<TABLE> <S> <C>
<PAGE>
<ARTICLE> 9
<LEGEND>
THIS SCHEDULE CONTAINS FINANCIAL INFORMATION EXTRACTED FROM THE CONSOLIDATED
FINANCIAL STATEMENTS OF CONNECTICUT BANCSHARES, INC. FOR THE SIX MONTHS ENDED
JUNE 30, 2000 AND IS QUALIFIED IN ITS ENTIRETY BY REFERENCE TO SUCH FINANCIAL
STATEMENTS.
</LEGEND>
<MULTIPLIER> 1,000
<S> <C> <C>
<PERIOD-TYPE> 6-MOS 9-MOS
<FISCAL-YEAR-END> DEC-31-2000 DEC-31-2000
<PERIOD-START> JAN-01-2000 JAN-01-2000
<PERIOD-END> JUN-30-2000 SEP-30-2000
<CASH> 31,175 40,329
<INT-BEARING-DEPOSITS> 9 14
<FED-FUNDS-SOLD> 25,007 11,318
<TRADING-ASSETS> 0 0
<INVESTMENTS-HELD-FOR-SALE> 0 0
<INVESTMENTS-CARRYING> 295,504 272,970
<INVESTMENTS-MARKET> 311,939 293,430
<LOANS> 995,239 1,012,407
<ALLOWANCE> 11,158 11,561
<TOTAL-ASSETS> 1,388,227 1,380,791
<DEPOSITS> 918,751 904,188
<SHORT-TERM> 114,778 109,088
<LIABILITIES-OTHER> 9,571 10,532
<LONG-TERM> 114,000 124,000
0 0
0 0
<COMMON> 112 112
<OTHER-SE> 220,883 228,370
<TOTAL-LIABILITIES-AND-EQUITY> 1,388,227 1,380,791
<INTEREST-LOAN> 36,734 58,311
<INTEREST-INVEST> 8,733 13,668
<INTEREST-OTHER> 0 0
<INTEREST-TOTAL> 45,467 69,979
<INTEREST-DEPOSIT> 18,212 24,862
<INTEREST-EXPENSE> 21,180 32,461
<INTEREST-INCOME-NET> 24,287 37,518
<LOAN-LOSSES> 450 825
<SECURITIES-GAINS> (1,784) (990)
<EXPENSE-OTHER> 28,466 38,467
<INCOME-PRETAX> (1,687) 4,584
<INCOME-PRE-EXTRAORDINARY> (1,687) 4,584
<EXTRAORDINARY> 0 0
<CHANGES> 0 0
<NET-INCOME> (1,134) 3,064
<EPS-BASIC> 0.31 0.40
<EPS-DILUTED> 0.31 0.40
<YIELD-ACTUAL> 7.15 7.25
<LOANS-NON> 8,008 7,544
<LOANS-PAST> 646 1,661
<LOANS-TROUBLED> 0 0
<LOANS-PROBLEM> 0 0
<ALLOWANCE-OPEN> 10,617 10,617
<CHARGE-OFFS> 110 126
<RECOVERIES> 201 245
<ALLOWANCE-CLOSE> 11,158 11,561
<ALLOWANCE-DOMESTIC> 11,158 11,561
<ALLOWANCE-FOREIGN> 0 0
<ALLOWANCE-UNALLOCATED> 11,158 11,561
</TABLE>