<TABLE> <S> <C>

<PAGE>
<ARTICLE> 9
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM NATIONAL
MERCANTILE BANCORP CONSOLIDATED BALANCE SHEETS, STATEMENTS OF OPERATIONS,
SHAREHOLDERS' EQUITY AND VARIOUS SCHEDULES FOR THE YEAR ENDED DECEMBER 31, 1998
AND IS QUALIFIED IN ITS ENTIRETY BY REFERENCE TO SUCH FINANCIAL STATEMENTS.
</LEGEND>
<MULTIPLIER> 1,000
       
<S>                             <C>
<PERIOD-TYPE>                   YEAR
<FISCAL-YEAR-END>                          DEC-31-1998
<PERIOD-START>                             JAN-01-1998
<PERIOD-END>                               DEC-31-1998
<CASH>                                           5,405
<INT-BEARING-DEPOSITS>                               0
<FED-FUNDS-SOLD>                                 6,800
<TRADING-ASSETS>                                     0
<INVESTMENTS-HELD-FOR-SALE>                     71,849
<INVESTMENTS-CARRYING>                               0
<INVESTMENTS-MARKET>                                 0
<LOANS>                                         56,972
<ALLOWANCE>                                      2,144
<TOTAL-ASSETS>                                 141,623
<DEPOSITS>                                     106,972
<SHORT-TERM>                                     5,800
<LIABILITIES-OTHER>                              1,093
<LONG-TERM>                                     14,500
<PREFERRED-MANDATORY>                                0
<PREFERRED>                                      7,350
<COMMON>                                        24,613
<OTHER-SE>                                    (18,705)
<TOTAL-LIABILITIES-AND-EQUITY>                 141,623
<INTEREST-LOAN>                                  5,937
<INTEREST-INVEST>                                3,349
<INTEREST-OTHER>                                   795
<INTEREST-TOTAL>                                10,081
<INTEREST-DEPOSIT>                               2,833
<INTEREST-EXPENSE>                               3,485
<INTEREST-INCOME-NET>                            6,596
<LOAN-LOSSES>                                        0
<SECURITIES-GAINS>                                  39
<EXPENSE-OTHER>                                  6,798
<INCOME-PRETAX>                                    653
<INCOME-PRE-EXTRAORDINARY>                         645
<EXTRAORDINARY>                                      0
<CHANGES>                                            0
<NET-INCOME>                                       645
<EPS-PRIMARY>                                     0.95
<EPS-DILUTED>                                     0.25
<YIELD-ACTUAL>                                    5.18
<LOANS-NON>                                      1,505
<LOANS-PAST>                                         0
<LOANS-TROUBLED>                                     0
<LOANS-PROBLEM>                                     41
<ALLOWANCE-OPEN>                                 2,023
<CHARGE-OFFS>                                      407
<RECOVERIES>                                       528
<ALLOWANCE-CLOSE>                                2,144
<ALLOWANCE-DOMESTIC>                             1,359
<ALLOWANCE-FOREIGN>                                  0
<ALLOWANCE-UNALLOCATED>                            785
        

</TABLE>