North American Numbering Plan (NANP)
The North American Numbering Plan (NANP) is a telephone numbering plan that encompasses 25 distinct regions in twenty countries primarily in North America, including the United States and its territories, Canada, Bermuda, and many Caribbean nations.
Standardized Format: The NANP standardizes telephone number formats in its member countries. Each telephone number under the NANP is a ten-digit number consisting of a three-digit Numbering Plan Area (NPA) code, commonly known as the area code, followed by a seven-digit local number.
Area Codes and Local Numbers: The first three digits (NPA) identify the specific geographic region (area code), and the next three digits (NXX) represent the exchange code within the area, followed by a four-digit subscriber number.
Direct Dialing: The NANP enables direct dialing of long-distance calls within the region, without the need for an operator.
Allocation of Numbers: The NANP Administrator (NANPA) is responsible for the allocation of area codes and management of the numbering plan to ensure the availability of telephone numbers across the region.
International Direct Dialing (IDD): For international calls originating from countries within the NANP, the international dialing prefix is ‘011’.
The North American Numbering Plan facilitates efficient and standardized telephone communications across its member countries and is a key component of the telecommunications infrastructure in the North American region.