EXHIBIT 99.2

Certification of Principal Financial Officer pursuant to 18 U.S.C. Section 1350

I hereby certify pursuant to 18 U.S.C. ss. 1350, as adopted pursuant to ss. 906
of the Sarbanes-Oxley Act of 2002, to the best of my knowledge and belief, that
the accompanying Form 10-Q of Southwest Bancorp, Inc. ("Southwest") for the
quarterly period ended March 31, 2003, fully complies with the requirements of
section 13(a) or 15(d) of the Securities Exchange Act of 1934 (15 U.S.C. 78m or
78o(d)); and that the information contained in this Form 10-Q fairly presents,
in all material respects, the financial condition and results of operations of
Southwest.

By: /s/Kerby Crowell                                 May 12, 2003
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    Kerby Crowell                                    Date
    Executive Vice President, Chief Financial
    Officer and Assistant Secretary
    (Principal Financial Officer)