Westamerica Bancorporation Appoints Melanie Martella Chiesa to Its Board of Directors

Westamerica Bancorporation is a bank holding company. The Company provides a full range of banking services to individual and commercial customers in Northern and Central California through its subsidiary bank, Westamerica Bank (the Bank). The Bank is a California-chartered commercial bank whose deposits are insured by the Federal Deposit Insurance Corporation (the FDIC) up to applicable limits. The principal communities served are located in Northern and Central California, from Mendocino, Lake and Nevada Counties in the north to Kern County in the south. In addition, the Bank owns Community Banker Services Corporation, a company engaged in providing the Company and its subsidiaries with data processing services and other support functions. The Bank is engaged in the banking business through 77 branch offices in 20 counties in Northern and Central California. It owns 28 banking office locations and one centralized administrative service center facility and leases 55 facilities.