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Exhibit 32.2



CERTIFICATION PURSUANT TO
18 U.S.C. SECTION 1350
AS ADOPTED PURSUANT TO
SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002


In connection with the Quarterly Report of Westamerica Bancorporation
(the Company) on Form 10-Q for the period ending June 30, 2004 as filed
with the Securities and Exchange Commission on the date hereof (the
"Report"), I, Jennifer J. Finger, Chief Financial Officer of the Company,
certify, pursuant to 18 U.S.C. Section 1350, as adopted pursuant to
Section 906 of the Sarbanes-Oxley Act of 2002, that:
(1) The Report fully complies with the requirements of section
    13(a)-14(b) or 15d-14(b) of the Securities Exchange Act of
    1934; and

(2) The information contained in the Report fairly presents, in all
      material respects, the financial condition and results of
      operations of the Company.







/s/  Jennifer J. Finger                              November 9, 2004
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Jennifer J. Finger                                   Date
Senior Vice President and Chief Financial Officer