Abstract: A temporary phone number system completes telephone calls only for non-expired telephone numbers. A user terminal makes a phone call to a subscriber terminal through a network having server. The subscriber terminal is associated with an IP address located at the server. A dynamic database of telephone numbers that ring the subscriber terminal resides at the IP address on the server. At least one number in the database expires at a selected time so that the call is completed only if the number input into the user terminal is not expired. Methods and computer-readable media containing instructions for performing the methods of the temporary phone number system are described.