- A leading ‘1’ is included in the international call sequence. It doubles as a trunk prefix for domestic long distance calls.
- A leading '+' in the phone number means 'dial your country's exit code'.
- Calling from a mobile phone: dial from on the country where you're currently located.
- Calling from a VoIP or satellite phone: dial from on the country where the phone is registered.
Use the same call sequence.
When calling a mobile phone user, dial to the country where the mobile phone is registered, regardless of where the person is roaming.
Use the same call sequence.
When calling a VoIP phone user, dial to the country where the VoIP phone is registered, regardless of where the person is roaming.
The United States does not have a country-specific satellite phone system.
Most satellite phones operate on their country code – calls to these satellite phones follow their own call sequence.
Use the same call sequence.
‘1’ is used as a long distance trunk prefix (it also doubles as the country code) to call long distance.
Most phone calls within the same metropolitan area (even across state lines) are within the local calling area. Calls to another metropolitan area are to a different local calling area. Local calling areas can overflow into neighboring states and area codes.
When unsure of which call sequence to use, first try the long distance sequence. The phone system is designed to reply with a message if the call is improperly dialed, and if the local call sequence should have been dialed the local rate will be charged for the call.
Local calling (within a local calling area) – seven-digit dialing (including to and from a mobile phone)
Regions with seven-digit dialing do not have any overlapping area codes (there is only one area code that can represent that region).
A call across a long distance even within a non-overlapping area code needs to be dialed with the leading ‘1’ and ten digit sequence, not the local calling sequence. (see long distance calling)
If it is not certain if the region is a seven digit or ten digit dialing region, the ten digit sequence will still work.
To dial the seven-digit sequence, dial only the local seven-digit phone number.
|local phone number|
Local calling (within a local calling area) – ten-digit dialing (including to and from a mobile phone)
The ten digit dialing sequence is used to call to a phone number in the same local calling area when the region has more than one area codes representing the region. It can also be used when a neighboring area code is within the local calling area.
|three digits||seven digits|
|area code||local phone number|
To call to a different calling area, dial the trunk prefix ‘1’ (it also doubles as the international country code for countries in the NANP), followed by the area code, followed by the local phone number.
|1||three digits||seven digits|
|trunk prefix / country code||area code||local phone number|
American phone numbers are ten digits (eleven including a leading ‘1’ that doubles as both the country code for the NANP and a long distance trunk prefix).
The first three digits are an area code representing a geographic part of the country. In many cities area codes overlap. The area code is often listed in brackets ().
Digits four to seven represent an exchange within the area code. Typically the exchange signifies a physical location or that the phone numbers starting with it are mobile phone numbers.
Mobile numbers and VoIP numbers are intermixed with land-line phone numbers. There are no mobile-specific or VoIP-specific area codes. Some exchanges within the area code may be designated mobile or VoIP, however, there is no consistent pattern.
America shares country code +1 with the regions of the NANP (including Canada, most of the regions of the Caribbean, and U.S. territories in the Pacific). Calls to countries within the NANP are dialed the same as a domestic U.S. long distance phone call, although international rate charges may apply.
The Metropolitan Museum of Modern Art lists its phone number in New York City as (1) 212-535-7710.
|country code for the United States as well as the American trunk prefix||area code for New York City||local phone number within New York City|
Local example – calling from another location in New York City
To call within a local calling area, dial the area code and the local phone number. There is no need to dial the trunk prefix/country code ‘1’.
|area code for New York City||local phone number within New York City|
Long distance example – calling from Los Angeles, United States (on the other side of the country)
To call long distance dial the long distance trunk prefix/country code ‘1’, then the area code, then the local phone number.
|long distance trunk prefix||area code for New York City||local phone number within New York City|
International example – calling from Canada or another country of the NANP (most of the Caribbean and U.S. territories in the Pacific)
To call from another NANP country dial the trunk prefix/country code of ‘1’, then the area code, then the local phone number. The call sequence is the same as a domestic long distance phone call within the United States or Canada, however, international call rates may apply.
|long distance trunk prefix||area (geographic) code for New York City||local phone number in New York|
International example – calling from a country outside of the NANP (Canada, most of the Caribbean, and U.S. Territories in the Pacific)
To call from a country from outside the North American Numbering Plan, dial the exit code of the country you’re calling from, then the NANP country code/trunk prefix of ‘1’, then the area code, then the local phone number.
|exit code||1||212||535 7710|
|exit code of the country the call is dialed from||country code for the North American Numbering Plan||area (geographic) code for New York City||local phone number in New York|
… to another country in the North American Numbering Plan (NANP)
Dial the phone call starting with the trunk prefix/country code of ‘1’, then the area code and local phone number.
… to all other regions of the world
‘011’ is used as an exit code when dialing an international phone call from the United States to a location outside the NANP calling region (the United States, Canada, most regions of the Caribbean, and U.S. Territories in the Pacific).
- National NANPA – The North American Numbering Plan Administration. Telecommunications numbering system regulator for numbering administration across the North American Numbering Plan.
- FCC (Federal Communications Commission) – America’s telephone systems regulator.
- NCTA (National Cable and Telecommunications Association) – Telecommunications association for the United States.
- ITU (International Telecommunications Union) – United Nations specialized agency for information and communications technologies.
- International Telecommunications Union – DIALLING PROCEDURES (INTERNATIONAL PREFIX, NATIONAL (TRUNK) PREFIX AND NATIONAL (SIGNIFICANT) NUMBER) (IN ACCORDANCE WITH ITU-T RECOMMENDATION E.164 (11/2010)) – A collection of dialing procedures for all countries and regions of the world. Retrieved 16 September 2016.
- International Telecommunications Union – USA (country code +1) National Numbering Plan – Details of the USA’s and the NANPA’s telephone numbering plan as submitted to the ITU. Retrieved 28 November 2016.
- Wikipedia – North American Numbering Plan – Wikipedia entry for telephone number data for the United States and the North American Numbing Plan. Includes specific number ranges for each city as well as detail on calling procedures.
- BT – The Phonebook – USA – Entry for the United States in the British Telecom international directory.