<TABLE> <S> <C>
<PAGE>
<ARTICLE> 7
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM THE
FINANCIAL STATEMENTS CONTAINED IN THE FORM 10-Q FOR THE PERIOD ENDED JUNE 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> 6-MOS
<FISCAL-YEAR-END> DEC-31-2000
<PERIOD-START> JAN-01-2000
<PERIOD-END> JUN-30-2000
<DEBT-HELD-FOR-SALE> 67,960
<DEBT-CARRYING-VALUE> 288,218
<DEBT-MARKET-VALUE> 285,405
<EQUITIES> 280,355
<MORTGAGE> 0
<REAL-ESTATE> 0
<TOTAL-INVEST> 692,092
<CASH> 0
<RECOVER-REINSURE> 223,587
<DEFERRED-ACQUISITION> 41,471
<TOTAL-ASSETS> 1,207,106
<POLICY-LOSSES> 511,407
<UNEARNED-PREMIUMS> 200,933
<POLICY-OTHER> 0
<POLICY-HOLDER-FUNDS> 0
<NOTES-PAYABLE> 78,119
0
0
<COMMON> 12,805
<OTHER-SE> 284,610
<TOTAL-LIABILITY-AND-EQUITY> 1,207,106
110,830
<INVESTMENT-INCOME> 14,022
<INVESTMENT-GAINS> (87)
<OTHER-INCOME> 0
<BENEFITS> 59,676
<UNDERWRITING-AMORTIZATION> 35,895
<UNDERWRITING-OTHER> 8,920
<INCOME-PRETAX> 18,278
<INCOME-TAX> 4,776
<INCOME-CONTINUING> 13,502
<DISCONTINUED> 0
<EXTRAORDINARY> 0
<CHANGES> 0
<NET-INCOME> 13,502
<EPS-BASIC> 1.37
<EPS-DILUTED> 1.36
<RESERVE-OPEN> 274,914
<PROVISION-CURRENT> 0<F1>
<PROVISION-PRIOR> 0<F1>
<PAYMENTS-CURRENT> 0<F1>
<PAYMENTS-PRIOR> 0<F1>
<RESERVE-CLOSE> 287,820
<CUMULATIVE-DEFICIENCY> 0<F1>
<FN>
<F1>Available on an annual basis only
</FN>
</TABLE>