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:   May 1, 1998


                       Columbia Banking System, Inc.
                       -----------------------------
            (Exact name of registrant as specified in its charter)

                                 Washington
                                 ----------
                (State or other jurisdiction of incorporation)


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


                            1102 Broadway Plaza
                             Tacoma, WA   98402
            (Address of principal executive offices) (Zip Code)

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





                                  FORM 8-K

                         COLUMBIA BANKING SYSTEM, INC.
                              Tacoma, Washington

                                 May 1, 1998


Item 5.  Other Events
- ---------------------

   On April 22, 1998, the Board of Directors of Columbia Banking System, Inc.,
Tacoma, Washington ("CBSI"), declared a three shares for two stock split
payable on May 20, 1998, to shareholders of record on May 6, 1998.  This is the
first stock split declared by CBSI since its initial public offering in
June 1992.

   A copy of CBSI's News Release containing the announcement of the stock split
is attached as an exhibit to this repport.

   Also on April 22, 1998, CBSI's Board of Directors appointed J. James
Gallagher as Vice Chairman and a member of the Board.  Mr. Gallagher will
be responsible for strategic planning, mergers and acquisitions, and legal
and regulatory compliance.  He will join Executive Vice Presidents Melanie
Dressel and H.R. Russell as the executive managers of CBSI, reporting directly
to Chairman and Chief Executive Officer, W.W. Philip.  Mr. Gallagher is
currently a principal in the law firm of Gordon, Thomas, Honeywell, Malanca,
Peterson & Daheim, PLLC, located in Tacoma, Washington.  Mr. Gallagher has
practiced law in the Pacific Northwest for 30 years and has represented large
and small financial institutions throughout the Northwest, including CBSI and
the former Puget Sound Bancorp.  Mr. Philip noted that Mr. Gallagher's
appointment clearly signifies CBSI's intent and strong desire to continue to
develop as an independent entity with a significant presence in the State of
Washington.

   A copy of CBSI's News Release containing the announcement of Mr. Gallagher's
appointment is attached as an exhibit to this report.

   CBSI's common stock trades on the Nasdaq National Market tier of The Nasdaq
Stock Market under the symbol "COLB".

                                  -2-



Item 7.  Financial Statements and Exhibits
- ------------------------------------------

        (a)  Financial statements - not applicable.

        (b)  Pro forma financial information - not applicable.

        (c)  Exhibits:

        (20) News releases issued by Columbia Banking System, Inc.
             dated April 22, 1998.



                                  -3-


                               SIGNATURES

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

                                        COLUMBIA BANKING SYSTEM, INC.
                                        (Registrant)


Date:  May 1, 1998          By:    /s/ W.W. Philip
                               -----------------------------------------   
                                       W.W. Philip, Chairman,
                                       President and Chief Executive
                                       Officer


                                    -4-

                                 Exhibit (20)





                            (Columbia Banking System
                             letterhead appears here)



                                                      FOR IMMEDIATE RELEASE
                                                      April 22, 1998


Contacts: W. W. Philip, Chairman and Chief Executive Officer, (253) 305-1993
          Kristen Kopay, Corporate Communications, (253) 305-1965


                           COLUMBIA BANKING SYSTEM 
                        ANNOUNCES 3 FOR 2 STOCK SPLIT 


TACOMA, Washington---W. W. Philip, Chairman and Chief Executive Officer of
Columbia Banking System, Inc. (Nasdaq: COLB) has declared a three shares for
two stock split payable on May 20, 1998, to shareholders of record on
May 6, 1998.  The announcement was made at today's Annual Meeting of
Shareholders.  This marks the first stock split since the Company's initial
public offering in June 1992.

   Philip noted that, "in order to conserve capital for Columbia's continued
growth and expansion, we have declared this three for two split in lieu of
a cash dividend."

   Columbia Banking System is a Tacoma, Washington-based bank holding company
which operates Columbia Bank, a state-chartered full-service commercial bank
with 23 branch offices in Pierce, King and Cowlitz counties.

                                    ###  

1102 Broadway Plaza (98402) * P.O. Box 2156 * Tacoma, Washington 98401-2156
(253) 305-1900 * Fax (253) 272-2807



Columbia Bank continue its rapid growth and geographic expansion.  We think
he is uniquely qualified to help us achieve these goals while continuing to
deliver strong customer service and sound asset quality.  He will work closely
with Melanie Dressel and Hal Russell who will continue to lead the retail and
commercial functions of the Bank.

   "Jim's appointment as a senior executive of the Company clearly signifies
our intent and strong desire to continue to develop Columbia Bank as an
independent entity that will have a significant presence in the state of
Washington."

   Active in civic affairs for the Tacoma-Pierce County community, Gallagher
is currently a member of the Executive Committee of the Economic Development
Board of Tacoma-Pierce County and recently served as a member of the Board of
the Tacoma-Pierce County Chamber of Commerce.  He also serves on the Board of
MultiCare Health System, the parent for Tacoma General, Mary Bridge Children's
and Allenmore hospitals.

   Columbia Banking System is a Tacoma, Washington-based bank holding company
which operates Columbia Bank, a state-chartered full-service commercial bank
with 23 branch offices in Pierce, King and Cowlitz counties.

                                    ###



1102 Broadway Plaza (98402) * P.O. Box 2156 * Tacoma, Washington 98401-2156
(253) 305-1900 * Fax (253) 272-2807