Abstract: An apparatus for analyzing telephone billing data to produce augmented billings and reports on calls to classes of telephone numbers selected by the user, such as to calls not on a list of authorized telephone numbers or calls not fulfilling some other predetermined criterion, includes data reading, selecting, and storing means capable of obtaining telephone directory and billing data in machine manipulatable form, comparing means for finding matches between sets of data as well as tracking failures to match, and data combining and outputting means for producing useful reports. External directory information database searching means are provided for matching billing data not matched with the internally stored directory data. Means are also provided for creating a secondary directory of data extracted from previously matched billing data to increase the efficiency of processing of subsequent billing data sets.