<TABLE> <S> <C>
<PAGE>
<ARTICLE> 7
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM THE
FINANCIAL STATEMENTS CONTAINED IN THE FORM 10Q FOR THE PERIOD ENDED
SEPTEMBER 30, 2000 FOR RLI CORP. AND IS QUALIFIED IN ITS ENTIRETY BY REFERENCE
TO SUCH FINANCIAL STATEMENTS.
</LEGEND>
<MULTIPLIER> 1,000
<S> <C>
<PERIOD-TYPE> 9-MOS
<FISCAL-YEAR-END> DEC-31-2000
<PERIOD-START> JAN-01-2000
<PERIOD-END> SEP-30-2000
<DEBT-HELD-FOR-SALE> 86,680
<DEBT-CARRYING-VALUE> 309,444
<DEBT-MARKET-VALUE> 309,747
<EQUITIES> 294,648
<MORTGAGE> 0
<REAL-ESTATE> 0
<TOTAL-INVEST> 744,261
<CASH> 0
<RECOVER-REINSURE> 231,141
<DEFERRED-ACQUISITION> 45,321
<TOTAL-ASSETS> 1,265,642
<POLICY-LOSSES> 533,857
<UNEARNED-PREMIUMS> 211,592
<POLICY-OTHER> 0
<POLICY-HOLDER-FUNDS> 0
<NOTES-PAYABLE> 78,539
0
0
<COMMON> 12,806
<OTHER-SE> 299,796
<TOTAL-LIABILITY-AND-EQUITY> 1,265,642
172,081
<INVESTMENT-INCOME> 21,483
<INVESTMENT-GAINS> 517
<OTHER-INCOME> 0
<BENEFITS> 94,337
<UNDERWRITING-AMORTIZATION> 55,234
<UNDERWRITING-OTHER> 13,224
<INCOME-PRETAX> 28,117
<INCOME-TAX> 7,236
<INCOME-CONTINUING> 20,881
<DISCONTINUED> 0
<EXTRAORDINARY> 0
<CHANGES> 0
<NET-INCOME> 20,881
<EPS-BASIC> 2.13
<EPS-DILUTED> 2.10
<RESERVE-OPEN> 274,914
<PROVISION-CURRENT> 0<F1>
<PROVISION-PRIOR> 0<F1>
<PAYMENTS-CURRENT> 0<F1>
<PAYMENTS-PRIOR> 0<F1>
<RESERVE-CLOSE> 302,716
<CUMULATIVE-DEFICIENCY> 0<F1>
<FN>
<F1>Available on annual basis only.
</FN>
</TABLE>