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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 24, 2008
                             --------------

                       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 24, 2008

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

On April 24, 2008 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 24, 2008


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

                                                         Sequentially
Exhibit No.             Description                      Number Page
-----------             -------------------------        -------------
  (99.1)                 Press release dated                  5-6
                         April 24, 2008


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

FOR IMMEDIATE RELEASE

April 24, 2008

WESTAMERICA BANCORPORATION INCREASES
QUARTERLY CASH DIVIDEND


San Rafael, CA:	The Board of Directors of Westamerica Bancorporation (NASDAQ:
WABC) today declared a quarterly cash dividend of $0.35 per common share
outstanding to shareholders of record at the close of business on May 5, 2008.
The dividend is payable May 16, 2008.

This cash dividend represents an increase from $0.34 per common share declared
in the previous quarter.  Chairman, President & CEO David Payne stated, "This
dividend increase recognizes Westamerica's healthy level of profitability, asset
quality, and capital."

On April 15, 2008, Westamerica reported $26.8 million in net income for the
quarter ended March 31, 2008, generating 27.3 percent return on shareholders'
equity.

Westamerica Bancorporation, through its wholly owned subsidiary, Westamerica
Bank, operates 86 branches 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 10-K for the year ended December
31, 2007, 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.

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