Abstract: Small communication systems do not have a sufficiently large memory to store the vast amount of data required to determine the cost of interstate telephone calls using the conventional method. The disclosed telephone call cost establishing method and apparatus compresses the amount of data required by supplying a set of coordinates for a central point in each area code. The cost of an interstate call to any central office in an area code is then determined using the coordinates of the central point for that area code. Additionally, certain types of calls are priced using a predetermined price code stored in a variety of tables such as toll call allowed, frequently called numbers, personal line and facility tables.