Ownership Submission
FORM 4
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940
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(Print or Type Responses)
1. Name and Address of Reporting Person *
HANSEN DENNIS R
  2. Issuer Name and Ticker or Trading Symbol
WESTAMERICA BANCORPORATION [WABC]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
Sr. Vice President/Controller
(Last)
(First)
(Middle)
3. Date of Earliest Transaction (Month/Day/Year)
10/27/2004
(Street)

 
4. If Amendment, Date Original Filed(Month/Day/Year)
6. Individual or Joint/Group Filing(Check Applicable Line)
_X_ Form filed by One Reporting Person
___ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1.Title of Security
(Instr. 3)
2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code
(Instr. 8)
4. Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4 and 5)
5. Amount of Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 3 and 4)
6. Ownership Form: Direct (D) or Indirect (I)
(Instr. 4)
7. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V Amount (A) or (D) Price
Common Stock 10/27/2004   M   100 A $ 15.4583 803 D  
Common Stock 10/27/2004   S   100 D $ 56.14 703 D  
Common Stock 10/27/2004   M   9 A $ 15.4583 712 D  
Common Stock 10/27/2004   S   9 D $ 56.2 703 D  
Common Stock 10/27/2004   M   300 A $ 15.4583 1,003 D  
Common Stock 10/27/2004   S   300 D $ 56.25 703 D  
Common Stock 10/27/2004   M   400 A $ 15.4583 1,103 D  
Common Stock 10/27/2004   S   400 D $ 56.27 703 D  
Common Stock 10/27/2004   M   100 A $ 15.4583 803 D  
Common Stock 10/27/2004   S   100 D $ 56.3 703 D  
Common Stock 10/27/2004   M   200 A $ 15.4583 903 D  
Common Stock 10/27/2004   S   200 D $ 56.33 703 D  
Common Stock 10/27/2004   M   352 A $ 15.4583 1,055 D  
Common Stock 10/27/2004   S   352 D $ 56.38 703 D  
Common Stock 10/27/2004   M   300 A $ 15.4583 1,003 D  
Common Stock 10/27/2004   S   300 D $ 56.35 703 D  
Common Stock 10/27/2004   M   200 A $ 15.4583 903 D  
Common Stock 10/27/2004   S   200 D $ 56.32 703 D  
Common Stock 10/27/2004   M   300 A $ 15.4583 1,003 D  
Common Stock 10/27/2004   S   300 D $ 56.29 703 D  

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
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Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 3)
2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (Month/Day/Year) 3A. Deemed Execution Date, if any (Month/Day/Year) 4. Transaction Code
(Instr. 8)
5. Number of Derivative Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4, and 5)
6. Date Exercisable and Expiration Date
(Month/Day/Year)
7. Title and Amount of Underlying Securities
(Instr. 3 and 4)
8. Price of Derivative Security
(Instr. 5)
9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 4)
10. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 4)
11. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares
Non-Qualified Stock Option (right to buy) $ 15.4583 10/27/2004   M     100 01/24/1997(1) 01/24/2006 Common Stock 100 $ 0 5,850 D  
Non-Qualified Stock Option (right to buy) $ 15.4583 10/27/2004   M     9 01/24/1997(1) 01/24/2006 Common Stock 9 $ 0 5,841 D  
Non-Qualified Stock Option (right to buy) $ 15.4583 10/27/2004   M     300 01/24/1997(1) 01/24/2006 Common Stock 300 $ 0 5,541 D  
Non-Qualified Stock Option (right to buy) $ 15.4583 10/27/2004   M     400 01/24/1997(1) 01/24/2006 Common Stock 400 $ 0 5,141 D  
Non-Qualified Stock Option (right to buy) $ 15.4583 10/27/2004   M     100 01/24/1997(1) 01/24/2006 Common Stock 100 $ 0 5,041 D  
Non-Qualified Stock Option (right to buy) $ 15.4583 10/27/2004   M     200 01/24/1997(1) 01/24/2006 Common Stock 200 $ 0 4,841 D  
Non-Qualified Stock Option (right to buy) $ 15.4583 10/27/2004   M     352 01/24/1997(1) 01/24/2006 Common Stock 352 $ 0 4,489 D  
Non-Qualified Stock Option (right to buy) $ 15.4583 10/27/2004   M     300 01/24/1997(1) 01/24/2006 Common Stock 300 $ 0 4,189 D  
Non-Qualified Stock Option (right to buy) $ 15.4583 10/27/2004   M     200 01/24/1997(1) 01/24/2006 Common Stock 200 $ 0 3,989 D  
Non-Qualified Stock Option (right to buy) $ 15.4583 10/27/2004   M     300 01/24/1997(1) 01/24/2006 Common Stock 300 $ 0 3,689 D  
Non-Qualified Stock Option (right to buy) $ 15.4583 10/27/2004   M     600 01/24/1997(1) 01/24/2006 Common Stock 600 $ 0 3,089 D  
Non-Qualified Stock Option (right to buy) $ 15.4583 10/27/2004   M     300 01/24/1997(1) 01/24/2006 Common Stock 300 $ 0 2,789 D  
Non-Qualified Stock Option (right to buy) $ 15.4583 10/27/2004   M     900 01/24/1997(1) 01/24/2006 Common Stock 900 $ 0 1,889 D  
Non-Qualified Stock Option (right to buy) $ 15.4583 10/27/2004   M     300 01/24/1997(1) 01/24/2006 Common Stock 300 $ 0 1,589 D  
Non-Qualified Stock Option (right to buy) $ 15.4583 10/27/2004   M     500 01/24/1997(1) 01/24/2006 Common Stock 500 $ 0 1,089 D  
Non-Qualified Stock Opton (right to buy) $ 15.4583 10/27/2004   M     1,089 01/24/1997(1) 01/24/2006 Common Stock 1,089 $ 0 0 D  

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
HANSEN DENNIS R

 
      Sr. Vice President/Controller  

Signatures

 By: Dennis R. Hansen   10/28/2004
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 4(b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1) These options vest ratably over three years beginning one year from date of grant.
 
Remarks:
This is Form 4 #1 of 2 Form 4s for this reporting person for the date of 10/27/2004.

Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.

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