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                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 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 23, 2003



                          COLUMBIA BANKING SYSTEM, INC.
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             (Exact name of registrant as specified in its charter)



                                   WASHINGTON
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                 (State or other jurisdiction of incorporation)



        0-20288                                           91-1422237
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(Commission File Number)                         IRS Employer Identification No.



                                  1301 A Street
                                Tacoma, WA 98402
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               (Address of principal executive offices) (zip code)




       Registrant's telephone number, including area code: (253) 305-1900


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ITEM 12.  RESULTS OF OPERATIONS AND FINANCIAL RESULTS

          On April 23, 2003, we issued a press release announcing our first
quarter 2003 financial results. A copy of the press release is attached as
Exhibit 99.1 and is incorporated herein in its entirety by reference.



          EXHIBITS

            99.1     Press Release dated April 23, 2003 announcing First
                     Quarter 2003 Financial Results.

                                   SIGNATURES

          Pursuant to the requirements of 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.



          Dated:  April 23, 2003                  COLUMBIA BANKING SYSTEM, INC.


                                                  By: /s/  Melanie J. Dressel
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                                                      Melanie J. Dressel
                                                      Chief Executive Officer