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 telephone country code 1. Some North American countries, most notably Mexico, do not participate in the NANP.
Area codes 314 and 557 are telephone area codes in the North American Numbering Plan (NANP) in the U.S. state of Missouri, serving the city of St. Louis and most of its inner-ring suburbs in neighboring St. Louis County. The numbering plan area is bordered to the west by area code 636, which serves St. Louis' outer suburbs to the west, south, and north. Across the Mississippi River to the east, 314 is adjacent to area code 618, which serves southern Illinois and most of Metro East. Area code 557 was added to the 314 numbering plan area on August 12, 2022, to form an overlay numbering plan.
Area codes 850 and 448 are telephone area codes in the North American Numbering Plan for the Florida Panhandle, including Pensacola, Tallahassee and Panama City. Area code 850 was created in 1997 in a split from 904, and area code 448 was assigned as a second code to the same area in an overlay plan in 2019, and mandatory ten-digit local calling began in May 2021.
Area codes 954 and 754 are the telephone area codes in the North American Numbering Plan (NANP) for Broward County, Florida. Notable cities in the numbering plan area are Fort Lauderdale, Plantation, Hollywood, Parkland, Sunrise, Pompano Beach, Coral Springs, Deerfield Beach, Davie, Weston, Dania Beach, Oakland Park and Pembroke Pines.
In telecommunications, an area code overlay complex is a telephone numbering plan that assigns multiple area codes to a geographic numbering plan area (NPA). Area code overlays are implemented in territories of the North American Numbering Plan (NANP) to mitigate exhaustion of central office codes in growth areas. The method has been in use since 1992, and has been the preferred and exclusive method of relief since 2007.
Ten-digit dialing is a telephone dialing procedure in the countries and territories that are members of the North American Numbering Plan (NANP). It is the practice of including the area code of a telephone number when dialing to initiate a telephone call. When necessary, the ten-digit number may be prefixed with the trunk code 1, which is referred to as 1+10-digit dialing or national format.
Area codes 561 and 728 are telephone area codes in the North American Numbering Plan (NANP) for Palm Beach County in the U.S. state of Florida. 561 was created on May 13, 1996, in a split of area code 407. The numbering plan area (NPA) comprises nearly every major city in the county, the largest of which being West Palm Beach, Boca Raton, Wellington, Boynton Beach, Jupiter, Delray Beach, and Belle Glade. On March 10, 2023, area code 728 was added to the same numbering plan area to form an all-services distributed overlay.
Area codes 920 and 274 are telephone area codes in the North American Numbering Plan (NANP) for a large area of eastern Wisconsin. Area code 920 was created on July 26, 1997, in a split of area code 414, one of the original North American area codes of 1947. 274 was added to the same numbering plan area (NPA) on May 5, 2023 to create an area code overlay.
Area codes 909 and 840 are telephone area codes in the North American Numbering Plan for the far-eastern part of Los Angeles County and southwestern San Bernardino County in the U.S. state of California. Area code 909 was created on November 14, 1992 in an area code split of 714, and 840 was added to the numbering plan area to form an overlay complex effective February 23, 2021.
Area codes 876 and 658 are telephone area codes in the North American Numbering Plan (NANP) for Jamaica.
Area code 435 is a telephone area code in the North American Numbering Plan (NANP) for most of the U.S. state of Utah. The numbering plan area excludes the region of the Wasatch Front, which comprises the Salt Lake City, Ogden, and Provo metropolitan areas in northern Utah, and is served by area codes 801 and 385. Area code 435 was created in 1997 in a split of 801.
Area codes 704 and 980 are telephone area codes in the North American Numbering Plan (NANP) for Charlotte and all or part of 12 surrounding counties in south-central North Carolina. Other major cities in the service area are Gastonia, Kannapolis, Concord, Mooresville, Salisbury, Statesville, and Shelby. The South Carolina side of the Charlotte metropolitan area is part of area codes 803 and 839. Area code 704 is one of the original area codes assigned to numbering plan areas (NPAs) by AT&T in October 1947. Area code 980 was added in an overlay numbering plan in 2000.
Area codes 304 and 681 are telephone area codes in the North American Numbering Plan (NANP) for the entirety of the U.S. state of West Virginia. The numbering plan area was established in October 1947 with area code 304, as one of the eighty-six original North American area codes. Area code 681 was added to the same area in an overlay plan that took effect on March 28, 2009.
Area code 904 is a telephone area code in the North American Numbering Plan for most of the First Coast (northeast) region of the U.S. state of Florida. The numbering plan ara comprises most 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 904 was created in an area code split of area code 904 in 1965. In 2024, the numbering plan area is scheduled for conversion to an overlay complex with a second area code, 324, to mitigate central office code exhaustion and provide additional telephone numbers in the area.
Area codes 303, 720 and 983 are telephone area codes in the North American Numbering Plan for the north-central portion of the U.S. state of Colorado. The numbering plan area comprises Denver and Boulder, as well as their surrounding suburbs, including Lakewood, Littleton, Longmont, Broomfield, Aurora, and Castle Rock. Area code 303 is the original area code, while area codes 720 and 983 were added to form an overlay complex for the area, meaning that the same geographic service area is served by all area codes and that ten-digit dialing is required for all calls made within the service area.
Area code 816 is a telephone area code in the North American Numbering Plan (NANP) for Kansas City, St. Joseph, and all or part of 15 surrounding counties in northwestern Missouri. The numbering plan area originally comprised most of the northern and western two-thirds of the state, bordering with Arkansas, Illinois, Iowa, Kansas, Nebraska, and Oklahoma, but has been reduced to a ribbon bordering Kansas. 816 is one of the original 86 area codes created in 1947.
Area code 270 is a telephone area code in the North American Numbering Plan (NANP) for the Commonwealth of Kentucky's western and south central counties. Area code 270 was split from area code 502 on April 19, 1999. Planning for the introduction of a second area code for the region, area code 364, was assigned in 2007. After several years of delay in activation, it was announced in December 2012 that the two area codes would be configured in an overlay plan in August 2013. Mandatory ten-digit dialing began on February 1, 2014. Numbers of the new area code were made available for assignment on March 3, 2014.
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.
