<TABLE> <S> <C>
<PAGE>
<ARTICLE> 9
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM NATIONAL
MERCANTILE BANCORP'S JUNE 30, 2000 CONSOLIDATED FINANCIAL STATEMENTS AND RELATED
SCHEDULES.
</LEGEND>
<MULTIPLIER> 1,000
<S> <C>
<PERIOD-TYPE> 6-MOS
<FISCAL-YEAR-END> DEC-31-2000
<PERIOD-START> JAN-01-2000
<PERIOD-END> JUN-30-2000
<CASH> 12,472
<INT-BEARING-DEPOSITS> 0
<FED-FUNDS-SOLD> 2,015
<TRADING-ASSETS> 0
<INVESTMENTS-HELD-FOR-SALE> 69,546
<INVESTMENTS-CARRYING> 0
<INVESTMENTS-MARKET> 0
<LOANS> 93,956
<ALLOWANCE> 2,546
<TOTAL-ASSETS> 177,780
<DEPOSITS> 121,312
<SHORT-TERM> 31,300
<LIABILITIES-OTHER> 1,541
<LONG-TERM> 10,500
0
6,415
<COMMON> 25,550
<OTHER-SE> (18,838)
<TOTAL-LIABILITIES-AND-EQUITY> 177,780
<INTEREST-LOAN> 3,849
<INTEREST-INVEST> 2,433
<INTEREST-OTHER> 174
<INTEREST-TOTAL> 6,456
<INTEREST-DEPOSIT> 1,244
<INTEREST-EXPENSE> 2,110
<INTEREST-INCOME-NET> 4,346
<LOAN-LOSSES> (576)
<SECURITIES-GAINS> 18
<EXPENSE-OTHER> 3,845
<INCOME-PRETAX> 1,563
<INCOME-PRE-EXTRAORDINARY> 0
<EXTRAORDINARY> 0
<CHANGES> 0
<NET-INCOME> 1,537
<EPS-BASIC> 1.80
<EPS-DILUTED> 0.61
<YIELD-ACTUAL> 5.49
<LOANS-NON> 484
<LOANS-PAST> 262
<LOANS-TROUBLED> 0
<LOANS-PROBLEM> 7
<ALLOWANCE-OPEN> 1,896
<CHARGE-OFFS> 107
<RECOVERIES> 1,333
<ALLOWANCE-CLOSE> 2,546
<ALLOWANCE-DOMESTIC> 1,355
<ALLOWANCE-FOREIGN> 0
<ALLOWANCE-UNALLOCATED> 1,191
</TABLE>