UNITED STATES
SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

Proxy Statement Pursuant to Section 14(a) of

The Securities Exchange Act of 1934 (Amendment No.    )

Filed by the Registrant ☒

Filed by a Party other than the Registrant ☐

Check the appropriate box:

Westamerica Bancorporation

(Name of Registrant as Specified in Its Charter)

(Name of Person(s) Filing Proxy Statement, if other than the Registrant)

Payment of Filing Fee (Check the appropriate box):

1108 Fifth Avenue
San Rafael, California 94901

March 17, 202315, 2024

To Our Shareholders:

You are cordially invited to attend the Annual Meeting of Shareholders of Westamerica Bancorporation. It will be held at 10:00 a.m. Pacific Time on Thursday, April 27, 2023,25, 2024, at Westamerica Bancorporation, 4550 Mangels Blvd., Fairfield, California as stated in the formal notice accompanying this letter. We hope you will plan to attend.

At the Annual Meeting, the shareholders will be asked to (i) elect eight directors; (ii) approve a non-binding advisory vote on the compensation of our named executive officers; (iii) approve a non-binding advisory vote on the frequency of the advisory vote on the compensation of our named executive officers; (iv) ratify the selection of the independent auditor; and (v)(iv) conduct other business that may properly come before the Annual Meeting.

In order to ensure your shares are voted at the Annual Meeting, you can vote through the internet, by telephone or by mail. Instructions regarding internet and telephone voting are included on the Proxy Card. If you elect to vote by mail, please sign, date and return the Proxy Card in the accompanying postage-paid envelope. The Proxy Statement explains more about voting in the section entitled “Voting Information – How You Can Vote.”

We look forward to seeing you at the Annual Meeting.

	Sincerely,
	David L. Payne
	Chairman of the Board, President
	and Chief Executive Officer

WESTAMERICA BANCORPORATION

1108 Fifth Avenue

San Rafael, California 94901

NOTICE OF ANNUAL MEETING OF SHAREHOLDERS

Items of Business

Management’s eight nominees are listed and described in the attached proxy statement.

Who Can Vote?

Shareholders of record at the close of business on March 6, 2023,2024 are entitled to notice of, and to vote at, the Annual Meeting or any postponement or adjournment thereof.

Admission to the Annual Meeting

No ticket will be necessary for admission to the Annual Meeting. However, to facilitate the admission process, Shareholders of record planning to attend the Annual Meeting should check the appropriate box on the Proxy Card. Your name will be added to a list of attendees. If you hold shares through an intermediary, such as a bank or broker, you may need to register at the desk in the lobby. Please bring the following as evidence of ownership: 1) a legal proxy, or your brokerage statement dated on or after March 6, 2023,2024, evidencing your ownership on March 6, 2023,2024, the record date; and 2) photo identification.

Annual Report

Westamerica Bancorporation’s Annual Report on Form 10-K (“Annual Report”) to shareholders for the fiscal year ended December 31, 20222023 is enclosed or is available for viewing as indicated on the Shareholder Meeting Notice and on the Company’s website at: www.westamerica.com, under “Shareholders.” The Annual Report contains financial and other information about the activities of Westamerica Bancorporation, but does not constitute a part of the proxy soliciting materials.

	BY ORDER OF THE BOARD OF DIRECTORS
	Kris Irvine
March 17, 202315, 2024	VP/Corporate Secretary

Important notice regarding the availability of proxy materials for the shareholder meeting being held on

Thursday, April 27, 2023:25, 2024:

The Proxy Statement and the Annual Report on Form 10-K are available at: www.westamerica.com.

TABLE OF CONTENTS

WESTAMERICA BANCORPORATION

1108 Fifth Avenue

San Rafael, California 94901

___________

PROXY STATEMENT

March 17, 202315, 2024

___________

GENERAL

The Westamerica Board of Directors is soliciting proxies to be used at the 20232024 Annual Meeting of Shareholders of Westamerica Bancorporation (the “Company”), which will be held at 10:00 a.m. Pacific Time, Thursday, April 27, 2023,25, 2024, or at any adjournment or postponement of the Annual Meeting (collectively, the “Annual Meeting”). The Board of Directors is soliciting proxies to give all shareholders an opportunity to vote on matters to be presented at the Annual Meeting. In the following pages of this Proxy Statement you will find information on matters to be voted at the Annual Meeting.

Voting Information

Internet Availability of Proxy Materials. We are providing proxy materials to our shareholders primarily via the internet, instead of mailing printed copies of those materials to each shareholder. By doing so, we save costs and reduce the environmental impact of our Annual Meeting. On or about March 17, 2023,15, 2024, we mailed a Notice of Internet Availability of Proxy Materials (“Notice”) to certain of our shareholders. The Notice contains instructions about how to access our proxy materials and vote online or vote by telephone. If you would like to receive a paper copy of our proxy materials, please follow the instructions included in the Notice. If you previously chose to receive our proxy materials electronically, you will continue to receive access to these materials via email unless you elect otherwise.

Proof of Ownership May Be Required for Attending Annual Meeting in Person. You are entitled to attend the Annual Meeting only if you are a shareholder as of the close of business on March 6, 2023,2024, the record date, or hold a valid proxy for the meeting. In order to be admitted to the Annual Meeting, the Company reserves the right to request proof of ownership of Westamerica Bancorporation common stock on the record date. This can be:

Any holder of a proxy from a shareholder must present the Proxy Card properly executed, and a copy of the proof of ownership. The Company reserves the right to ask shareholders and proxy holders to present a form of photo identification such as a driver’s license.

Proxy Card. The proxies will vote the shares represented by proxies at the Annual Meeting. If you sign, date and return your Proxy Card but do not specify how to vote your shares, the proxies will vote FOR the election of all of the Director nominees, FOR approval of the advisory vote on the compensation of our named executive officers, for EVERY ONE YEAR on the frequency of the advisory vote on the compensation of our named executive officers, and FOR ratifying the selection of independent auditor. The proxies will also have discretionary authority to vote in accordance with their judgment on any other matter that may properly come before the Annual Meeting that we did

not have notice of by February 1, 2023.January 31, 2024. Management is not aware of any other business to come before the Annual

Meeting, and as of the date of this proxy statement, no shareholder has submitted to management any proposal to be acted upon at the Annual Meeting.

Quorum and Shares Outstanding. A quorum, which is a majority of the total shares outstanding as of the record date, must be present to hold the Annual Meeting. A quorum is calculated based on the number of shares represented by shareholders attending in person or by proxy. On the record date, March 6, 2023, 26,918,0022024, 26,677,701 shares of Westamerica Bancorporation common stock were outstanding. We also count broker non-votes, which we describe below, as shares present or represented at the Annual Meeting for the purpose of determining whether a quorum exists.

Election of Director Nominees. Each share is entitled to one vote, except in the election of Directors where a shareholder may cumulate votes as to candidates nominated prior to voting, but only if a shareholder gives notice of intent to cumulate votes prior to the voting at the Annual Meeting. If any shareholder gives such notice, all shareholders may cumulate their votes for nominees. Under cumulative voting, each share carries as many votes as the number of directors to be elected, and the shareholder may cast all of such votes for a single nominee or distribute them in any manner among as many nominees as desired. This Proxy Statement solicits the discretionary authority to cumulate votes and allocate them in the proxy holders’ discretion if any shareholder requests cumulative voting. In the election of directors, the eight nominees receiving the highest number of votes will be elected. If your proxy is marked “Withhold” with regard to the election of any nominee, your shares will be counted toward a quorum and for other nominees but they will not be voted for the election of that nominee.

Vote Required; Effect of Abstentions and Broker Non-Votes. The shares of a shareholder whose proxy on any or all proposals is marked as “Abstain” will be included in the number of shares present at the Annual Meeting to determine whether a quorum is present. If you are the beneficial holder of shares held by a broker or other custodian, you may instruct your broker how to vote your shares through the voting instruction provided by your broker or other custodian. If you wish to vote the shares you own beneficially at the meeting in person, you must first request and obtain a legal proxy from your broker or other custodian. If you choose not to provide instructions or a legal proxy, your shares are referred to as “uninstructed shares.” Whether your broker or custodian has the discretion to vote these shares on your behalf depends on the proposal. Brokers and custodians cannot vote uninstructed shares on your behalf in the election of directors or the advisory votes on executive compensation. For your vote to be counted on these matters, you must submit your voting instruction form to your broker or custodian.

The following table summarizes the votes required for passage of each proposal and the effect of abstentions and uninstructed shares held by brokers:

VotesAbstentions and nonvotes will have no effect on the outcome of the Proposal 1.Votes in favor of Proposals 2 and 43 must also constitute a majority of the required quorum for the meeting. IfTherefore, if votes in favor are less than a majority of the required quorum, abstentions and non-votes would have the effect of a vote against the proposal.

How You Can Vote. Your vote is very important and we hope that you will attend the Annual Meeting. However, whether or not you plan to attend the Annual Meeting, please vote by proxy.

Registered Holders.If your shares are registered directly in your name with the Company’s transfer agent, Computershare Investor Services, LLC, you are considered a registered holder of those shares. Please vote by proxy in accordance with the instructions on your Proxy Card, or the instruction you received by email.

A registered holder can vote in one of the following four ways:

Beneficial Shareholders.If your shares are held in a brokerage account in the name of your bank, broker, or other holder of record (“beneficial holder” or “street name”), you are not a registered holder, but rather are considered a beneficial holder of those shares. Your bank, broker, or other holder of record will send you instructions on how to vote your shares. If you are a beneficial holder, you must obtain a legal proxy, executed in your favor, from the holder of record to be able to vote in person at the Annual Meeting.

Voting Deadlines.Shareholders voting by telephone or internet must vote by 12:01 a.m. Central Time, on April 27, 202325, 2024 to ensure that their vote is counted. If you are a participant in the Westamerica Bancorporation Tax Deferred Savings/Retirement Plan (ESOP), however, your vote must be received by 11:59 p.m. Central Time, on April 24, 2023.15, 2024.

Revocation of Proxy.Registered holders who vote by proxy, whether by telephone, internet or mail, may revoke that proxy at any time before it is voted at the Annual Meeting. You may do this by: (a) signing another Proxy Card with a later date and delivering it to us prior to the Annual Meeting or sending a notice of revocation to the Corporate Secretary of Westamerica at 1108 Fifth Avenue, San Rafael, CA 94901; (b) voting at a later time by telephone or on the internet prior to 12:01 a.m. Central Time, on April 27, 202325, 2024 (prior to 11:59 p.m. Central Time, on April 24, 202315, 2024 for ESOP participants); or (c) attending the Annual Meeting in person and casting a ballot. If you are a beneficial holder, you may change your vote by submitting new voting instructions to your broker or other nominee.

Additional Information

Householding.As permitted by the Securities Exchange Act of 1934 (the “Exchange Act”) only one envelope containing two or more Notices of Internet Availability of Proxy Materials is being delivered to shareholders residing at the same address, unless such shareholders have notified their bank, broker, Computershare Investor Services, or other holder of record that they wish to receive separate mailings. If you are a beneficial holder and own your shares in street name, contact your broker, bank or other holder of record to discontinue householding

and receive your own separate copy of the Notice in future years. If you are a registered holder and own your shares through Computershare Investor Services, contact Computershare toll-free at 877-588-4258 or in writing directed to Computershare Investor Services, 150 Royall Street, Suite 101, Canton, MA 02021 to discontinue

householding and receive multiple Notices in future years. To receive an additional Annual Report or Proxy Statement this year, contact Shareholder Relations at 707-863-6992 or follow the instructions on the Notice. Mailing of dividends, dividend reinvestment statements, and special notices will not be affected by your election to discontinue duplicate mailings of the Notice.

Electronic Access to Proxy Materials and Annual Reports. Whether you received the Notice of Internet Availability of Proxy Materials or paper copies of proxy materials, this Proxy Statement and the 20222023 Annual Report are available on the Company’s website at: www.westamerica.com. If you hold your Westamerica Bancorporation common stock in street name through a broker, a bank or other nominee, you may have the option of securing your Proxy Statement and Annual Report via the internet. If you vote this year’s proxy electronically, you may also elect to receive future Proxy Statements, Annual Reports and other materials electronically by following the instructions given by your bank, broker, or other holder of record when you vote. Our website is available for information purposes only and should not be relied upon for investment purposes, nor is it incorporated by reference into this Proxy Statement.

Stock Ownership

Security Ownership of Certain Beneficial Holders.The following table sets forth information regarding shareholders beneficially holding more than 5% of Westamerica Bancorporation common stock outstanding as of December 31, 2022,March 6, 2024, based on information available to the Company, including filings made with the SEC.

⁽¹⁾ The Schedule 13G filed with the SEC on January 24, 2023,February 12, 2024, disclosed that at December 31, 2023, the reporting entity, American Century Investment Management, Inc., beneficially owned 1,455,759 shares as to which it held sole voting power over 1,419,087 shares and sole

dispositive power of 1,455,759. Of such shares, Stowers Institute for Medical Research reported beneficial ownership of 1,455,759 shares as to which it reported sole dispositive authority and 1,419,087 shares as to which it held sole voting power.

⁽²⁾ The Schedule 13G/A filed with the SEC on January 23, 2024, disclosed that as of December 31, 2023, the reporting entity, BlackRock, Inc., beneficially owned 3,902,878 shares as to which it held sole voting power over 3,759,2583,854,514 shares and sole dispositive power over 3,803,079all such shares.

⁽²⁾⁽³⁾ The Schedule 13G filed with the SEC on February 9, 2023,13, 2024, disclosed that as of December 31, 2023, the reporting entity, The Vanguard Group, Inc., held shared voting power over 29,51526,109 shares, sole dispositive power over 3,342,1443,437,148 and shared dispositive power over 55,50755,736 shares.

Security Ownership of Directors and Management.The following table shows the number of common shares and the percentage of the common shares beneficially owned (as defined below) by each of the current Directors, by the Chief Executive Officer (“CEO”), by the Chief Financial Officer (“CFO”), by the three other most highly compensated executive officers, and by all Directors and Officers of the Company as a group as of March 6, 2023. As of March 6, 2023, there were 26,918,002 outstanding shares of Westamerica Bancorporation’s common stock.2024. For the purpose of the disclosure of ownership of shares by Directors and officersOfficers below, shares are considered to be beneficially owned if a person, directly or indirectly, has or shares the power to vote or direct the voting of the shares, the power to dispose of or direct the disposition of the shares, or the right to acquire beneficial ownership of shares within 60 days of December 31, 2022.2023.

* Indicates beneficial ownership of less than one-tenth of one percent (0.1%) of the Company’s common shares.

** The address of all persons listed is 1108 Fifth Avenue, San Rafael, CA 94901.

⁽¹⁾ None of the shares held by the Directors and Officers listed above have been pledged.

⁽²⁾ In calculating the percentage of ownership, all shares which the identified person or persons have the right to acquire by exercise of options are deemed to be outstanding for the purpose of computing the percentage of the class owned by such person, but are not deemed to be outstanding for the purpose of computing the percentage of the class owned by any other person.

⁽³⁾ Ms. Belew was appointed Director October 26, 2023

⁽⁴⁾Shares held in trust as to which Mr. Bowler is co-trustee with shared voting and investment power.

⁽⁴⁾⁽⁵⁾ Includes 6,000Mr. Camsey was appointed Director February 22, 2024. Mr. Camsey has an indirect ownership by spouse of 86 shares held in a trust as to which Ms. MacMillan is trustee and 400 shares held in trust under the California Uniform Gift to Minors Act as to which Ms. MacMillan is custodian.with no voting or investment power.

⁽⁵⁾⁽⁶⁾ Includes 242,417 shares held directly or indirectly by a family trust of which Mr. Payne is the sole trustee with sole voting and investment power. Of such 772,707 shares, 528,837 shares are held by Gibson Radio and Publishing, which is 100% owned by such trust and for which Mr. Payne serves as President and CEO. Mr. Payne and members of his immediate family are among the beneficiaries of the trust. Mr. Payne disclaims beneficial ownership of the shares held directly or indirectly by the trust except to the extent of his pecuniary interest therein. Also includes 462 shares held in a trust under the California Uniform Gift to Minors Act as to which Mr. Payne is custodian.

⁽⁶⁾⁽⁷⁾ Includes 528,837 shares owned by Gibson Radio and Publishing Company, of which Mr. Payne is President and CEO, as to which Mr. Payne disclaims beneficial ownership, and 345,808 shares held in a trust as to which Mr. Payne is co-trustee with shared voting and investment power.

⁽⁷⁾⁽⁸⁾ Includes 13,799 shares held in a trust as to which Mr. Thorson is co-trustee with shared voting and investment power.

Delinquent Section 16(a) Reports

Section 16(a) of the Securities and Exchange Act requires the Company’s directors, executive officers, and persons who own more than ten percent of the Company’s common stock to file with the SEC initial reports of ownership, reports of changes in ownership of common stock of the Company, and to furnish the Company with copies of all Section 16(a) reports they file. Based solely upon a review of such reports and written representations that no other reports were required, the Company believes that all reports required by Section 16(a) of the Exchange Act to be filed by its executive officers and directors during the last fiscal year were filed on a timely basis except that⁽⁹⁾ Mr. Rizzardi failed to file two Form 4s on a timely basis, each reporting one transaction.Leavitt resigned from Westamerica, March 2023.

Anti-Hedging and Anti-Pledging Policy

The Company’s Insider Trading and Stock Hedging Policy prohibits our directors, executive officers, and other employees with access to material non-public information from engaging in transactions, that hedge or offset, or are designed to hedge or offset, any decrease in the market value of Company securities in which they have an economic interest. Prohibited transactions include but are not limited to: (1) selling short any Company common stock; and (2) buying or selling puts or calls or other derivatives on Company securities, or otherwise entering into any hedging arrangements involving Company securities.

PROPOSAL 1 – ELECTION OF DIRECTORS

Board of Directors

The Board has nominated eight candidates for election as Directors at the Annual Meeting to hold office until the next Annual Meeting or until their successors are elected and qualified. The proxies will vote for the eight nominees named below unless you give different voting instructions on your Proxy Card. Each nominee is presently a Director of the Company and has consented to serve a new term. The Board does not anticipate that

any of the nominees will be unavailable to serve as a Director, but if that should occur before the Annual Meeting, the Board reserves the right to substitute another person as nominee.nominee or reduce the number of directors to be elected. The proxies will vote for any substitute nominated by the Board of Directors. The proxies may use their discretion to cumulate votes for election of Directors and cast all of such votes for any one or more of the nominees, to the exclusion of the others, and in such order of preference as they may determine at their discretion.

Nominees

The nominees for election as Directors are named and certain information with respect to them is given below. Our nominees are seasoned leaders who bring to the Board an array of financial services, public and private company, non-profit,nonprofit, and other business experience. As a group they possess experience in leadership, consumer banking, commercial and small business banking, investment banking, capital markets, financial advisory services, finance and accounting, risk management and real estate. Many of the Board MembersDirectors have seen the Company through a variety of economic conditions. The information below has been furnished to the Company by the respective nominees. All of the nominees have engaged in their indicated principal occupation for more than five years, unless otherwise indicated and no nominee has served on the Board of Directors of another public company during the past five years. Each nominee is a current director of both the Company and its subsidiary, Westamerica Bank.Bank (the “Bank”).

Name of Nominees, Principal Occupations, and Qualifications

Alisa Belew – Director since 2023

Alisa Belew (40) is a Director and commercial real estate agent with Newmark in San Rafael, California. Ms. Belew is a member of the Loan and Investment Committee and the Employee Benefits and Compensation Committee. Ms. Belew was appointed to the Board in October 2023.

Ms. Belew joined Newmark in 2010 and specializes in leasing and sales of commercial properties in Marin and Sonoma counties. She is a dedicated, top performing real estate agent with a proven record of producing results for her clients. Ms. Belew advises clients on stabilization strategies and provides relevant market data. She prepares budgets, projections and competitive sets and advises on market trends. She specializes in managing the transaction process and all aspects of the marketing campaign, including preparing market reports, facilitating tours, contract negotiations, due diligence oversight and execution through the closing process. Ms. Belew is the fifth generation to teach Irish dancing through her family’s school, The Healy School of Irish Dance.

Alisa Belew’s extensive experience in commercial real estate, her understanding of business and her community involvement provide the board with in-depth knowledge of the market, especially in the North Bay.

E. Joseph Bowler – Director since 2003

E. Joseph Bowler (86)(87) retired as Senior Vice President and Treasurer of the Company in 2002. He currently serves as a member of the Audit Committee, and the Loan and Investment Committee and the Nominating Committee. Mr. Bowler holds a Masters of Business Administration from Stanford University.

With many years of direct banking experience, Mr. Bowler brings strong financial and investment expertise important to the oversight of our financial reporting and interest rate risk management. In addition, Mr. Bowler’s experience as a director and trustee of various non-profitnonprofit community and educational organizations brings strategic planning and corporate governance skills to the Board.

Martin Camsey – Director since 2024

Martin Camsey (63) was the Chief Financial Officer at O’Gara Coach Company from October 2020 to April 2022 and has over 35 years’ experience in the retail automobile business, including positions from Controller to Vice

President/CFO and board member. Prior to that, Mr. Camsey was with Price Waterhouse for five years. Mr. Camsey retired in 2022. Mr. Camsey is a member of the Audit Committee and the Employee Benefits and Compensation Committee. Mr. Camsey was appointed to the Board February 2024

Mr. Camsey is a member of the AICPA and California Society of CPA’s. Mr. Camsey earned a BS degree in Business Administration/Accounting from CSU Sacramento and is a Certified Public Accountant (inactive) in the State of California.Mr. Camsey has served on numerous nonprofit boards and organizations including: Junior Achievement, Salvation Army, Sacramento Children’s Museum, Stanford Home for Children, KVIE Public Television and Dignity Health Sacramento Service Area Hospital Community Board.

Martin Camsey’s education and background in finance and administration as well as operational responsibilities, both in retail business and nonprofit governance, provides the Board with financial expertise, management and entrepreneurial skills.

Melanie Martella Chiesa – Director since 2020

Melanie Martella Chiesa (56)(57) is an optometrist in private practice at Monte Vista Optometry in Turlock, California. Dr. Martella Chiesa is a memberChair of the Employee Benefits and Compensation Committee, anda member of the Loan and Investment Committee.Committee, and Compliance Commitee.

Dr. Martella Chiesa is a lifelong resident of Hughson, California where she is a partner in her family’s walnut and almond farming operations. She is an owner and board member of Martella Farms, Inc., Ag Commodities, Grower Direct Nut, Inc., ARK Development and Nutty Gourmet Nut Company. Dr. Martella Chiesa is a graduate of the University of California, Berkeley, where she received her Doctor of Optometry degree. Dr. Martella Chiesa also received Bachelor of Science degrees in food science and nutrition, functional biology and visual sciences.

Dr. Martella Chiesa is passionate about local community and philanthropy. She, along with her husband, founded the

Ciara Chiesa Circle of Hope Fund. Melanie is also a memberpast Director of the Stanislaus Community Foundation, chaired their Board, Executive Governance, and Scholarship Committee and servedcontinues to serve on the ExecutiveAsset Development and DevelopmentGovernance Committees. Dr. Martella Chiesa also servesserved as a trustee for the Gallo Center for the Arts.

Along with leadership and private business knowledge, Dr. Martella Chiesa brings to the Board an understanding of agriculture, healthcare, philanthropy and issues of the Central Valley of California, which is one of Westamerica Bank’s primary markets.

Michele Hassid – Director since 2019

Michele Hassid (60)(61) is Principal at Macias, Gini & O’Connell LLP, an accounting firm. Ms. Hassid serves as the Chair of the Audit Committee and is a member of the Compliance Committee, Executive Committee, and the ExecutiveNominating Committee. Ms. Hassid has been designated as an Audit Committee “financial expert.”

Ms. Hassid joined Eckhoff and Company in 1990, and served as Managing Partner from 2013 until 2022, when the Company merged into Macias, Gini & O’Connell LLP.

Ms. Hassid assists clients with financial and operational needs. Ms. Hassid graduated with honors from San Francisco State University with a B.A. in Accounting and is a graduate of the San Rafael Leadership Institute. She holds a CPA certificate and a CGMA certification.

Ms. Hassid has memberships with AICPA, CALCPA, is the Treasurer of the Marin Leadership Foundation and is a finance committee member for Congregation Ner Tamid in San Francisco.

Ms. Hassid’s background and education provides financial expertise and entrepreneurial skills.

Catherine Cope MacMillan – Director since 1985

Catherine Cope MacMillan (75) is a former owner of the Huntington Hotel in San Francisco and La Playa Hotel in Carmel-by-the-Sea. She is a member of the Loan and Investment Committee, Employee Benefits and Compensation Committee, and the Audit Committee. Ms. MacMillan previously owned and operated a prominent restaurant for nearly 20 years. She is a graduate of the University of California at Davis and Pacific McGeorge School of Law. She has also served in numerous leadership capacities for community organizations.

Ms. MacMillan’s experience in administration and operational aspects of various businesses and organizations provides the Board with sound leadership.

Ronald A. Nelson – Director since 1988

Ronald A. Nelson (80) was Executive Vice President of Charles M. Schulz Creative Associates through 1995. He serves as the Chair of the Employee Benefits and Compensation Committee, is a member of the Audit Committee, Compliance Committee, and Nominating Committee. Mr. Nelson has a background as a Certified Public Accountant and has been designated as an Audit Committee “financial expert.” He has been a resident of Sonoma County since 1970, which is one of Westamerica Bank’s primary markets and where he has been involved in business management, investment management, and the development of commercial real estate. He also served as a board member and Chairman of Santa Rosa Memorial Hospital, which is the area’s primary acute care hospital.

Mr. Nelson’s extensive business and financial expertise provides important oversight of our financial reporting and risk management.

David L. Payne – Director since 1984

David L. Payne (67)(68) is Chairman, President & CEO of Westamerica Bancorporation. He was appointed Chairman in 1988 and Chief Executive OfficerCEO in 1989. Mr. Payne is Chairman of the Executive Committee and is a member of the Compliance Committee. Mr. Payne is also Chairman, President & CEO of Westamerica Bank. He brings to the Board strong leadership and a vision for the future. He has a thorough knowledge of the banking industry, manages regulatory and business development issues, and has extensive financial and accounting expertise. Mr. Payne possesses excellent management, strategic development and business skills.

Since Mr. Payne’s appointment as Chairman of the Board, Westamerica’s dividends per share have risen twelve-foldthirteen-fold and capital levels have increased thirteen-fold.fifteen-fold. Total assets have increased more than 500% during his tenure and net income has risen by a multiple of 25.tenure. Return on equity was 15.2%18.1% for the year ended December 31, 2022.2023.

Mr. Payne has successfully negotiated and led the Company through many mergers including: John Muir National Bank, Napa Valley Bancorporation, PV Financial, CapitolBank – Sacramento, North Bay Bancorp, ValliCorp Holdings, First Counties Bank, Kerman State Bank, Redwood Empire Bancorp, County Bank, and Sonoma Valley Bank. Mr. Payne also manages his family printing, publishing and cable television business.

Edward B. Sylvester – Director since 1979

Edward Sylvester (86) (87) is a California registered civil engineer and founder of Sylvester Engineering and SCO Planning and Engineering. He currently provides pro bono technical services to non-profit organizations. Mr. Sylvester is a member of the Executive Committee, Chair of the Loan and Investment Committee, the Nominating Committee, and the Compliance Committee, and is a member of the Executive Committee, and serves as the Lead Independent Director of Westamerica Bancorporation. Mr. Sylvester is the board Chairman of Nevada County Broadcasters, which owns KNCO and STAR 94 radio stations. He currently provides pro bono technical services to nonprofit organizations and also serves as a board member of Sierra Nevada Memorial Hospital Foundation and was past president of the hospital board. Mr. Sylvester is a board member of the Nevada County Finance Authority and the President of the Friends of Banner Mountain board, promoting preservation of trails and fire-wise issues. Mr. Sylvester has previously served as Chairman of the California Transportation Commission, Chairman of the Nevada County Transportation Commission, Chairman of the Board of the Grass Valley Chamber of Commerce, President of the Grass Valley Rotary Club, Chairman and founder of the Nevada County Business Association, President of the Sierra Trailblazers Running Club, Chairman of the California Alliance for Advanced Transportation Systems and numerous advisory committees of the county and the city of Grass Valley on engineering and policy-related issues. Mr. Sylvester has completed 23 marathons around the world and was the 14th person in the world to complete marathons on all seven continents including Antarctica. Mr. Sylvester is an avid traveler and photographer, who has visited 114 countries to date, searching for new things to experience and photograph.

The depth of Mr. Sylvester’s experience gives him first-hand understanding of all the nuances of development and development funding, a current knowledge of the retail economy, and a state-wide perspective and experience in funding allocation. His long tenure on the Board brings a historical and long-term perspective while he remains current on financial issues with his continuing leadership role in the community and active management positions.

Inez Wondeh – Director since 2021

Inez Wondeh (55)(56) is the Chief Executive Officer at BASS Medical Group (“BASS”) in Walnut Creek, California.California and California Market President at BASS Privia Management Company of California, LLC. Ms. Wondeh is a member of the Audit Committee and Employee Benefits and Compensation Committee. Ms.

Inez Wondeh joined BASS in 2015 as the Chief Operating Officer. Ms. Wondeh has over 20 years of experience as a healthcare executive. Ms. Wondeh helped execute many of BASS’ growth strategy shifts, including increasing the company’s physician network. Ms. Wondeh provides visionary leadership that inspires the highest level of

performance in the financial and operation administration at BASS. Ms. Wondeh holds a Master of Public Administration and a Master of Business Administration from the University of San Francisco. Ms. Wondeh is the

founder of Ngozi Educational and Healthcare Foundation, a non-profitnonprofit dedicated to provide no-cost K-12 education and health services to rural Liberia, West African children.

Ms. Wondeh’s experience in finance, administration and strategic planning of various businesses provides the Board with exceptional leadership.

THE BOARD OF DIRECTORS RECOMMENDS ELECTION OF ALL NOMINEES

Board of Directors and Committees

Director Independence and Leadership StructureStructure. . The Board of Directors has considered whether any relationships or transactions related to a Director were inconsistent with a Director’s independence. Based on this review, the Board has determined that A. Belew, E.J. Bowler, M. MartellaCamsey, M. M. Chiesa, M. Hassid, C.C. MacMillan, R.A. Nelson, E.B. Sylvester, and I. Wondeh are “independent” Directors as defined in NASDAQ rules. Mr. Payne is not independent because he is an officer of the Company and the Bank.Bank.

Our Board has carefully considered the critical issue of Board leadership. In the context of risk management, the leadership of each Board committee primarily responsible for risk management is vested in an independent committee chair. With regard to the leadership of the meetings of the full Board, our Board of Directors has carefully evaluated whether the positions of Chairman and CEO should be separate or combined. Our Board believes that the most effective leadership structure for the Company at this time is to combine the responsibilities of the Chairman and CEO, a structure that has been successful since 1989. The combined positions avoid a duplication of efforts, enable decisive leadership, and ensure a clear accountability for the performance of the Company, a more rapid implementation of decisions, and a consistent vision. Given the size of our employee base and our level of assets relative to larger, more complex banking structures, our Company is particularly well suited to combine the Chairman and CEO functions. Furthermore, our named executive officers have an average tenure of 2532 years and do not require the substantial oversight needed by a less experienced team, which has allowed our Chairman and CEO to lead the Company through eleven acquisitions since 1992.

To ensure strong Board oversight seven of our eight Directors are, as noted above, independent as defined by NASDAQ. Only non-management directors sit on Board committees, with the exception of the Executive Committee and the Compliance Committee, and every non-management director sits on one or more of these Committees. All non-management directors meet at least four times a year outside the presence of the Chairman and CEO. The Board completes an annual board evaluation that is discussed by the Nominating Committee and presented to the full Board. Although the Board believes that it is more effective to have one person serve as the Chairman and CEO at this time, it also recognizes the importance of strong independent leadership on the Board, accordingly, the Board has established a strong, Independent Lead Director, Mr. Sylvester, who serves at least one year from the date of appointment and has the following clearly delineated and comprehensive duties:

The Board does not believe that the fact an Independent Lead Director does not preside over the normal Board meeting

business sessions limits the ability of the Board to have open exchanges of views, or to address any issues the Board chooses, independently of the Chairman.

The Board of Directors of the Company also serve as the Board of Directors of Westamerica Bank, and as such are well informed of bank operations through regular reports and discussions on the operations of the Bank. The Directors’ longevity with the Company has exposed them to a wide range of business cycles, which plays a critical role in managing the risk profile and profitability of the Company through the current economic environment.

Role of the Board of Directors in Risk Oversight. TheThe Board is also responsible for overseeing all aspects of management of the Company, including risk oversight, which is effected through all Board committees, but primarily through the Board’s Audit Committee. The Internal Audit Department reports directly to the Board’s Audit Committee. It presents its independently prepared company-wide annual risk assessment, its evaluation of Management’s prepared risk assessment and its audit plan incorporating the risk assessment, including the policies and procedures utilized to monitor and control such exposures, to the Board’s Audit Committee.

The internal loan review function reports directly to the Board’s Audit Committee. It reports ongoing evaluations of loan portfolios and the risk rating of individual loans using guidelines established by bank regulatory authorities, to the Board’s Audit Committee.

Meetings. The Company expects all Board members to attend all meetings, including the Annual Meeting of Shareholders, except for reasons of health or special circumstances. The Board met on nine days during 2022.2023. Every Director attended at least 75% of the aggregate of: (i) the Board meetings held during that period in which they served; and (ii) the total number of meetings of any Committee of the Board on which the Director served. Each individual who served on the Board of the Company on the date of the 20222023 Annual Meeting of Shareholders attended the meeting.

Committees of the Board

⁽¹⁾ Ms. Belew was appointed Director October 26, 2023.

⁽²⁾ Mr. Camsey was appointed Director February 22, 2024.

⁽³⁾ Dr. Martella Chiesa was appointed chair of the committee December 14, 2023.

Executive Committee. The Board delegates to the Executive Committee all powers and authority of the Board in the management of the business affairs of the Company between board meetings, which the Board is allowed to delegate under California law.

Audit Committee. The Board of Directors has determined that all members of the Audit Committee are independent, as that term is defined by applicable rules of NASDAQ for Audit Committee purposes. The Board has also designated Ms. Hassid and Mr. Nelson asis an “Audit Committee financial experts”expert” as defined by the rules of the SEC and has

determined that they areshe is “financially sophisticated” under NASDAQ rules. In concluding that Ms. Hassid and Mr. Nelson areis the Audit Committee financial experts,expert, the Board determined that theyshe possess:

Designation of a person (or persons) as an Audit Committee financial expert does not result in the person being deemed an expert for any purpose, including under Section 11 of the Securities Act of 1933. The designation does not impose on the person any duties, obligations or liability greater than those imposed on any other Audit Committee member or any other Director and does not affect the duties, obligations or liability of any other member of the Audit Committee or Board of Directors.

The Audit Committee provides independent, objective oversight of the integrity of the Company’s financial statements, the Company’s compliance with legal and regulatory requirements, the independence and performance of the Company’s independent auditor as it performs audit, review or attest services, and the Company’s internal audit and control function. It selects and retains the independent registered public accounting firm, and reviews the plan and the results of the auditing engagement. It acts pursuant to a written charter that was reaffirmed by the Board of Directors in January 20232024 and attached as Exhibit A to thethis Proxy Statement for the 2021 Annual Meeting of Shareholders.Statement.

Employee Benefits and Compensation Committee. The Employee Benefits and Compensation Committee of the Board of Directors (the “Compensation Committee”) is comprised solely of Directors who are not current or former employees of Westamerica or any of its affiliates. They are independent as defined by NASDAQ rules.

The Compensation Committee administers Westamerica Bancorporation’s equity incentive plan, Tax Deferred Savings and Retirement Plan, Deferred Profit Sharing Plan, Deferred Compensation Plan, and the Westamerica Bancorporation Deferral Plan. It administers the Company’s compensation programs and reviews and reports to the Board the compensation level for executive officers, including the CEO, of the Company and its subsidiaries and determines that compensation plans are balanced between financial results and prudent risk taking. The Compensation Committee determines annual corporate performance objectives for equity compensation and cash bonuses and their related corporate, divisional and individual goals. Based on the CEO’s assessment of the extent to which each executive officer met those objectives and goals, the Committee determines each executive officer’s annual equity compensation and cash bonus. The Compensation Committee also establishes the individual goals and targets for the CEO. All compensation approved by the Compensation Committee is reported to the full Board of Directors.

The role of the Compensation Committee is described in greater detail under the section entitled “Compensation Discussion and Analysis.”

The Compensation Committee is governed by a written charter as required by NASDAQ rules. The charter was reaffirmed by the Board of Directors in January 20232024 and is attached as Exhibit A to the Proxy Statement for thisthe 2023

Annual Meeting of Shareholders. The Compensation Committee has the authority to seek assistance from officers and employees of the Company as well as external legal, accounting and other advisors. It has not retained outside

consultants for compensation advice, but can request assistance on an as-needed basis. It does not delegate authority to anyone outside of the Compensation Committee. The Payroll and Employee Benefits Department supports the Compensation Committee by fulfilling certain administrative duties regarding the compensation programs.

Nominating Committee.The Board of Directors has determined that all members of the Nominating Committee are independent, as defined in NASDAQ rules.

The Nominating Committee screens and recommends qualified candidates for Board membership. This Committee recommends a slate of nominees for each Annual Meeting. As part of that process, it evaluates and considers all candidates submitted by shareholders in accordance with the Company’s Bylaws, and considers each existing Board member’s contributions. The Committee also considers recommendations of shareholders. The Committee applies the same evaluation standards whether the candidate was recommended by a shareholder or the Board. The Nominating Committee is governed by a written charter, which was reaffirmed by the Board of Directors in January 20232024 and attached as Exhibit A to the Proxy Statement for the 2022 Annual Meeting of Shareholders.

While the Board does not have a formal diversity policy, it broadly defines diversity to encompass a range of skills and expertise sufficient to provide prudent guidance to the Company. In addition to the qualifications and characteristics described below, it considers whether the potential Director assists in achieving a mix of Board members that represents a diversity of background, perspective, and experience. Our Board includes Directors with experience in public corporations and non-profitnonprofit organizations, as well as entrepreneurial individuals who have successfully run their own private enterprise. Our Board also has a broad set of skills necessary for providing oversight to a financial institution, which includes proven leadership, and expertise in capital management, finance, accounting, regulatory affairs, and investment management.

Compliance Committee. The Committee provides oversight of the Company’s Compliance Management System to ensure compliance with consumer protection laws and regulations.

Board Diversity. The table below provides certain highlights of the composition of our board members and nominees. Each of the categories listed in the below table has the meaning as it is used in Nasdaq Rule 5605(f):

Nominating Directors. The Nominating Committee will consider shareholderShareholder nominations submittedmust be made in accordance with Section 2.14 of the Bylaws of the Company. That section requires, among other things, that nominations be submitted in writing and must be received by the Corporate Secretary at least 45not earlier than 120 days and not later than 90 days before the anniversary of the date on which the Company first mailed its proxy materials forof the prior year’s Annual Meeting of Shareholders. If the date for the current year’s Annual Meeting changes more than 30 days from the date on which the prior year’s meeting was held, the Company must receive notice with a reasonable amountnot earlier than 120 days prior to such Annual Meeting and not later than 90 days before such annual meeting or the 10th day following the day on which public announcement of time before the Company mails its proxy materials fordate of such meeting is first made by the current year.corporation. In addition, to comply with the SEC’s universal proxy rules, shareholders who intend to solicit proxies in support of nominees other than the Company’s nominees must provide notice setting forth the information required by SEC Rule 14a-19 no later than February 27, 2024,January 31, 2025, or such earlier date as may be required by the Company’s Bylaws. The nominating shareholder (or a qualified representative) and the nominating shareholder’s candidate(s) must be present in person at the meeting for the election of directors.

Nominations must include the following information:

The Committee has specified the following minimum qualifications it believes must be met by a nominee for a position on the Board:

Loan and Investment Committee. This Committee reviews major loans and investment policies.

Director Compensation

The following table and footnotes provide information regarding the compensation paid to the Company’s non-employee Directors in the year 2022.2023. Directors who are employees of the Company receive no compensation for their services as Directors.

⁽¹⁾ Non-employee Directors did not receive options or stock awards in 20222023 and none hold any options or stock awards. During 2022,2023, non-employee Directors of the Company were paid an annual retainer of $22,000. Each non-employee Director received $1,200 for each meeting of the Board attended and $600 for each Committee meeting attended. The Chairman of each Committee received an additional $250 for each Committee meeting attended. All non-employee Directors are reimbursed for expenses incurred in attending Board and Committee meetings. The Chairman of the Board, David L. Payne, is compensated as an employee and did not receive any compensation as a Director.

⁽²⁾ The Deferred Compensation Plan allows non-employee Directors to defer some or all of their Director compensation with interest earnings credited on deferred compensation accounts. The amount shown is the interest on nonqualified deferred compensation that exceeds 120% of the long-term Applicable Federal Rate, with compounding, on all cash compensation deferred in 20222023 and in previous years.

⁽³⁾ Mr. Bartolini did not stand for re-election in 2022.Ms. Belew was appointed Director October 26, 2023.

Westamerica Bancorporation does not have a charitable donations program for Directors nor does it make donations on behalf of any Director(s). The Company may make a nominal donation through its Community Relations program to non-profit organizations where a Director(s) may have an affiliation.⁽⁴⁾ Ms. MacMillan and Mr. Nelson resigned from the Board in 2023.

EXECUTIVE COMPENSATION

Executive Officers

The executive officers of the Company and Westamerica Bank serve at the pleasure of the Board of Directors and are subject to annual appointment by the Board at its first meeting following the Annual Meeting of Shareholders. It is anticipated that each of the executive officers listed below will be appointed to serve in such capacities at that meeting.

David L. Payne – Held since 1984

David L. Payne (67)(68) is the Chairman of the Board, President and CEO of the Company and Westamerica Bank. Mr. Payne also manages his family printing, publishing and cable television business. For additional information regarding Mr. Payne, please see “Proposal 1 – Election of Directors - Board of Directors” above.

John “Robert” A. Thorson – Held since 2023

Jesse Leavitt – Held since 2020

Jesse Leavitt (37)John “Robert” Thorson (63) is Senior Vice President and Chief Financial Officer of the Company. Mr. Leavitt is a California licensed certified public accountant. He held the position of Vice President and Controller upon joining the Company in March 2019 until December 2019. Prior to joining the Company, Mr. Leavitt was a bank examiner with the Federal Deposit Insurance Corporation from 2011 until 2016 and was Assistant Controller at Golden 1 Credit Union from 2016 until 2019.

John “Robert” Thorson – Held since 2020

John “Robert” Thorson (62) is Senior Vice President and Treasury Division Manager for the Company. Mr. Thorson joined Westamerica Bancorporation in 1989, was Vice President and Manager of Human Resources from 1995 until

2001, was Senior Vice President and Treasurer from 2002 untilthrough 2005 and 2020 through 2022, and was Senior Vice President and Chief Financial Officer from 2005 untilthrough 2019. He was reappointed as Chief Financial Officer in March 2023.

Brian Donohoe – Held since 2019

Brian Donohoe (41)(42) is Senior Vice President and Manager of Operations and System Administration of Community Banker Service Corporation, a subsidiary of Westamerica Bank. Mr. Donohoe joined Westamerica Bancorporation in 1999 and has held a variety of positions in the Banking Division and the Operations and Systems Division, most recently, Vice President and Manager of Business Services until 2018.

Russell W. Rizzardi – Held since 2008

Russell W. Rizzardi (67)(68) is Senior Vice President and Chief Credit Administrator of Westamerica Bank. Mr. Rizzardi joined Westamerica Bank in 2007. He has been in the banking industry since 1979 and was previously with Wells Fargo Bank and U.S. Bank.

Robert Baker – Held since 1995

Robert Baker (59) is Regional Vice President, Senior Regional Market Manager of Westamerica Bank. Mr. Baker joined Westamerica Bank in 1995 through the Bank’s acquisition of Pacific Valley National Bank. He later served as Senior Vice President, Sales and Marketing Director with County Bank and rejoined Westamerica in 2009. He has been in the banking industry since 1985 and has held various positions in branch banking, lending and marketing.

Code of Ethics. The Company has adopted a Code of Ethics (as defined in Item 406 of Regulation S-K of the Securities Act of 1933) that is applicable to its senior financial officers including its chief executive officer, chief financial officer, and principal accounting officer.

Compensation Discussion and Analysis

The executive compensation practices described below have been followed consistently for thirty years. At each Annual Meeting of Shareholders since 2010, a majority of our shareholders approved an advisory proposal on the Company’s executive compensation. Last year 9188 percent of the shares voting on this proposal voted to support our Corporation’s executive compensation strategy.

The Compensation Committee governs the executive compensation program that combines three compensation elements: base salary, annual non-equity cash incentives, and long-term stock grants. Several compensation philosophies and practices underlie this program:

In February 2013, the Board of Directors adopted a clawback policy that requires executive officers to forfeit previously awarded incentive compensation if the incentives were based on materially inaccurate financial statements or other performance measures that are later proven to be materially inaccurate or the achievement of which were due

to fraud or other misconduct. The Company’s 2019 Westamerica Omnibus Plan includes a clawback provision with similar terms. In October 2023, the clawback policy was revised to comply with new NASDAQ listing standards.

Establishing Incentive Levels, Determining Objectives and Measuring Performance. In administering the executive compensation program, the Compensation Committee determines “target” incentives for each position annually. The Compensation Committee exercises discretion in establishing “target” incentives in an effort to provide competitive pay practices while motivating and rewarding performance that benefits the Company’s long-term financial performance and shareholder interests, and avoids excessive risk-taking.

At the beginning of each calendar year, the Compensation Committee establishes annual corporate performance objectives. In establishing corporate performance objectives, the Compensation Committee takes into consideration the current operating environment for the commercial banking industry as well as internal management policies and practices which would, in the Compensation Committee’s opinion, benefit the long-term interests of the Company and its shareholders. Corporate performance measures include risk management elements considered to be responsive to the impact that current operating conditions could have on the long-term performance of the Company. The Compensation Committee monitors the economy and the banking industry’s operating environment throughout the ensuing year, and may exercise discretion in adjusting corporate performance objectives during the year.

The operating environment for the commercial banking industry is impacted by a myriad of factors including, but not limited to, local, national and global economic conditions, interest rate levels and trends, monetary policies of the Federal Reserve Board and its counterparts in other countries, fiscal policies of the United States government and other global political conditions, regulations and legislation, liquidity in capital markets, the demand for capital by commercial enterprises and consumers, new financial products, competitive response to changing conditions within the industry, trade balances, the changing values of real estate, currencies, commodities and other assets, and other factors.

Management policies and practices the Board considers in establishing corporate performance objectives include, but are not limited to, management of the Company’s balance sheet and product pricing in a manner which will benefit the long-term financial interests of shareholders, the type and variety of financial products and services offered by the Company, adherence to internal controls, management of the credit risk of the Company’s loan and investmentbond portfolios, management of liquidity to meet depository customer needs, the results of internal, regulatory and external audits, service quality delivered to the Company’s customers, service quality of “back office” support departments provided to those offices and departments directly delivering products and services to the Company’s customers, maintenance of operating policies and procedures which remain appropriate for risk management in a dynamic environment, timely and efficient integration of any acquired companies, operational efficiencies, and capital management practices.

Restricted performance shares (“RPS”) are restricted stock unit awards that vest upon the achievement of performance objectives established by the Compensation Committee. Historically, the Company has granted RPS awards to its executives with a three-year vesting period and vesting conditions based on performance factors including the Company’s three year cumulative diluted earnings per share (EPS), three year average of annual return on average total assets (ROA); three year average of annual return on average shareholders’ equity relative to industry average ROE (ROE differential); non-performing assets to total assets (NPA); and the efficiency ratio over three years.

In addition to establishing corporate performance objectives, the Compensation Committee also establishes individual goals for the CEO. In regard to the other executives named in the accompanying tables, the CEO recommends

divisional and individual performance objectives to the Compensation Committee, which considers, discusses, adjusts as necessary, and adopts such performance objectives.

Upon the closure of each calendar year, the Compensation Committee reviews corporate, divisional, and individual performance against the performance objectives for the year just completed. After thorough review and deliberation, the Compensation Committee determines the recommended amount of individual non-equity cash incentives and stock-based incentive awards. The Compensation Committee reports such incentives to the Board of Directors. Meetings of the Compensation Committee and Board of Directors routinely occur in January, immediately following the closure of the calendar year for which performance is measured for incentive compensation purposes.

Equity Compensation Plans. Long-term stock grants may only be awarded under shareholder approved stock-based incentive compensation plans (the “equity incentive plans”).

In 2019, the Company’s shareholders approved the 2019 Westamerica Omnibus Plan (the “2019 Plan”). The 2019 Plan authorizedauthorizes the grant of up to 1,235,898 shares (plus shares that become available if awards under prior plans expire unexercised or are cancelled, forfeited or terminated before being exercised). In addition, the 2019 Plan authorizedauthorizes the issuance of shares under an award granted in the assumption of, or in substitution for, outstanding awards previously granted by another business entity acquired by the Company. Any additional authorization of shares available for issuance must be approved by shareholders. The 2019 Plan expires on April 25, 2029, after which shareholder approval is again required to extend the term or approve a new equity incentive plan.

The 2019 Plan replaced the Company’s 2012 Amended and Restated Stock Option Plan of 1995 (the “2012 Amended Plan”). The Company may no longer grant any awards under the 2012 Amended Plan, though awards previously issued under such plan continue to be outstanding, subject to the terms of the applicable awards agreements. The 2012 Amended Plan established governing terms and conditions for all stock grants awarded from the effective date of the plan through the effective date of the 2019 Plan.

The 2019 Plan allows the following types of stock-based compensation awards:

Incentive Stock Options (“ISO”) allow the optionee to buy a certain number of shares of Westamerica Bancorporation common stock at a fixed price, which is established on the date of the option grant. ISOs are intended to meet the requirements of Section 422 of the Internal Revenue Code which provide advantages if certain conditions are met. If the optionee holds the acquired stock for the designated holding period, the optionee defers the timing of recognizing taxable income related to exercising the ISO. If the optionee complies with the ISO requirements, the Company does not receive a corporate tax deduction related to the shares issued.

Nonqualified Stock Options (“NQSO”) also give the optionee the option to buy a certain number of shares of Westamerica Bancorporation common stock at a fixed price, which is established on the date of grant. Unlike ISOs, NQSOs do not allow deferral of taxable income for the optionee. At the time NQSOs are exercised, the optionee incurs taxable income equal to the spread between the exercise price and the market price of the stock, and the Company receives a corporate tax deduction in the same amount.amount.

Share Appreciation Rights (“SAR”) provide the holder a cash payment equal to the difference between the fair market value of the Westamerica Bancorporation’sBancorporation common stock on the date the SAR is surrendered and the fair market value of the Company’s common stock on the date the SAR was granted. The optionee incurs taxable income at the time the SAR is settled and the Company receives a corporate tax deduction in the same amount.

Restricted Shares and Restricted Stock Units. The Compensation Committee determines the vesting schedule and performance goals, if any, applicable to the grant of restricted shares and Restricted Stock Units. Restricted Stock Units are awards that may be settled in Westamerica Bancorporation’sBancorporation common stock or cash, subject to vesting. As

described above, the Company has historically granted Restricted Stock Units as RPS awards that settle in shares of Westamerica Bancorporation’sBancorporation common stock, subject to the achievement of performance objectives. Award recipients receive shares at the end of the performance measurement period only if performance objectives are achieved. The award recipient incurs taxable income at the time any RPS vests and the Company receives a corporate tax deduction in the same amount.

Determination of Awards to Grant. In determining which type of stock-based compensation awards to grant, the Compensation Committee considers the attributes of each form of incentive. Examples include the ability to motivate management to make decisions based on the long-term interests of shareholders, the desire to compensate with shares rather than cash, and the tax consequences of each type of award. The Compensation Committee retains the latitude to utilize all forms of incentives provided under the equity incentive plans. In the current and preceding years, the Compensation Committee has utilized NQSO and RPS based on the motivational aspects of stock price appreciation, the settlement in shares rather than cash, and the preservation of tax deductions for the Company. As of March 6, 2023,2024, the Company had no ISO SAR or restricted stockSAR awards outstanding.

Determination of Exercise Price. The equity incentive plans require the exercise price of each NQSO, ISO or SAR to be no less than one hundred percent (100%) of the fair market value of the Company’sWestamerica Bancorporation common stock on the date of grant. The equity incentive plans do not allow re-pricing stock options for poor stock price performance.

Stock-based compensation awards are submitted by the Compensation Committee to the full Board of Directors for review. As described above, these meetings have routinely occurred in January immediately following the closure of the calendar year for which performance is measured for incentive compensation purposes. The Compensation Committee meeting has routinely been held during the same week as the related Board of Directors meeting. These January meetings follow by no more than ten business days the Company’s public disclosure of its financial results for the preceding year. As a result, stock option grants are awarded, and the exercise price of such grants are determined at a time when the Company has broadly disseminated its financial condition and current operating results to the public. The Company’s outstanding stock option grants are dated, and related stock option exercise prices are determined, on the January date the Compensation Committee meets to approve such grants.

Long-Term Incentive Attributes.The Board of Directors has designated the Compensation Committee as the administrator of the equity incentive plans. The Compensation Committee reports to the Board the terms and conditions of awards granted under these plans. In carrying out this responsibility, the Compensation Committee designs such awards as long-term incentives. The terms and conditions of currently outstanding awards under the Company’s several equity incentive plans include:

Compensation for the Chairman, President & CEO.Mr. Payne performs two functions for the Company. These two functions tend to be compensated separately at similarly sized banking institutions. Mr. Payne serves as Chairman of the Board with responsibilities including oversight of the organization and external strategic initiatives. Mr. Payne

also serves as President and CEO with responsibilities including daily management of internal operations. Mr. Payne’s total compensation reflects these broad responsibilities. Consistent with the overall compensation philosophy for

senior executives, Mr. Payne’s compensation has a greater amount of pay at risk through incentives than through base salary. Since Mr. Payne is compensated as an executive, he is not eligible to receive compensation as a Director.

As noted on page 3134 of this Proxy Statement under the Pension Benefits Table, during 1997 the Company entered into a nonqualified pension agreement (“Pension Agreement”) with Mr. Payne in consideration of Mr. Payne’s agreement that RPS awards granted in 1995, 1996 and 1997 would be cancelled.⁽¹⁾ In entering the Pension Agreement, the Board of Directors considered the following:

Compensation Awarded to Named Executive Officers. Base salaries for participants in the executive compensation program are generally limited to foster an environment where incentive compensation motivates and rewards corporate, divisional, and individual performance. As such, base pay increases are generally infrequent and limited to “control points” assigned to each position. The non-equity cash incentive formula has the following components:

In structuring performance goals for the named executive officers, the Compensation Committee emphasizes goals, which if achieved, will benefit the overall Company. As such, senior management level positions have high relative weighting on corporate objectives, and divisional leadership positions also have significant weighting on divisional objectives. The “target” cash incentive and the weighting of goals for the named executive officers for 20222023 performance were as follows:

⁽¹⁾The value of the surrendered RPS shares and the Pension Agreement were considered equivalent based on actuarial assumptions.

The Compensation Committee establishes corporate goals with the intent to balance current profitability with long-term stability of the Company and its future earnings potential. The 20222023 corporate performance goals related to current year “profitability” included return on average equity, return on average assets and diluted earnings per share. The performance goals designed to maintain the long-term stability of the Company include “quality” and “control” components. The “quality” measures include loan portfolio quality measures (classified loans and other real estate owned, non-performing loans and other real estate owned, and net loan losses to average loans) and service quality measures (service quality of support departments and branches). The “control” measures include annual non-interest expense to annual revenues (efficiency ratio), the level of annual non-interest expenses, and internal audit results. By maintaining both current year “profitability” goals and longer-term “quality” and “control” goals, Management has a disincentive to maximize current earnings at the expense of longer-term results.

At the beginning of the year, the Compensation Committee’s expectations for the 20222023 operating environment included uncertain economic growth, given the pandemicemployment conditions and relatively lowmonetary policy, sustainability of fiscal stimulus influences over deposit volumes, and evolution of interest rates.rate levels. The Committee reserved the ability to exercise a certain degree of judgment in adjusting target goals based on the ultimate operating environment.

The Compensation Committee determined the 20222023 operating environment was generally characterized as follows:

The Compensation Committee considered Management’s response to the current operating environment including:

The Compensation Committee exercised judgement by making adjustments to actual results to take into account the impact of the operating environment. Adjusted actual results against “target” performance goals were:

In reviewing the operating environment, Management’s response to the operating environment, and adjusted results compared to “target” performance goals, the Compensation Committee determined corporate performance to be 116%114%

of target goals.

As described above, divisional and individual goals are used in conjunction with corporate performance goals to determine cash bonus awards.

In addition to daily management responsibilities, Mr. Payne’s individual goals included:

Based on individual performance against these goals, the Committee exercised its discretion and assigned Mr. Payne a composite corporate and individual performance level of 94%103%.

In addition to routine on-going divisional responsibilities, Mr. LeavittThorson managed the Finance Divisionand Treasury Divisions toward functional goals, which included:

Based on the Finance Division’s results, the Committee determined divisional performance to be 106%.

In addition to daily management responsibilities, Mr. Leavitt’s individual goals included:

Based on individual performance against these goals, the Committee determined Mr. Leavitt’s individual performance to be 119%. As a result Mr. Leavitt’s composite corporate, divisional and individual performance level was 114%.

In addition to routine on-going divisional responsibilities, Mr. Thorson managed the Treasury Division toward functional goals, which included:

Based on the Finance and Treasury Division’sDivisions’ results, the Committee determined divisional performance to be 130%129%.

In addition to daily management responsibilities, Mr. Thorson’s individual goals included:included:

Based on individual performance against these goals, the Committee determined Mr. Thorson’s individual performance to be 150%. As a result, Mr. Thorson’s composite corporate, divisional and individual performance level was 126%125%.

In addition to routine on-going divisional responsibilities, Mr. Donohoe managed the Operations & Systems Division toward functional goals, which included:

Based on the Operations & Systems Division’s results, the Committee determined divisional performance to be 118%115%.

In addition to daily management responsibilities, Mr. Donohoe’s individual goals included:

Based on individual performance against these goals, the Committee determined Mr. Donohoe’s individual performance to be 138%. As a result, Mr. Donohoe’s composite corporate, divisional and individual performance level was 121%119%.

In addition to routine on-going divisional responsibilities, Mr. Rizzardi managed the Credit Division toward functional goals, which included:

Based on the Credit Division’s results, the Committee determined divisional performance to be 96%101%.

In addition to daily management responsibilities, Mr. Rizzardi’s individual goals included:

Based on individual performance against these goals, the Committee determined Mr. Rizzardi’s individual performance to be 96%99%. As a result, Mr. Rizzardi’s composite corporate, divisional and individual performance level was 107%108%.

In addition to routine on-going divisional responsibilities, Mr. Baker managed the Banking Division toward functional goals, which included:

Based on the Banking Division’s results, the Committee determined divisional performance to be 100%.

In addition to daily management responsibilities, Mr. Baker’s individual goals included:

Based on individual performance against these goals, the Committee determined Baker’s individual performance to be 138%. As a result, Mr. Baker’s composite corporate, divisional and individual performance level was 111%.

Based on the above described performance against objectives, the Committee determined cash incentive awards as follows:

The size of stock grants is determined by corporate performance using stated formulas. The formulas used to determine “target” NQSO and RPS grant sizes adjust for changes in the underlying value of one share of Westamerica Bancorporation stock. For achievement of corporate performance in 2022,2023, the following stock grants were awarded in January 2023:2024:

The NQSO grants have an exercise price equal to the fair market value of Westamerica Bancorporation common stock on the grant date, vest over a three-year period beginning one year from the date of grant and expire on the tenth anniversary of the grant date.

RPS awards vest three years following the grant date, only if certain corporate performance objectives are achieved over the three-year period. In January 2023,2024, the Compensation Committee evaluated whether the three-year corporate performance objectives were met for RPS awards granted in January 2020.2021. The performance objectives for the RPS granted in January 20202021 included:

The RPS would vest if any one of the following performance results were achieved:

The goals and achieved results were:

With threefour of the goals achieving the “outstanding” performance, the Compensation Committee determined the RPS shares awarded in 20202021 vested upon achievement of the three-year goals.

Nonqualified Deferred Compensation Programs. The Company maintains nonqualified deferred compensation programs to provide senior and mid-level executives the ability to defer compensation in excess of the annual limits imposed on the Company’s 401(k) plan. The Company believes these tax deferral programs enhance loyalty and motivate retention of executives. These programs allow executives to defer cash pay and RPS shares upon vesting. The programs also allow Directors to defer Director fees.

Employment Contracts. None of the executives named in the accompanying tables have employment contracts with the Company.

Compensation in the Event of a Change in Control. The banking industry has significant merger and acquisition activity. To promote retention of senior executives, unvested NQSO and RPS grants contain a “change in control” provision, which trigger full vesting upon a change in control. The Compensation Committee determined these provisions were appropriate in order to retain executives to continue managing the Company after any “change in control” was announced through its ultimate consummation. Since none of the named executive officers have entered employment contracts with the Company, they serve in an “at-will” capacity and could terminate their employment at any time. The Compensation Committee felt it would be in the best interests of shareholders to have a retention mechanism in place to provide continuity of management during a “change in control” process. Further, the Committee expects the named executive officers would be terminated by an acquiring institution rather than retained in a similar functional capacity.

The Company also maintains a Severance Payment Plan covering all employees to promote employee retention. The Severance Payment Plan provides salary continuation benefits for employees in the event of a “change in control.” The amount of salary continuation benefits is based on years of service and corporate title, but in no event exceeds the equivalent of one times annual salary. Messrs. Payne, Thorson, Donohoe, Rizzardi and RizzardiBaker are eligible for one year’s salary under the plan. Mr. Leavitt was eligible for the equivalent of 30-week’s salary under the plan as of December 31, 2022.

Internal Revenue Code. Internal Revenue Code (“IRC”) Section 162(m) places a limit on the amount of compensation that may be deducted by the Company in any year with respect to certain of the Company’s highest-paid executives. Prior to enactment of the Tax Cuts and Jobs Act of 2017 (the “Act”), certain “performance-based compensation” was not counted toward this limit. The Act eliminated the “performance-based compensation” exemption as of November 2, 2017. The Company intends generally to qualify compensation paid to executive officers for deductibility under the IRC but reserves the right to pay compensation that is not deductible.

Employee Benefits and Compensation Committee Report

We, the Compensation Committee of the Board of Directors of the Company, have reviewed and discussed the Compensation Discussion and Analysis with Management. Based on that review and discussion, we have recommended to the Board of Directors inclusion of the Compensation Discussion and Analysis in this Proxy Statement and the Company’s Annual Report on Form 10-K for the year ended December 31, 2022.2023.

Submitted by the Employee Benefits and Compensation Committee

Ronald A. Nelson,Melanie Martella Chiesa, Chair

Catherine Cope MacMillan

Melanie Martella ChiesaAlisa Belew

Inez Wondeh

Compensation Committee Interlocks and Insider Participation

No member of the Compensation Committee is a current or former officer or employee of the Company or any of its subsidiaries, or entered into (or agreed to enter into) any transaction or series of transactions with the Company or any of its subsidiaries with a value in excess of $120,000. None of the executive officers of the Company has served on the Board of Directors or on the Compensation Committee of any other entity, where one of that entity’s executive officers served either on the Board of Directors or on the Compensation Committee of the Company.

Summary Compensation

The following table sets forth summary compensation information for the chief executive officer, chief financial officer and each of the other three most highly compensated executive officers for the fiscal years ending December 31, 2023, 2022, 2021, and 2020.2021. These persons are referred to as named executive officers elsewhere in this Proxy Statement.