<TABLE> <S> <C>

<PAGE>
<ARTICLE> 7
<LEGEND>
This schedule contains summary financial information extracted from the
financial statements contained in Form 10-K for the fiscal year ended December
31, 1998 for PMA Capital Corporation and is qualified in its entirety by
reference to such statements.
</LEGEND>
<MULTIPLIER> 1,000
       
<S>                             <C>                                                
<PERIOD-TYPE>                   YEAR                                               
<FISCAL-YEAR-END>                          DEC-31-1998                             
<PERIOD-START>                             JAN-01-1998                              
<PERIOD-END>                               DEC-31-1998                              
<DEBT-HELD-FOR-SALE>                         1,827,354                                            
<DEBT-CARRYING-VALUE>                                0                                            
<DEBT-MARKET-VALUE>                                  0                                             
<EQUITIES>                                          17                                            
<MORTGAGE>                                           0                                             
<REAL-ESTATE>                                        0                                             
<TOTAL-INVEST>                               2,325,409                                            
<CASH>                                           2,562                                            
<RECOVER-REINSURE>                             610,291                                            
<DEFERRED-ACQUISITION>                          51,115                                            
<TOTAL-ASSETS>                               3,460,718                                            
<POLICY-LOSSES>                              1,940,895                                            
<UNEARNED-PREMIUMS>                            227,945                                            
<POLICY-OTHER>                                       0                                             
<POLICY-HOLDER-FUNDS>                           10,700                                            
<NOTES-PAYABLE>                                163,000                                            
<PREFERRED-MANDATORY>                                0                                             
<PREFERRED>                                          0                                             
<COMMON>                                       122,214                                            
<OTHER-SE>                                     389,266                                          
<TOTAL-LIABILITY-AND-EQUITY>                 3,460,718                                            
<PREMIUMS>                                     466,715                                            
<INVESTMENT-INCOME>                            120,125                                            
<INVESTMENT-GAINS>                              21,745                                            
<OTHER-INCOME>                                  14,896                                            
<BENEFITS>                                     352,671                                            
<UNDERWRITING-AMORTIZATION>                    110,837                                            
<UNDERWRITING-OTHER>                            89,895                                            
<INCOME-PRETAX>                                 55,069                                            
<INCOME-TAX>                                    10,335                                            
<INCOME-CONTINUING>                                  0                                             
<DISCONTINUED>                                       0                                             
<EXTRAORDINARY>                                      0                                           
<CHANGES>                                            0                                             
<NET-INCOME>                                    44,734                                            
<EPS-PRIMARY>                                     1.89                                       
<EPS-DILUTED>                                     1.82                                       
<RESERVE-OPEN>                               1,670,903<F1>                                    
<PROVISION-CURRENT>                            373,098                                        
<PROVISION-PRIOR>                             (46,515)<F2>                                   
<PAYMENTS-CURRENT>                              96,658                                        
<PAYMENTS-PRIOR>                               362,186                                        
<RESERVE-CLOSE>                              1,347,194 <F1><F3>                               
<CUMULATIVE-DEFICIENCY>                        (46,515)                                        
        
<FN>
<F1>  Reserve balance is shown net of reinsurance receivables on unpaid losses
      and LAE
<F2>  Excludes impact of accretion of prior years discount of $26,088.
<F3>  Reserves of $217,536 were transferred to a third party as the result of a
      sale of a subsidiary.
</FN>

</TABLE>