<ARTICLE> 5
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM FORM 10-Q
FOR THE THIRD QUARTER ENDED SEPTEMBER 30, 2000 AND IS QUALIFIED IN ITS ENTIRETY
BY REFERENCE TO SUCH FINANCIAL STATEMENTS.
</LEGEND>
<CIK> 0001002531
<NAME> TOLLGRADE COMMUNICATIONS, INC.

                             
<PERIOD-TYPE>                   3-MOS
<FISCAL-YEAR-END>                          DEC-31-2000
<PERIOD-START>                             JUL-02-2000
<PERIOD-END>                               SEP-30-2000
<CASH>                                      33,245,797
<SECURITIES>                                25,305,837
<RECEIVABLES>                               14,947,339
<ALLOWANCES>                                   177,811
<INVENTORY>                                 26,130,850
<CURRENT-ASSETS>                           109,204,905
<PP&E>                                      11,557,845
<DEPRECIATION>                               5,622,091
<TOTAL-ASSETS>                             120,237,614
<CURRENT-LIABILITIES>                        8,840,153
<BONDS>                                              0
<PREFERRED-MANDATORY>                                0
<PREFERRED>                                          0
<COMMON>                                     2,651,606
<OTHER-SE>                                 108,735,905
<TOTAL-LIABILITY-AND-EQUITY>               120,237,614
<SALES>                                     29,787,819
<TOTAL-REVENUES>                            29,787,819
<CGS>                                       10,840,558
<TOTAL-COSTS>                               10,840,558
<OTHER-EXPENSES>                                     0
<LOSS-PROVISION>                                     0
<INTEREST-EXPENSE>                                   0
<INCOME-PRETAX>                             11,399,541
<INCOME-TAX>                                 4,104,000
<INCOME-CONTINUING>                                  0
<DISCONTINUED>                                       0
<EXTRAORDINARY>                                      0
<CHANGES>                                            0
<NET-INCOME>                                 7,295,541
<EPS-BASIC>                                        .57
<EPS-DILUTED>                                      .54