This page contains the Federal Communications Commission regulations relating to telephone numbering, excerpted from the Code of Federal Regulations, Title 47, Volume 3, Part 52, Subpart B (pages 52-55), revised as of October 1, 1997, with some formatting added. While the text displayed below is believed correct, LincMad Consulting provides no warranty.

If you require an authoritative copy of these regulations, please contact the U.S. Government Printing Office, Code of Federal Regulations online, or go directly to 47 CFR 52 (B).

Part 52—Numbering

Subpart B—Administration

Source: 61 FR 47353, Sept. 6, 1996, unless otherwise noted.

Sec. 52.7 Definitions.

As used in this subpart:

1. Area code or numbering plan area (NPA). The term “area code or numbering plan area” refers to the first three digits (NXX) of a ten-digit telephone number in the form NXX-NXX-XXXX, where N represents any one of the numbers 2 through 9 and X represents any one of the numbers 0 through 9.
2. Area code relief. The term “area code relief” refers to the process by which central office codes are made available when there are few or no unassigned central office codes remaining in an existing area code and a new area code is introduced.
3. Central office (CO) code. The term “central office code” refers to the second three digits (NXX) of a ten-digit telephone number in the form NXX-NXX-XXXX, where N represents any one of the numbers 2 through 9 and X represents any one of the numbers 0 through 9.
4. Central office (CO) code administrator. The term “central office code administrator” refers to the entity or entities responsible for managing central office codes in each area code.
5. North American Numbering Plan Administrator (NANPA). The term “North American Numbering Plan Administrator” refers to the entity or entities responsible for managing the NANP.

Sec. 52.9 General requirements.

1. To ensure that telecommunications numbers are made available on an equitable basis, the administration of telecommunications numbers shall, in addition to the specific requirements set forth in this subpart:
   1. Facilitate entry into the telecommunications marketplace by making telecommunications numbering resources available on an efficient, timely basis to telecommunications carriers;
   2. Not unduly favor or disfavor any particular telecommunications industry segment or group of telecommunications consumers; and
   3. Not unduly favor one telecommunications technology over another.
2. If the Commission delegates any telecommunications numbering administration functions to any State or other entity pursuant to 47 U.S.C. 251(e)(1), such State or entity shall perform these functions in a manner consistent with this part.

Sec. 52.11 North American Numbering Council.

The duties of the North American Numbering Council (NANC), may include, but are not limited to:

1. Advising the Commission on policy matters relating to the administration of the NANP in the United States;
2. Making recommendations, reached through consensus, that foster efficient and impartial number administration;
3. Initially resolving disputes, through consensus, pertaining to number administration in the United States;
4. Recommending to the Commission an appropriate entity to serve as the NANPA;
5. Recommending to the Commission an appropriate mechanism for recovering the costs of NANP administration in the United States, consistent with Sec. 52.17;
6. Carrying out the duties described in Sec. 52.25 [Subpart C — Number Portability]; and
7. Carrying out this part as directed by the Commission.

Sec. 52.13 North American Numbering Plan Administrator.

1. The North American Numbering Plan Administrator (NANPA) shall be an independent and impartial non-government entity.
2. The duties of the NANPA shall include, but are not limited to:
   1. Ensuring that the interests of all NANP member countries are considered;
   2. Processing number assignment applications associated with, but not limited to: area codes, N11 codes, carrier identification codes (CICs), “500” central office codes, “900” central office codes, “456” central office codes[*], Signalling System 7 network codes, and Automatic Number Identification Integration Integers (ANI II);
   3. Assigning the numbers and codes described in paragraph (b)(2) of this section;
   4. Maintaining and monitoring administrative number databases;
   5. Assuming additional telecommunications number administration activities, as assigned; and
   6. Ensuring that any action taken with respect to number administration is consistent with this part.

Sec. 52.15 Central Office Code Administration.

1. Central Office Code Administration shall be performed by the NANPA, or another entity or entities, as designated by the Commission.
2. Duties of the entity or entities performing central office code administration may include, but are not limited to:
   1. Processing central office code assignment applications and assigning such codes in a manner that is consistent with this part;
   2. Accessing and maintaining central office code assignment databases;
   3. Contributing to the CO Code Use Survey (COCUS), an annual survey that describes the present and projected use of CO codes for each NPA in the NANP; [[Page 54]]
   4. Monitoring the use of central office codes within each area code and forecasting the date by which all central office codes within that area code will be assigned; and
   5. Planning for and initiating area code relief, consistent with Sec. 52.19.
3. Any telecommunications carrier performing central office code administration:
   1. Shall not charge fees for the assignment or use of central office codes to other telecommunications carriers, including paging and CMRS providers, unless the telecommunications carrier assigning the central office code charges one uniform fee for all carriers, including itself and its affiliates; and
   2. Shall, consistent with this subpart, apply identical standards and procedures for processing all central office code assignment requests, and for assigning such codes, regardless of the identity of the telecommunications carrier making the request.

Sec. 52.17 Costs of Number Administration.

All telecommunications carriers in the United States shall contribute on a competitively neutral basis to meet the costs of establishing numbering administration.

1. For each telecommunications carrier, such contributions shall be based on the gross revenues from the provision of its telecommunications services.
2. The contributions in paragraph (a) of this section shall be based on each contributor’s gross revenues from its provision of telecommunications services reduced by all payments for telecommunications services and facilities that have been paid to other telecommunications carriers.

Sec. 52.19 Area Code Relief.

1. State commissions may resolve matters involving the introduction of new area codes within their states. Such matters may include, but are not limited to: Directing whether area code relief will take the form of a geographic split, an overlay area code, or a boundary realignment; establishing new area code boundaries; establishing necessary dates for the implementation of area code relief plans; and directing public education and notification efforts regarding area code changes.
2. State commissions may perform any or all functions related to initiation and development of area code relief plans, so long as they act consistently with the guidelines enumerated in this part, and subject to paragraph (b)(2) of this section. For the purposes of this paragraph, initiation and development of area code relief planning encompasses all functions related to the implementation of new area codes that were performed by central office code administrators prior to February 8, 1996. Such functions may include: declaring that the area code relief planning process should begin; convening and conducting meetings to which the telecommunications industry and the public are invited on area code relief for a particular area code; and developing the details of a proposed area code relief plan or plans.
   1. The entity or entities designated by the Commission to serve as central office code administrator(s) shall initiate and develop area code relief plans for each area code in each state that has not notified such entity or entities, pursuant to paragraph (b)(2) of this section, that the state will handle such functions.
   2. Pursuant to paragraph (b)(1) of this section, a state commission must notify the entity or entities designated by the Commission to serve as central office code administrator(s) for its state that such state commission intends to perform matters related to initiation and development of area code relief planning efforts in its state. Notification shall be written and shall include a description of the specific functions the state commission intends to perform. Where the NANP Administrator serves as the central office code administrator, such notification must be made within 120 days of the selection of the NANP Administrator.
3. New area codes may be introduced through the use of:
   1. A geographic area code split, which occurs when the geographic area served by an area code in which there are few or no central office codes left [[Page 55]] for assignment is split into two or more geographic parts;
   2. An area code boundary realignment, which occurs when the boundary lines between two adjacent area codes are shifted to allow the transfer of some central office codes from an area code for which central office codes remain unassigned to an area code for which few or no central office codes are left for assignment; or
   3. An area code overlay, which occurs when a new area code is introduced to serve the same geographic area as an existing area code, subject to the following conditions:
      1. No area code overlay may be implemented unless all central office codes in the new overlay area code are assigned to those entities requesting assignment on a first-come, first-serve basis, regardless of the identity of, technology used by, or type of service provided by that entity. No group of telecommunications carriers shall be excluded from assignment of central office codes in the existing area code, or be assigned such codes only from the overlay area code, based solely on that group’s provision of a specific type of telecommunications service or use of a particular technology;
      2. No area code overlay may be implemented unless there exists, at the time of implementation, mandatory ten-digit dialing for every telephone call within and between all area codes in the geographic area covered by the overlay area code; and
      3. No area code overlay may be implemented unless every telecommunications carrier, including CMRS providers, authorized to provide telephone exchange service, exchange access, or paging service in that NPA 90 days before introduction of the new overlay area code, is assigned during that 90 day period at least one central office code in the existing area code.

Title 47 – Telegraphs, Telephones, and Radiotelegraphs
Chapter 5 – Wire or Radio Communication
Subchapter II – Common Carriers
Part II - Development of Competitive Markets
Sec. 251. Interconnection
(e) Numbering administration
(1) Commission authority and jurisdiction

The Commission shall create or designate one or more impartial entities to administer telecommunications numbering and to make such numbers available on an equitable basis. The Commission shall have exclusive jurisdiction over those portions of the North American Numbering Plan that pertain to the United States. Nothing in this paragraph shall preclude the Commission from delegating to State commissions or other entities all or any portion of such jurisdiction.

[For an authoritative copy of this statute, please consult the U.S. House of Representatives, U.S. Code on the web, 47 USC 251.]

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