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 calling code 1. Some North American countries, most notably Mexico, do not participate in the NANP.
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, reachable by a system of destination code routing. Telephone numbering plans are defined in each of the administrative regions of the public switched telephone network (PSTN) and in private telephone networks.
Area codes 201 and 551 are telephone area codes in the North American Numbering Plan in the U.S. State of New Jersey. Area code 201 was the area code assigned to the entire state of New Jersey in 1947, when the North American area code system was formulated. After splits in 1958, 1991 and 1997, it covers the northeasternmost portion of the state, including most of Hudson and Bergen counties, bordering the Hudson River and New York City. Major cities in the numbering plan area include Bayonne, Jersey City, Hoboken, Hackensack, Secaucus and Englewood. Area code 551 is an overlay code to the same numbering plan area that was installed in 2001.
Area codes 415 and 628 are telephone area codes in the North American Numbering Plan (NANP) for the city of San Francisco and its northern suburbs in Marin County, and the northeast corner of San Mateo County. Area code 415 was one of the eighty-six original North American area codes established in 1947, but modified in geographic configuration later. Area code 628 was assigned in 2015 to form an overlay in that numbering plan area in mitigation of central office prefix exhaustion.
Area codes 508 and 774 are telephone area codes in the North American Numbering Plan (NANP) for the U.S. state of Massachusetts. The numbering plan area comprises south-central and most of southeastern Massachusetts. It includes Worcester, Outer south and southwest Greater Boston, as well as Fall River, New Bedford, Cape Cod, Martha's Vineyard, and Nantucket.
Area code 914 is the telephone area code in the North American Numbering Plan (NANP) for Westchester County, New York.
Area codes 310 and 424 are telephone area codes in the North American Numbering Plan (NANP) for the U.S. state of California. The numbering plan area includes the West Los Angeles and South Bay areas of Los Angeles County, a small portion of Ventura County, and Santa Catalina Island, which is located 26 miles (42 km) south.
North American telephone area code 262 covers much of Southeastern Wisconsin, and was created on September 25, 1999, when it was split from area code 414. It covers most of the suburbs of Milwaukee, but not Milwaukee County itself.
Area code 516 is a telephone area code of the North American Numbering Plan (NANP) in the U.S. state of New York. The numbering plan area (NPA) comprises the Nassau County portion of Long Island.
Area codes 718, 347, and 929 are telephone area codes in the North American Numbering Plan (NANP) for the boroughs of New York City of the Bronx, Brooklyn, Queens, and Staten Island, as well as the Marble Hill section of Manhattan. They are part of a larger overlay plan with area code 917, which comprises all of New York City.
Area codes 514 and 438 are telephone area codes of the North American Numbering Plan (NANP) for Montreal and most of its on-island suburbs, specifically the Island of Montreal and Île Perrot in the Canadian province of Quebec.
Area codes 402 and 531 are telephone area codes in the North American Numbering Plan (NANP) for eastern Nebraska. Area code 402 was one of the original area codes created in 1947, when it was assigned to the entire state. After splitting the numbering plan area (NPA) in 1954, when the numbering plan area (NPA) was reduced to roughly just the eastern half, the North American Numbering Plan Administrator authorized an overlay plan for which area code 531 was added to the same service area in 2011.
Area codes 717 and 223 are telephone area codes which serve South Central Pennsylvania and the Susquehanna Valley. They cover the Harrisburg, Lancaster and York metropolitan areas as well as most of the area generally known as Pennsylvania Dutch Country—
Area code 412 is a telephone area code in the North American Numbering Plan (NANP) for the Commonwealth of Pennsylvania. The numbering plan area (NPA) comprises the city of Pittsburgh, most of surrounding Allegheny County, and small portions of Washington and Westmoreland counties. The area code was one of the original North American area codes created in 1947, when it was assigned to the entire southwestern corner of the state.
Area code 904 is the telephone area code in use for most of the First Coast (northeast) region of the state of Florida, including all of the metropolitan area of Jacksonville. It includes all of Duval County, St. Johns County, Nassau County, and Baker County, and almost all of Clay County.
Area code 513 is a telephone area code in the North American Numbering Plan (NANP) for the southwest of the U.S. state of Ohio, including Cincinnati and surrounding cities, such as Forest Park, Hamilton, Lebanon, West Chester, Mason, Maineville, Middletown, Milford, Norwood, Oxford, Harrison, Cleves, Miamitown, and Trenton.
Area codes 309 and 861 are telephone area codes in North American Numbering Plan (NANP) for the west-central part of the U.S. state of Illinois. Cities in the numbering plan area include Bloomington, Canton, East Moline, East Peoria, Galesburg, Kewanee, Macomb, Minonk, Moline, Morton, Normal, Pekin, Peoria, Rock Island, Silvis, and many smaller communities within the western part of central Illinois.
Area codes 703 and 571 are the North American Numbering Plan telephone area codes for Northern Virginia, including the independent cities of Alexandria, Fairfax, Falls Church, Manassas, and Manassas Park, as well as all of Arlington and Fairfax counties and parts of Fauquier, Loudoun, and Prince William counties. Area code 703 was created as one of the original 86 North American area codes in October 1947, and originally served the entire Commonwealth of Virginia. Area code 571 was created on March 1, 2000, to form an overlay plan with 703.
Area codes 503 and 971 are telephone area codes in the North American Numbering Plan (NANP) for the northwestern region of the U.S. state of Oregon. The numbering plan area (NPA) comprises the cities of Portland, Salem, and Astoria. Area code 503 was one of the original North American area codes of 1947, assigned to the entire state until 1995, when its extent was reduced to the northwest corner. Area code 971 was assigned to the service area in stages, completed in 2008, to form an overlay in the area with ten-digit dialing.
Area codes 809, 829, and 849 are telephone area codes in the North American Numbering Plan (NANP) for the Dominican Republic. As all NANP members, the Dominican Republic uses country code 1, and has similar dialing procedures for dialing the ten-digit national telephone numbers, which consist of the area code, a three-digit central office code, and a four-digit line number. The three area codes of the country are organized as an overlay plan for a single numbering plan area (NPA), comprising the entire country. Thus, ten-digit dialing is mandatory.
