Columbia Banking System To Present At The D.A. Davidson Financial Services Conference In Seattle, Washington On May 11, 2011

TACOMA, Wash., May 3, 2011 /PRNewswire/ -- Columbia Banking System, Inc. (NASDAQ: COLB) announced today that Melanie J. Dressel, President and Chief Executive Officer, is scheduled to present at the D.A. Davidson & Co. 13th Annual Financial Services Conference in Seattle, Washington.  The Columbia Banking System presentation is scheduled for Wednesday, May 11 at 1:30 p.m. Pacific time ( 4:30 p.m. Eastern).  Ms. Dressel will also participate in an "Emerging M & A Market CEO panel discussion, which is scheduled for 10:45 a.m. PDT on May 11.

The webcast of the presentation can be accessed through a presentation link at http://www.wsw.com/webcast/dadco21/colb/ or by visiting www.columbiabank.com and clicking on the D.A. Davidson Conference link. The webcast will be archived for 90 days following the live presentation.

About Columbia

Headquartered in Tacoma, Washington, Columbia Banking System, Inc. is the holding company of Columbia Bank, a Washington state-chartered full-service commercial bank which was awarded third place in the large employer category by Seattle Business Magazine's 100 Best Companies to Work For 2010 and was designated one of  Puget Sound Business Journal's " Washington's Best Workplaces 2010".

Columbia Banking System has 85 banking offices, including 60 branches in Washington State and 25 branches in Oregon. Columbia Bank does business under the Bank of Astoria name at the Bank of Astoria's former branches located in Astoria, Warrenton, Seaside, Cannon Beach, Manzanita and Tillamook. More information about Columbia can be found on its website at www.columbiabank.com.

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