<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-30-1999             JUN-30-1999
<PERIOD-START>                             JUL-01-1998             OCT-01-1998
<PERIOD-END>                               DEC-31-1998             DEC-31-1998
<CASH>                                       1,108,956               1,108,956
<INT-BEARING-DEPOSITS>                         264,914                 264,914
<FED-FUNDS-SOLD>                             4,146,260               4,146,260
<TRADING-ASSETS>                                     0                       0
<INVESTMENTS-HELD-FOR-SALE>                  2,857,365               2,857,365
<INVESTMENTS-CARRYING>                       2,857,365               2,857,365
<INVESTMENTS-MARKET>                         2,857,365               2,857,365
<LOANS>                                     78,697,742              78,697,742
<ALLOWANCE>                                    618,164                 618,164
<TOTAL-ASSETS>                              89,926,729              89,926,729
<DEPOSITS>                                  69,098,156              69,098,156
<SHORT-TERM>                                 1,000,000               1,000,000
<LIABILITIES-OTHER>                          1,712,522               1,712,522
<LONG-TERM>                                  8,900,000               8,900,000
<PREFERRED-MANDATORY>                                0                       0
<PREFERRED>                                          0                       0
<COMMON>                                         3,542                   3,542
<OTHER-SE>                                   9,212,509               9,212,509
<TOTAL-LIABILITIES-AND-EQUITY>              89,926,729              89,926,729
<INTEREST-LOAN>                              3,313,543               1,695,256
<INTEREST-INVEST>                              158,758                  71,937
<INTEREST-OTHER>                               126,639                  42,337
<INTEREST-TOTAL>                             3,598,940               1,809,530
<INTEREST-DEPOSIT>                           1,384,550                 684,496
<INTEREST-EXPENSE>                           1,683,726                 835,545
<INTEREST-INCOME-NET>                        1,915,214                 973,985
<LOAN-LOSSES>                                  110,000                  50,000
<SECURITIES-GAINS>                                   0                       0
<EXPENSE-OTHER>                              1,360,981                 672,115
<INCOME-PRETAX>                                558,894                 308,272
<INCOME-PRE-EXTRAORDINARY>                     558,894                 308,272
<EXTRAORDINARY>                                      0                       0
<CHANGES>                                            0                       0
<NET-INCOME>                                   350,724                 192,861
<EPS-PRIMARY>                                     1.06                    0.58
<EPS-DILUTED>                                     1.04                    0.94
<YIELD-ACTUAL>                                    8.21                    8.04
<LOANS-NON>                                    688,000                 688,000
<LOANS-PAST>                                         0                       0
<LOANS-TROUBLED>                                     0                       0
<LOANS-PROBLEM>                                      0                       0
<ALLOWANCE-OPEN>                               553,513                 583,124
<CHARGE-OFFS>                                   47,383                  15,882
<RECOVERIES>                                     2,034                     922
<ALLOWANCE-CLOSE>                              618,164                 618,164
<ALLOWANCE-DOMESTIC>                                 0                       0
<ALLOWANCE-FOREIGN>                                  0                       0
<ALLOWANCE-UNALLOCATED>                              0                       0
        

</TABLE>