To use a card, you first must dial an access code to connect to the carrier that issued the card. These access codes are usually a toll free number, but some cards (typically those issued by local carriers) allow you to connect just by dialing a zero.

It's worth noting that some payphones may now charge an initial deposit (usually the cost of a local phone call) to use the phone even if you are calling a toll-free number. This new charge is due to deregulation stemming from the Telecom Act of 1996 and started taking effect in late 1997.

Once connected to the system, you then have to take two steps. (The order in which these steps are taken may vary.) One, you enter your account code. This tells the carrier to whom the call should be billed. Two, you dial the telephone number you want to reach.

The bill is later mailed to the card owner.