ANNUAL REPORT ON FORM 10-K

Company

COLUMBIA BANKING SYSTEM, INC.

Filed

March 7, 2006

Period of Report

December 31, 2005

Accession Number

0001193125-06-047205

A 10-K is a company's comprehensive annual report, required by the SEC. It includes audited financial statements, a description of the business, risk factors, and management's discussion of results. Learn more about 10-K filings →