Abstract: A call management system is disclosed that may interface with an existing PBX or may be utilized as a separate unit. In a preferred embodiment, the call management system includes a tariff data server, a local client computer and one or more line units. The tariff data server holds tariff data of service providers and transmits the tariff data to the local client computer via a communications link. The communications link can include the Internet making the tariff data widely available. Each line unit couples a telephone set to the telephone line provided by the LEC. The local client computer maintains a communications link with each line unit. Each line unit can be coupled to more than one LEC, allowing cost optimizations to take into account the LEC in addition to long distance carriers. The line unit intercepts the dialed digits and transmits them to the local client computer.