The
North American Numbering Plan
The North American Numbering Plan (NANP) is a telephone numbering plan for twenty-five regions in twenty countries, primarily in North America and the Caribbean. This group is historically known as World Zone 1 and has the international callin ...
(NANP) divides the territories of its members into geographic numbering plan areas (NPAs). Each NPA is identified by one or more numbering plan area codes (''NPA codes'', or ''
area code
A telephone numbering plan is a type of numbering scheme used in telecommunication to assign telephone numbers to subscriber telephones or other telephony endpoints. Telephone numbers are the addresses of participants in a telephone network, rea ...
s''), consisting of three digits that are prefixed to each local telephone number having seven digits. Numbering plan areas may be assigned multiple area codes to provide adequate numbering resources, in which case the local numbering plan is called an
overlay
Overlay may refer to:
Computers
*Overlay network, a computer network which is built on top of another network
*Hardware overlay, one type of video overlay that uses memory dedicated to the application
*Another term for exec, replacing one process ...
. Area codes are also assigned for non-geographic purposes. The rules for numbering NPAs do not permit the digits ''0'' and ''1'' as the leading digit, which also applies for central office codes.
[AT&T (1955) ''Notes on Distance Dialing''] NPAs with ''9'' as the second digit are reserved for future format expansion. Area codes with two identical trailing digits are considered easily recognizable codes (ERC), which are reserved, or used for systemwide services.
Area codes in numerical order
200–299
300–399
400–499
500–599
600–699
700–799
800–899
900–999
Area codes by country, state, province, and regions
Future area codes are emphasized in ''italics''.
United States
Canada
Caribbean and Atlantic islands
U.S. Pacific territories
Non-geographic area codes
Summary table
Assignment activities by year
See also
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Bell System
The Bell System was a system of telecommunication companies, led by the Bell Telephone Company and later by the American Telephone and Telegraph Company (AT&T), that dominated the telephone services industry in North America for over one hundr ...
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List of country calling codes
Country calling codes or country dial-in codes are telephone number prefixes for reaching telephone subscribers in the networks of the member countries or regions of the International Telecommunication Union (ITU). The codes are defined by the ...
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List of future North American area codes
This is a list of future area codes in the North American Numbering Plan (NANP) in the planning stages for relief of central office code exhaustion in the given numbering plan areas (NPAs). The dates are subject to change during implementation as p ...
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Original North American area codes
The original North American area codes were established by the American Telephone & Telegraph Company (AT&T) in 1947, following the demonstration of regional Operator Toll Dialing during the World War II period. The program had the goal of speedin ...
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Telephone numbers in the Americas
All countries in the Americas use codes that start with "5" except for: Canada, the United States and some Caribbean countries under the North American Numbering Plan use country calling code 1 and Greenland and Aruba with a country calling code st ...
References
{{DEFAULTSORT:North American Numbering Plan area codes
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Canada communications-related lists
Communication-related lists
North American Numbering Plan
United States communications-related lists