<TABLE> <S> <C>

<PAGE>
<ARTICLE> 9
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM PATAPSCO
BANCORP, INC. AND SUBSIDIARY AND IS QUALIFIED IN ITS ENTIRETY BY REFERENCE TO
SUCH FINANCIAL STATEMENTS.
</LEGEND>
       
<S>                             <C>                     <C>
<PERIOD-TYPE>                   6-MOS                   3-MOS
<FISCAL-YEAR-END>                          JUN-30-1998             JUN-30-1998
<PERIOD-START>                             JUL-01-1997             JUL-01-1997
<PERIOD-END>                               DEC-31-1997             DEC-31-1997
<CASH>                                       1,074,587               1,074,587
<INT-BEARING-DEPOSITS>                       5,390,814               5,390,814
<FED-FUNDS-SOLD>                             1,371,385               1,371,385
<TRADING-ASSETS>                                     0                       0
<INVESTMENTS-HELD-FOR-SALE>                  5,017,190               5,017,190
<INVESTMENTS-CARRYING>                       5,017,190               5,017,190
<INVESTMENTS-MARKET>                         5,017,190               5,017,190
<LOANS>                                     74,017,499              74,017,499
<ALLOWANCE>                                    495,309                 495,309
<TOTAL-ASSETS>                              89,255,872              89,255,872
<DEPOSITS>                                  69,114,173              69,114,173
<SHORT-TERM>                                 1,200,000               1,200,000
<LIABILITIES-OTHER>                            853,108                 853,108
<LONG-TERM>                                  9,400,000               9,400,000
<PREFERRED-MANDATORY>                                0                       0
<PREFERRED>                                          0                       0
<COMMON>                                         3,626                   3,626
<OTHER-SE>                                   8,684,965               8,684,965
<TOTAL-LIABILITIES-AND-EQUITY>              89,255,872              89,255,872
<INTEREST-LOAN>                              2,972,477               1,528,594
<INTEREST-INVEST>                              344,407                 131,423
<INTEREST-OTHER>                               144,232                 111,634
<INTEREST-TOTAL>                             3,461,116               1,771,651
<INTEREST-DEPOSIT>                           1,425,051                 727,119
<INTEREST-EXPENSE>                           1,718,348                 890,242
<INTEREST-INCOME-NET>                        1,742,768                 881,409
<LOAN-LOSSES>                                  120,000                  60,000
<SECURITIES-GAINS>                               5,015                  14,237
<EXPENSE-OTHER>                              1,259,226                 621,113
<INCOME-PRETAX>                                505,207                 286,914
<INCOME-PRE-EXTRAORDINARY>                     505,207                 286,914
<EXTRAORDINARY>                                      0                       0
<CHANGES>                                            0                       0
<NET-INCOME>                                   319,264                 181,909
<EPS-PRIMARY>                                     0.94                    0.54
<EPS-DILUTED>                                     0.94                    0.54
<YIELD-ACTUAL>                                    8.13                    8.04
<LOANS-NON>                                    173,000                 173,000
<LOANS-PAST>                                   173,000                 173,000
<LOANS-TROUBLED>                                     0                       0
<LOANS-PROBLEM>                                      0                       0
<ALLOWANCE-OPEN>                               397,012                 457,405
<CHARGE-OFFS>                                   25,801                  40,605
<RECOVERIES>                                     4,098                   2,701
<ALLOWANCE-CLOSE>                              495,309                 495,309
<ALLOWANCE-DOMESTIC>                                 0                       0
<ALLOWANCE-FOREIGN>                                  0                       0
<ALLOWANCE-UNALLOCATED>                              0                       0
        

</TABLE>