Telephone numbers are omitted from a communications device (200) or line (110b), thereby inhibiting incoming calls. Outgoing calls are permitted on the line or communications device and are facilitated in part by an equipment identifier (122b, 222) used in a telecommunications network. A surrogate telephone number, which may already be assigned to a customer, is used for billing, caller identification and other functions. The equipment identifier is used for maintenance, administration and other functions associated with the communications device or line. A telephone number is temporarily made available to the communications device or line for a predetermined period of time upon request by a user. This advantageously reduces the number of telephone numbers required in a telecommunications network.