WESTAMERICA BANCORPORATION

Management of Westamerica Bancorporation and subsidiaries (the “Company”) is responsible for establishing and maintaining adequate internal control over financial reporting, and for performing an assessment of the effectiveness of internal control over financial reporting as of December 31, 2024. Internal control over financial reporting is a process designed to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles. The Company’s system of internal control over financial reporting includes those policies and procedures that (i) pertain to the maintenance of records that, in reasonable detail, accurately and fairly reflect the transactions and dispositions of the assets of the Company; (ii) provide reasonable assurance that transactions are recorded as necessary to permit preparation of financial statements in accordance with generally accepted accounting principles, and that receipts and expenditures of the Company are being made only in accordance with authorizations of Management and Directors of the Company; and (iii) provide reasonable assurance regarding prevention or timely detection of unauthorized acquisition, use or disposition of the Company’s assets that could have a material effect on the financial statements.

Management performed an assessment of the effectiveness of the Company’s internal control over financial reporting as of December 31, 2024 based upon criteria in Internal Control — Integrated Framework (2013) issued by the Committee of Sponsoring Organizations of the Treadway Commission (“COSO”). Based on this assessment, Management determined that the Company’s internal control over financial reporting was effective as of December 31, 2024 based on the criteria in Internal Control - Integrated Framework (2013) issued by COSO.

The Company’s independent registered public accounting firm has issued an attestation report on the Company’s internal control over financial reporting. Their opinion and attestation on internal control over financial reporting appear on page 88.

Dated: February 28, 2025

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WESTAMERICA BANCORPORATION