Numbering Resources

555 Line Numbers

555 numbers were made available starting in 1994 for the purpose of reaching a wide variety of information services. Although nearly 8,000 555 line numbers were assigned since their availability, these numbers were not placed into service.

In May 2016, the Industry Numbering Committee (INC) determined that the purpose for which this resource was intended had been accommodated by other information/communication technologies. The future of a 555 resource will be determined if a need for the resource is identified and agreed to by INC.

As a result, INC created the 555 NXX Line Number Reference Document (ATIS-0300115) and agreed to sunset the 555 NXX Assignment Guidelines (ATIS-0300048). The FCC approved this decision in September 2016.

All 555 line numbers have been returned to the inventory of NANPA resources. The following 555 line numbers remain in use:

  • 555-1212 Directory Assistance National use
  • 555-4334 Assigned National use

The fictitious, non-working numbers, 555-0100 through 555-0199, will remain reserved for entertainment/advertising.


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