Method, apparatus, and system for filtering incoming telephone calls

This invention relates to blocking incoming telephone calls and specifically to an apparatus and method for allowing only a predetermined set of telephone numbers to complete a telephone call thereby blocking access to numbers not within the predetermined set. A method and system for restricting telephone access to a predetermined set of telephone numbers. The method includes comparing the output of a caller ID signal decoder to telephone numbers stored in memory and allowing the telephone call to be completed if there is match between the calling party's number and a number stored in memory. The system consists of connection circuitry to which is connected a caller ID decoder, a number comparator, and an off hook detector. These components interact to restricts calls to only those stored in the number comparator.