A public access network operating in conjunction-with existing telecommunication lines to permit a caller holding a machine-readable credit card to make calls from any local station included in the network without having to deposit coins and without human intervention. The network is constituted by a management and master control central linked to a group of satellites installed at different locations, such as airport. terminals. At every installation, the satellite services a plurality of local telephone stations each provided with a standard telephone set, a card reader adapted to scan the caller's credit card to derive thereform a digital signal identifying the card, its number and expiration date, this signal being applied to a local processor to determine whether the card is acceptable to the network. If the card is rejected, the call is terminated, and if accepted, the card data is then transferred from the local processor to a verifying processor at the satellite to test the card number against a stored table of invalid numbers. If the card passes this test the local processor is so advised, the processor then activating the telephone set to permit the caller to dial. The number dialed is received by an intelligent switch at the satellite which connects the set to an appropriate transmission line to put the call through. Central functions not only is to update the invalid card tables in the satellites and to manage the operation of the intelligent switches, but also to extract thereform the details of calls made from the local stations and the related credit card data to generate a billing record for submission to the credit card companies.