Exhibit 99.1 CERTIFICATION PURSUANT TO 18 U.S.C. SECTION 1350 AS ADOPTED PURSUANT TO SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002 In connection with the Quarterly Report of Washington Federal, Inc. (the "Company") on Form 10-Q for the period ended December 31, 2002, as filed with the Securities and Exchange Commission on the date hereof (the "Report"), the undersigned hereby certify, pursuant to 18 U.S.C. section 1350, as adopted pursuant to section 906 of the Sarbanes-Oxley Act of 2002, that to the undersigned's best knowledge and belief: (a) the Report fully complies with the requirements of section 13(a) or 15(d) of the Securities Exchange Act of 1934, as amended; and (b) the information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company. Dated this 14th day of February 2003. Washington Federal, Inc. - ------------------------ (Company) /s/ Roy M. Whitehead - -------------------- Roy M. Whitehead Vice Chairman, President and Chief Executive Officer /s/ Brent J. Beardall - --------------------- Brent J. Beardall Vice President Finance and Principal Financial Officer