meeting if you are a holder of record or a beneficial owner who has obtained a written proxy in your name from the broker, bank or other nominee who holds your shares, and submitting your voting instructions by any of the methods mentioned above will not affect your right to attend the special meeting and vote.

Quorum.

The presence, in person or by proxy, of at least a majority of the total number of outstanding Pacific West common shares entitled to vote is necessary to constitute a quorum at the special meeting. Abstentions and broker non-votes will be counted as shares present and entitled to vote at the special meeting for purposes of determining the existence of a quorum.

Proxies; Proxy Revocation Procedures.

The Pacific West board of directors is soliciting proxies so that each shareholder has the opportunity to vote on the merger agreement and any other proposal to be considered at the special meeting. When a proxy card is returned properly signed and dated, the shares represented thereby will be voted in accordance with the instructions on the proxy card. If a shareholder of record attends the special meeting and wishes to vote in person, he or she may vote by ballot. Where no instructions are indicated, proxies will be voted in accordance with the recommendations of the Pacific West board of directors. The board recommends a vote:

Pacific West shareholders may revoke a proxy at any time by: (i) sending written notice of revocation to the corporate secretary of Pacific West prior to the special meeting; (ii) executing and delivering a proxy for the special meeting bearing a later date; or (iii) attending the special meeting and voting in person. Attendance at the special meeting will not automatically revoke a proxy, but a shareholder in attendance may request a ballot and vote in person thereby revoking a prior granted proxy.

Written notices of revocation or other communications about revoking your proxy should be addressed to Pacific West Bancorp, Attn: Corporate Secretary, 2040 8^th Avenue, West Linn, Oregon 97068.

Proxies that do not provide the proxy holders with direction in voting on the merger agreement or with respect to the adjournment proposal will be voted in favor of the merger agreement and the adjournment proposal, in accordance with the recommendation of the board of directors of Pacific West. Pacific West shareholders who provide no instruction with respect to the merger agreement will not be eligible to assert dissenters’ rights.

Vote Required; Voting Agreements.

The approval of the merger agreement will require the affirmative vote, in person or by proxy, of a majority of the outstanding Pacific West common shares. The directors and executive officers of Pacific West and their affiliates hold approximately 25.6% of the outstanding shares entitled to vote.

All of the directors and executive officers of Pacific West have entered into voting agreements with FS Bancorp with respect to the Pacific West common shares they own, in which they have agreed, among other things, to vote, or cause to be voted, all of their Pacific West common shares in favor of the merger agreement. See the section entitled “The Merger Agreement—Voting Agreements” on page 60. Because approval of the merger agreement requires the affirmative vote of a majority of the outstanding Pacific West common shares, failure to vote, abstentions and broker non-votes will have the same effect as a vote against the merger agreement.

The adjournment proposal will be approved if a majority of the votes cast at the special meeting are voted in favor of the adjournment proposal. The failure to vote, abstentions and broker non-votes on the adjournment proposal will have no effect on such proposal.

Proxy Solicitation

The accompanying proxy is being solicited by the board of directors of Pacific West. Pacific West will bear the entire cost of solicitation of proxies from holders of its common shares. In addition to the solicitation of proxies by mail, certain officers, directors and employees of Pacific West, without extra remuneration, may also solicit proxies in person, by telephone, facsimile or otherwise. We also may engage a proxy solicitor to assist in obtaining votes or procuring a quorum, in which case we would pay a customary fee for those services. Pacific West will pay printing, postage and mailing costs of the proxy statement/prospectus. All other costs, including legal, accounting, and any proxy solicitor fees, shall be borne by the party incurring such costs.

Security Ownership of Management and Certain Beneficial Owners

The following table sets forth the beneficial ownership of Pacific West common shares as of June [●], 2026 by (i) each director of Pacific West, (ii) Pacific West’s executive officers, (iii) all directors and executive officers of Pacific West as a group, and (iv) each person or entity known by Pacific West to beneficially own more than 5% of the outstanding Pacific West common shares. Unless otherwise specified, the address of each listed shareholder is c/o Pacific West Bancorp, 2040 8^th Avenue, West Linn, Oregon 97068.

The percentage of beneficial ownership is calculated in relation to the 2,707,530 Pacific West common shares that were issued and outstanding as of June [●], 2026, which excludes shares of unvested restricted stock. Beneficial ownership is determined in accordance with the rules of the SEC, which generally attribute beneficial ownership of securities to persons who possess sole or shared voting or investment power with respect to those securities. Shares of Pacific West common shares subject to options that are currently exercisable or exercisable within 60 days of June [●], 2026 are deemed outstanding for purposes of computing the percentage ownership of the persons holding such options, but are not deemed outstanding for purposes of computing the percentage ownership of any other person. Unless otherwise indicated, and subject to the voting agreements entered into with FS Bancorp in connection with the merger (see “The Merger Agreement—Voting Agreements”), to Pacific West’s knowledge, the persons or entities identified in the table below have sole voting and investment power with respect to all shares shown as beneficially owned by them.

THE MERGER

General

The boards of directors of FS Bancorp and Pacific West have unanimously approved the merger agreement providing for the merger of Pacific West with and into FS Bancorp, with FS Bancorp being the surviving entity, and the merger of Pacific West Bank with and into 1st Security Bank, with 1st Security Bank being the surviving institution. We expect to complete the merger of Pacific West with and into FS Bancorp during the quarter ending September 30, 2026.

Background of the Merger

From time to time since its establishment in 2004, Pacific West Bank has explored various alternatives to expand its market share, customer and deposit base, and geographic footprint. Pacific West was established as the holding company for Pacific West Bank in 2023, and from time-to-time Pacific West has also considered opportunities for a business combination, acquisition or other strategic initiative. However, Pacific West’s size and market position has made growth difficult from both an organic and a strategic perspective. Further, Pacific West has weathered two significant economic downturns in 2008 and 2020 that caused challenges for community banks generally, and that particularly affected certain West Coast markets, including Pacific West’s Portland headquarters. In response to these events and to other political and geopolitical events, federal and state banking regulators adopted new and expanded regulations that had the effect, among other things, of significantly increasing both the cost and the level of management required to successfully operate while attempting to achieve and maintain compliance with these regulations.

Recognizing that ongoing operational and financial risks would continue to plague Pacific West for the foreseeable future, and that the Portland Metropolitan Area in particular continues to experience significant upheaval in terms of the business climate and other factors, the Pacific West board decided in June 2025 to initiate a process to explore potential business combinations that would maximize value for shareholders while focusing appropriately on Pacific West’s employees, customers and communities. As part of that process, Pacific West interviewed three investment banking firms, including Raymond James & Associates, Inc., which we refer to herein as Raymond James. Representatives of Raymond James met with the Pacific West board on August 5, 2025 to discuss the proposed engagement and a range of potential options and strategic partners. The alternatives discussed included the merits and risks of remaining independent, as compared to a potential merger with another community bank; a merger of equals with another similarly sized bank; a sale to a regional or national bank; or a sale of assets and assumption of deposits of Pacific West Bank to a credit union. The Pacific West board determined that Pacific West’s size, financial capacity and geographic market made it infeasible for Pacific West to acquire another institution. The board discussed two primary alternatives: a sale of operating assets and assumption of liabilities to a credit union, and a merger or other business combination with another Pacific Northwest community bank. Following the August 5, 2025 board meeting and consideration of the proposals from the three investment banking firms interviewed, the Pacific West board engaged Raymond James as its exclusive financial advisor on August 16, 2025, and engaged counsel for legal advice in connection with this process on August 8, 2025. Pacific West’s counsel, Marcus Williams, is now a partner of Kilpatrick Townsend & Stockton LLP, but at the time of his initial engagement was a partner with Buchalter, APC. Pacific West’s Chief Executive Officer, Jason Wessling, initially met with Mr. Williams on August 11, 2025, to obtain advice about the process, costs, benefits and risks accompanying both alternatives. Among the matters considered were the more involved regulatory approval process and relatively slower timing associated with a sale to a credit union, as well as higher legal costs and less advantageous tax treatment associated with an asset sale structure applicable to such a transaction. Following ongoing discussions among Raymond James, Buchalter and Pacific West’s executive management, these representatives made a further presentation to the Pacific West board, whereupon the board instructed management and the advisors to pursue a process that would permit active engagement with both banks and credit unions.

Pacific West established and populated a secure data site containing both detailed and high-level due diligence data during the week of August 11, 2025, with interested parties to receive staged access at various points in the process. Buchalter and Raymond James developed a form of nondisclosure agreement to be used in this process during the week of August 11, 2025, and beginning on August 17, 2025, Raymond James made initial inquiries of 46 parties, including 28 bank holding companies and 18 credit unions. FS Bancorp was one of the three bank holding companies submitting initial indications of interest. A total of nine of these parties, including FS Bancorp, executed nondisclosure agreements, and Raymond James delivered copies of a confidential information memorandum (CIM) to each of these parties during the week of August 26, 2025. After follow-up discussions and preliminary due diligence Pacific West received five indications of interest: three from banks and two from credit unions. The bank proposals included cash/stock consideration from FS Bancorp then valued at approximately $35.9 million; a cash/stock offer from a bank holding company identified as Bank Holding Company B valued at $35.2 million to $38.7 million; a stock offer from a bank holding company identified as Bank Holding Company C valued at $29.0 million, and cash offers from the credit unions in the amounts of $41.3 million from Credit Union A and $38.5 million from Credit Union B.

At a meeting on September 18, 2025, the Pacific West board met with management and with representatives of Buchalter and Raymond James to discuss the pending proposals. The Pacific West Board noted that, although the credit union proposals were generally higher than the bank proposals, those transactions would involve both “double-taxation” treatment (meaning that tax would be incurred at both the corporate level and the shareholder level) and significantly more complex and time-consuming regulatory approval and liquidation processes. At the conclusion of this meeting the board instructed Raymond James to seek clarification from Credit Union A, which responded on October 6, 2025, with a detailed letter of intent proposing an acquisition price of $41.3 million, representing, among other things, that Credit Union A had substantially completed its due diligence examination of Pacific West, subject only to “confirmatory diligence” on certain limited matters. After a follow-up meeting with the advisors on October 10, 2025, the Pacific West board entered into the proposed letter of intent with Credit Union A, which included a 45-day exclusivity period, expiring on November 24, 2025, during which the parties intended to negotiate a definitive agreement. Initial management discussions commenced on October 14, 2025, and counsel for Credit Union A submitted a draft purchase and assumption agreement to Buchalter on November 4, 2025.

Representatives of Raymond James and Buchalter met with the Pacific West board on October 16, November 10 and November 20, 2025, to update the board as to progress on negotiations with Credit Union A. Based on discussions with management and with the Pacific West board, Buchalter also sent a revised draft of the purchase and assumption agreement to Credit Union A’s counsel on or about November 10, 2025. Credit Union A had indicated in its previous discussions and in its proposed letter of intent that it had substantially completed its due diligence and that only “confirmatory diligence” remained as to certain limited items, suggesting that it did not expect to propose a significant pricing adjustment. However, during the week of November 17, 2025, Credit Union A indicated that it had discovered matters in its “confirmatory” due diligence that led it to reduce its proposed book value multiple from 1.2x to 1.1x, and hinted that additional price reductions and adjustments might be forthcoming. Pacific West did not agree with the stated basis for the reduction in the book value multiple. Of greater concern to the Pacific West board, when Credit Union A was asked on November 18, 2025 to confirm its final price, it was unable to commit even to its revised book value multiple. Further, Credit Union A had rejected substantially all of Pacific West’s proposed revisions to the purchase and assumption agreement. Taken together, these factors led the Pacific West board to question whether Credit Union A was committed to completing the proposed transaction on terms and at a price, that would be acceptable to Pacific West. At its meeting on November 19, 2025, the Pacific West board elected to discontinue discussions with Credit Union A upon the expiration of the exclusivity period on November 24, 2025 and directed Raymond James to begin contacting other prospective acquirors after that date to determine the level of interest from those candidates.

In response to this outreach, FS Bancorp submitted a renewed indication of interest, with FS Bancorp submitting an indicative proposal substantially as described in this proxy statement/prospectus. FS Bancorp, on February 2, 2026 reduced the original offer by $1.1 million based on Pacific West’s actual earnings performance and the results of due diligence on the loan portfolio. Recognizing the higher purchase price reflected in the FS Bancorp proposal, the Pacific West board approved management entering into the letter of intent proposed by FS Bancorp on December 1, 2025, which included a sixty-day exclusivity period expiring on January 31, 2026. Counsel for FS Bancorp sent Buchalter a draft of the merger agreement on January 2, 2026, and after a discussion with management and Raymond James, Buchalter submitted responsive comments on January 13, 2026. During the period between December 18, 2025, and February 18, 2026, counsel and advisors for Pacific West, at the direction of management, continued to negotiate the merger agreement and various ancillary agreements, and the advisors also participated in update calls with the Pacific West board on January 21, 2026, and February 19, 2026. Pacific West and FS Bancorp also executed an extension of the exclusivity period contemplated by the letter of intent on January 31, 2026, extending the exclusivity period for an additional thirty days, until March 2, 2026.

A “reverse due diligence” examination was also conducted by Pacific West’s management and advisors during the week of February 16, 2026, including an extended interview with FS Bancorp’s management on February 19, 2026. Final drafts and execution versions of the merger agreement and the other transaction documents were completed on February 20, 2026, and on February 25, 2026, the Pacific West board conducted a special meeting at which the board, among other things, received extensive briefing from Buchalter regarding the board’s fiduciary duties in the context of the transaction and regarding the terms of the merger agreement, and the attendant legal risks. Raymond James also addressed the board regarding the fairness, from a financial point of view, of the merger to Pacific West’s shareholders. Following these presentations the merger agreement was unanimously approved by the Pacific West board, and at which time the Pacific West board also agreed to recommend the approval of the merger agreement by Pacific West’s shareholders. The merger agreement was publicly announced after the close of securities markets on February 25, 2026.

Recommendation of the Pacific West Board of Directors and Reasons of Pacific West for the Merger

At the special meeting held on February 25, 2026, the Pacific West board of directors determined that the terms of the merger agreement were in the best interests of Pacific West and its shareholders. In the course of reaching this determination and related decision to approve the merger agreement, the Pacific West board of directors evaluated the merger and the merger agreement in consultation with the management of Pacific West and its financial advisor and legal counsel. In reaching its determination, the Pacific West board of directors considered a number of factors. Such factors also constituted the reasons that the Pacific West board of directors unanimously determined to approve the merger agreement and to recommend that Pacific West’s shareholders vote in favor of the merger agreement. Such reasons included the following:

The Board also considered a number of uncertainties and risks in its deliberations concerning the transactions contemplated by the merger agreement, including the following:

The foregoing discussion of the reasons that led the Pacific West board of directors to approve the merger agreement and recommend that Pacific West’s shareholders vote in favor of the merger agreement is not intended to be exhaustive, and may not describe all of the reasons considered by individual directors, but is believed to include all of the material reasons for the decision of the Pacific West board as a whole. In reaching its determination to approve the merger agreement and to recommend shareholder approval of the merger agreement, the Pacific West board of directors based its recommendation on the totality of the information presented to it and did not assign any relative or specific weights to the reasons or factors considered in reaching that determination. Individual directors may have given differing weights to different reasons and factors. After deliberating with respect to the merger with FS Bancorp, considering, among other things, the matters discussed above, the Pacific West board of directors unanimously approved the merger agreement with FS Bancorp as being in the best interests of Pacific West and its shareholders.

This summary of the reasoning of Pacific West’s board of directors and other information presented in this section is forward-looking in nature and, therefore, should be read in light of the factors discussed under the section entitled “Cautionary Statement Regarding Forward-Looking Statements.”

Opinion of Pacific West’s Financial Advisor

Pacific West engaged Raymond James as its financial advisor in connection with the merger. Pursuant to that engagement, the Pacific West board of directors requested that Raymond James evaluate the fairness, from a financial point of view, to the holders of Pacific West common shares of the per share amount to be received by such holders in the merger pursuant to the merger agreement.

At the February 25, 2026 meeting of the Pacific West board of directors, representatives of Raymond James rendered its opinion, which was subsequently confirmed in writing, as to the fairness, from a financial point of view and as of such date, to the holders of Pacific West common shares of the per share amount to be received in the merger pursuant to the merger agreement, based upon and subject to qualifications, assumptions, and other matters considered in connection with the preparation of its opinion.

The full text of the opinion, which describes the procedures followed, assumptions made, matters considered and qualifications and limitations on the review undertaken by Raymond James in preparing the opinion, is attached as Appendix B to this proxy statement/prospectus. You should read the opinion and the description of Raymond James’ opinion contained in this proxy statement/prospectus carefully and in their entirety.

Raymond James’ opinion speaks only as of the date of the opinion. The opinion does not reflect any developments that may have occurred or may occur after the date of the opinion and prior to the completion of the merger. The opinion was for the information of, and was directed to, the Pacific West board of directors (in its capacity as such) in connection with its consideration of the financial terms of the merger. The opinion does not constitute a recommendation to the Pacific West board of directors in connection with the merger, and it does not constitute a recommendation to any holder of Pacific West common shares as to how to vote on the merger agreement, which merger consideration to elect or any other matter. Raymond James’ opinion does not address the underlying business decision of Pacific West to engage in the merger or enter into the merger agreement, the form or structure of the merger, the relative merits of the merger as compared to any other alternative business strategies that might exist for Pacific West or the effect of any other transaction in which Pacific West might engage.

In connection with its review of the proposed merger and the preparation of its opinion, Raymond James, among other things:

With Pacific West’s consent, Raymond James assumed and relied upon the accuracy and completeness of all information supplied by or on behalf of Pacific West, or otherwise reviewed by or discussed with Raymond James, and Raymond James did not undertake any duty or responsibility to, nor did Raymond James, independently verify any of such information. Furthermore, Raymond James undertook no independent analysis of any potential or actual litigation, regulatory action, possible unasserted claims or other contingent liabilities, to which Pacific West or FS Bancorp is a party or may be subject, or of any governmental investigation of any possible unasserted claims or other contingent liabilities to which Pacific West or FS Bancorp is a party or may be subject. With Pacific West’s consent, Raymond James’ opinion made no assumption concerning, and therefore did not consider, the potential effects of any such litigation, claims or investigations or possible assertions. Raymond James did not make or obtain an independent appraisal of the assets or liabilities (contingent or otherwise) of Pacific West. With respect to the projections and any other information and data provided to or otherwise reviewed by or discussed with Raymond James, Raymond James, with Pacific West’s consent, assumed that the projections and such other information and data were reasonably prepared in good faith on bases reflecting the best currently available estimates and judgments of management of Pacific West, and Raymond James relied upon Pacific West to advise Raymond James promptly if any information previously provided became inaccurate or was required to be updated during the period of its review. Raymond James expressed no opinion with respect to the projections or the assumptions on which they were based. Based upon the terms specified in the merger agreement, Raymond James assumed that the merger would be treated as a reorganization under the provisions of Section 368(a) of the Code. Raymond James assumed that the final form of the merger agreement would be substantially similar to the draft merger agreement dated as of February 23, 2026 that Raymond James reviewed, and that the merger would be consummated in accordance with the terms of the merger agreement without waiver of or amendment to any of the conditions thereto. Furthermore, Raymond James assumed, in all respects material to its analysis, that the representations and warranties of each party contained in the merger agreement were true and correct and that each party will perform all of the covenants and agreements required to be performed by it under the merger agreement without being waived. Raymond James also relied upon and assumed, without independent verification, that (i) the merger would be consummated in a manner that complies in all respects with all applicable international, federal and state statutes, rules and regulations, and (ii) all governmental, regulatory or other consents and approvals necessary for the consummation of the merger would be obtained and that no delay, limitations, restrictions or conditions would be imposed or amendments, modifications or waivers made that would have an effect on the merger or Pacific West that would be material to its analyses or opinion.

Raymond James expressed no opinion as to the underlying business decision to effect the merger, the structure or tax consequences of the merger, or the availability or advisability of any alternatives to the merger. Raymond James provided advice to the Pacific West board of directors with respect to the proposed merger. Raymond James did not, however, recommend any specific amount of consideration or that any specific consideration constituted the only appropriate consideration for the merger. Raymond James’ opinion is limited to the fairness, from a financial point of view, of the per share amount to be received by the holders of Pacific West common shares. Raymond James expressed no opinion with respect to any other reasons (legal, business, or otherwise) that may have supported the decision of the Pacific West board of directors to approve or consummate the merger. Furthermore, no opinion, counsel or interpretation was intended by Raymond James on matters that require legal, accounting or tax advice. Raymond James assumed that such opinions, counsel or interpretations had been or would be obtained from appropriate professional sources. Furthermore, Raymond James relied, with the consent of Pacific West, on the fact that Pacific West was assisted by legal, accounting and tax advisors, and, with the consent of Pacific West, relied upon and assumed the accuracy and completeness of the assessments by Pacific West and its advisors, as to all legal, accounting and tax matters with respect to Pacific West and the merger.

In formulating its opinion, Raymond James considered only what it understood to be the consideration to be received by the holders of Pacific West common shares. For purposes of Raymond James’ opinion, and with Pacific West’s consent, Raymond James assumed the per share amount to be $12.61 based on the volume-weighted average trading price of FS Bancorp common stock on Nasdaq of $41.54 for the 10 trading days ending February 24, 2026. Raymond James did not consider, and its opinion did not address, the fairness of the amount or nature of any compensation to be paid or payable to any of the officers, directors or employees of Pacific West, or such class of persons, in connection with the merger whether relative to the consideration received by the holders of the Pacific West common shares or otherwise. Raymond James was not requested to opine as to, and its opinion did not express an opinion as to or otherwise address, among other things: (1) the fairness of the merger to the holders of any class of securities, creditors or other constituencies of Pacific West, or to any other party, except and only to the extent expressly set forth in the last sentence of its opinion or (2) the fairness of the merger to any one class or group of Pacific West’s or any other party’s security holders or other constituents vis-à-vis any other class or group of Pacific West’s or such other party’s security holders or other constituents (including, without limitation, the allocation of any consideration to be received in the merger amongst or within such classes or groups of security holders or other constituents). Raymond James expressed no opinion as to the impact of the merger on the solvency or viability of Pacific West or FS Bancorp or the ability of Pacific West or FS Bancorp to pay their respective obligations when they come due.

Material Financial Analyses

The following summarizes the material financial analyses reviewed by Raymond James with the Pacific West board of directors at its meeting on February 25, 2026, which material was considered by Raymond James in rendering its opinion. No company or transaction used in the analyses described below is identical or directly comparable to Pacific West or the merger.

Selected Companies Analysis. Raymond James reviewed certain data for selected companies with publicly-traded equity securities that it deemed to be relevant for its analysis. The selected group represents companies Raymond James believed to be relevant to Pacific West. Raymond James analyzed the relative valuation multiples of ten (10) publicly-traded financial institutions that met the following criteria: (i) traded over the NASDAQCM, NASDAQGM, NASDAQQS, NYSE, NYSEAM, OTCBB, OTCEM, OTCNO, OTCPK, OTCQB, or OTCQX stock exchanges; (ii) headquartered in Oregon or Washington; and (iii) had total assets between $100 million and $1.0 billion. This group excluded targets of announced mergers and institutions with a specialized or niche focus. The selected companies that Raymond James deemed relevant included the following:

Raymond James calculated various financial multiples for each selected company, including price per share at close on February 24, 2026 compared to (i) tangible book value, or TBV, per share at the most recently reported financial period ended December 31, 2025 or September 30, 2025 as shown by S&P Global Market Intelligence and (ii) last twelve months, or LTM, earnings per share for the most recent LTM financial period reported. Raymond James reviewed the high, 75^th percentile, mean, median, 25^th percentile, and low relative valuation multiples for each of the selected companies and compared them to the corresponding valuation multiples of the selected public companies and to the corresponding valuation multiples for Pacific West implied by the assumed per share amount. The results of the selected companies’ analysis are summarized below:

Furthermore, Raymond James applied the high, 75^th percentile, mean, median, 25^th percentile, and low relative valuation multiples for each of the metrics to Pacific West actual financial results for the 12 months ending December 31, 2025 to derive an implied per share amount. Raymond James then compared those implied values to $12.61, the value attributed to the per share amount for the purposes of Raymond James’ opinion. The results of this analysis are summarized below.

Selected Transactions Analysis. Raymond James analyzed publicly available information relating to selected national transactions announced since January 1, 2024 involving financial institution targets headquartered in the United States with total assets between $100 million and $1.0 billion, and an LTM Return on Average Assets less than 0.50%. These transactions excluded: (i) transactions without publicly disclosed deal value or sufficient financial information; (ii) mergers of equals; and (iii) transactions in which less than 100% of the target was acquired. The selected transactions (with transaction announcement dates shown) used in the analysis included:

Raymond James examined valuation multiples of transaction value compared to the target companies’ (i) most recent quarter TBV at announcement; (ii) LTM earnings at the time of announcement; and (iii) premium to core deposits (total deposits less time deposits greater than $100,000). Raymond James reviewed the high, 75th percentile, median, mean, 25th percentile, and low relative valuation multiples of the selected regional and national transactions.