<ARTICLE> 9
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM SOUTHWEST
BANCORP'S QUARTERLY REPORT ON FORM 10-Q FOR THE QUARTER ENDED SEPTEMBER 30,
1999, AND IS QUALIFIED IN ITS ENTIRETY BY REFERENCE TO SUCH FINANCIAL
STATEMENTS.
</LEGEND>
<MULTIPLIER> 1,000

                             
<PERIOD-TYPE>                   9-MOS
<FISCAL-YEAR-END>                          DEC-31-1999
<PERIOD-START>                             JAN-01-1999
<PERIOD-END>                               SEP-30-1999
<CASH>                                          21,542
<INT-BEARING-DEPOSITS>                           1,008
<FED-FUNDS-SOLD>                                   100
<TRADING-ASSETS>                                     0
<INVESTMENTS-HELD-FOR-SALE>                    133,333
<INVESTMENTS-CARRYING>                          79,419
<INVESTMENTS-MARKET>                            79,320
<LOANS>                                        803,161
<ALLOWANCE>                                     10,886
<TOTAL-ASSETS>                               1,069,912
<DEPOSITS>                                     826,107
<SHORT-TERM>                                   144,016
<LIABILITIES-OTHER>                              8,176
<LONG-TERM>                                     25,013
<PREFERRED-MANDATORY>                                0
<PREFERRED>                                          0
<COMMON>                                         4,081
<OTHER-SE>                                      62,519
<TOTAL-LIABILITIES-AND-EQUITY>               1,069,912
<INTEREST-LOAN>                                 51,457
<INTEREST-INVEST>                                8,013
<INTEREST-OTHER>                                    28
<INTEREST-TOTAL>                                59,498
<INTEREST-DEPOSIT>                              25,303
<INTEREST-EXPENSE>                              31,057
<INTEREST-INCOME-NET>                           28,441
<LOAN-LOSSES>                                    1,700
<SECURITIES-GAINS>                                  86
<EXPENSE-OTHER>                                 21,889
<INCOME-PRETAX>                                 11,208
<INCOME-PRE-EXTRAORDINARY>                      11,208
<EXTRAORDINARY>                                      0
<CHANGES>                                            0
<NET-INCOME>                                     7,205
<EPS-BASIC>                                       1.81
<EPS-DILUTED>                                     1.77
<YIELD-ACTUAL>                                    8.06
<LOANS-NON>                                      5,741
<LOANS-PAST>                                        14
<LOANS-TROUBLED>                                     0
<LOANS-PROBLEM>                                 26,400
<ALLOWANCE-OPEN>                                10,401
<CHARGE-OFFS>                                    1,702
<RECOVERIES>                                       487
<ALLOWANCE-CLOSE>                               10,886
<ALLOWANCE-DOMESTIC>                            10,886
<ALLOWANCE-FOREIGN>                                  0
<ALLOWANCE-UNALLOCATED>                          2,620