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                              UNITED STATES
                    SECURITIES AND EXCHANGE COMMISSION
                          Washington, DC 20549


                                 FORM 8-K


                         CURRENT REPORT PURSUANT
                       TO SECTION 13 OR 15(D) OF THE
                      SECURITIES EXCHANGE ACT OF 1934

              Date of Report (Date of earliest event reported):
                             April 27, 2006
                             --------------

                       WESTAMERICA BANCORPORATION
                       --------------------------
          (Exact Name of Registrant as Specified in Its Charter)

                                CALIFORNIA
                                ----------
              (State or Other Jurisdiction of Incorporation)


                001-9383                       94-2156203
                --------                       ----------
        (Commission File Number)    (IRS Employer Identification No.)


         1108 Fifth Avenue, San Rafael, California          94901
         ----------------------------------------------------------
          (Address of Principal Executive Offices)        (Zip Code)


                               (707) 863-6000
                               --------------
            (Registrant's Telephone Number, Including Area Code)


   Check the appropriate box below if the Form 8-K filing is intended to
simultaneously satisfy the filing obligation of the registrant under any
of the following provisions:

      []  Written communications pursuant to Rule 425 under the Securities
          Act (17 CFR 230.425)

      []  Soliciting material pursuant to Rule 14a-12 under the Exchange
          Act (17 CFR 240.14a-12)

      []  Pre-commencement communications pursuant to Rule 14d-2(b) under
          the Exchange Act (17 CFR 240.14d-2(b))

      []  Pre-commencement communications pursuant to Rule 13e-4(c) under
          the Exchange Act (17 CFR 240.13e-4c))

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Exhibits
---------

99.1 Press release dated April 27, 2006


Item 8.01:  Other Events
------------------------

On April 27, 2006 Westamerica Bancorporation declared a quarterly cash
dividend.  A copy of the press release is attached as Exhibit 99.1 to this Form
8-K and is incorporated herein by reference.




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                                 Signatures

Pursuant to the Securities Exchange Act of 1934, the registrant has
duly caused this report to be signed on its behalf by the undersigned
hereunto duly authorized.

Westamerica Bancorporation

/s/    JOHN "ROBERT" THORSON
-------------------------------------------------
John "Robert" Thorson
Senior Vice President and Chief Financial Officer
April 27, 2006






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INDEX TO EXHIBITS
-----------------


                                                         Sequentially
Exhibit No.             Description                      Number Page
-----------             -------------------------        -------------
  (99.1)                 Press release dated                  5-6
                         April 27, 2006



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Exhibit 99.1:
-------------


FOR IMMEDIATE RELEASE

April 27, 2006


WESTAMERICA BANCORPORATION DECLARES
QUARTERLY CASH DIVIDEND


San Rafael, CA:	The Board of Directors of Westamerica Bancorporation (NASDAQ:
WABC) today declared a quarterly cash dividend of $0.32 per share on common
stock outstanding to shareholders of record at the close of business on May 8,
2006. The dividend is payable May 19, 2006.

As previously announced, Westamerica Bancorporation reported quarterly earnings
for the first quarter of 2006 of $26.1 million or $0.81 diluted earnings per
share.

Westamerica Bancorporation through its wholly owned subsidiary, Westamerica
Bank, operates 87 branches and two trust offices throughout 21 Northern and
Central California counties.

Westamerica Bancorporation Web Address: www.westamerica.com

For additional information contact:
      Westamerica Bancorporation
      Robert A. Thorson  -  SVP & Chief Financial Officer
	707-863-6840


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FORWARD-LOOKING INFORMATION:

   The following appears in accordance with the Private Securities Litigation
Reform Act of 1995:
   This press release may contain forward-looking statements about the Company,
including descriptions of plans or objectives of its management for future
operations, products or services, and forecasts of its revenues, earnings or
other measures of economic performance.  Forward-looking statements can be
identified by the fact that they do not relate strictly to historical or current
facts.  They often include the words "believe," "expect," "anticipate,"
"intend," "plan," "estimate," or words of similar meaning, or future or
conditional verbs such as "will," "would," "should," "could," or "may."
   Forward-looking statements, by their nature, are subject to risks and
uncertainties. A number of factors - many of which are beyond the Company's
control - could cause actual conditions, events or results to differ
significantly from those described in the forward-looking statements.  The
Company's most recent annual and quarterly reports filed with the Securities and
Exchange Commission, including the Company's Form 10-K for the year ended
December 31, 2005, describe some of these factors, including certain credit,
market, operational, liquidity and interest rate risks associated with the
Company's business and operations.  Other factors described in these reports
include changes in business and economic conditions, competition, fiscal and
monetary policies, disintermediation, legislation including the Sarbanes-Oxley
Act of 2002 and the Gramm-Leach-Bliley Act of 1999, and mergers and
acquisitions.
   Forward-looking statements speak only as of the date they are made.  The
Company does not undertake to update forward-looking statements to reflect
circumstances or events that occur after the date forward looking statements are
made.
                                      #####