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 with 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 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 code 414 is a telephone area code of the North American Numbering Plan for the area around and including the city of Milwaukee in the state of Wisconsin.
Area codes 708 and 464 are telephone area codes in the North American Numbering Plan (NANP) for the southern and western suburbs of Chicago in the U.S. state of Illinois. The numbering plan area comprises most of western and southern Cook County, and eastern and southern Will County.
Area code 345 is the local telephone area code of the Cayman Islands. The 345 area code was created during a split from the original 809 area code which began permissive dialing on 1 September 1996 and ended 31 August 1997.
Area code 928 is a telephone area code in the North American Numbering Plan for the U.S. state of Arizona. The numbering plan area comprises the northern, eastern, and western portions of the state. It includes Beaver Dam, the Grand Canyon, Flagstaff, Holbrook, Lake Havasu City, Littlefield, Kingman, Prescott, Sedona, Wickenburg, Winslow and Yuma, and also serves most of Greenlee County, some areas on the western and northern fringes of the Phoenix metropolitan area, such as Lake Pleasant Regional Park in Peoria, and the Arizona portion of the Navajo Nation.
The dialling plan for mobile networks and new landline operators is closed; all subscriber numbers must be dialled in full. For landline numbers starting with 02, the dialling plan used to be open; the trunk digit and area code could be omitted if the caller was in the same area code as the callee. However, starting May 3, 2008, all landline numbers must be dialled in full.
Area codes 678, 470, and 943 are telephone area codes in the North American Numbering Plan (NANP) for the U.S. State of Georgia in the Atlanta metropolitan area. The area codes are assigned in an overlay plan to a combined numbering plan area (NPA) consisting of 404 and 770.
Area codes 814 and 582 are telephone area codes in the North American Numbering Plan (NANP) for the northwestern and central portions of the Commonwealth of Pennsylvania. Cities served by the area code include Altoona, Bradford, DuBois, Erie, Meadville, Oil City, Titusville, Johnstown, St. Marys, and Warren as well as the boroughs of State College, Brockway, Clearfield, Huntingdon, Mount Union, Bedford, Clarion, Punxsutawney, Tyrone, Ebensburg, Coudersport, Ridgway and Brookville. Area code 814 is the original area code assigned to the numbering plan area in 1947. Area code 582 was activated in the service area as an additional code to form an overlay numbering plan with a starting date of October 3, 2020.
Area code 607 is a telephone area code in the North American Numbering Plan for the U.S. state of New York. It serves parts of its Southern Tier. It was created in 1954 by combining the southern portion of 315 and the eastern portion of 716. Initially, in the late 1940s, area codes with a middle digit of "0" (x0x-xxx-xxxx) were assigned only to jurisdictions covering an entire state. Along with 507 in Minnesota and 606 in Kentucky, 607 was among the first such area codes to be added to a jurisdiction.
Area codes 573 and 235 are telephone area codes in the North American Numbering Plan (NANP) for most of the eastern half of the U.S. state of Missouri outside the immediate St. Louis area, including the state capital of Jefferson City, as well as Columbia, Cape Girardeau, Hannibal, Rolla, and Sikeston. The largest cities are Columbia, home to the University of Missouri, and Jefferson City, the state capital.The numbering plan area (NPA) extends across half of the width of the state, with the northeastern tip near the northeastern corner of the state, the Lake of the Ozarks at the western tip and Doniphan as the southwestern tip. They also serves all of southeastern Missouri and areas adjacent to the Mississippi River. 573 was created on January 7, 1996, in a split of area code 314, which was limited to the St. Louis metropolitan area in Missouri, and 235 was added on March 24, 2024 as part of an overlay complex.
Area code 810 is a telephone area code in the North American Numbering Plan for the east-central part in the U.S. state of Michigan. The numbering plan area (NPA) comprises the cities of Flint, Lapeer, Port Huron, and the southern portion of the Thumb.
Area code 501 is a telephone area code in the North American Numbering Plan (NANP) for central Arkansas, including Little Rock and most of its suburbs. The numbering plan area (NPA) comprises most communities in Cleburne, Conway, Faulkner, Garland, Hot Spring, Lonoke, Perry, Pulaski, Saline, White and Van Buren counties.
Area code 620 covers telephone exchanges in most of southern Kansas. It was created as the result of a split from 316 on February 3, 2001. The area code stretches across the southern half of the state, from the Colorado border in the west to the Missouri border in the east. It completely surrounds 316, which now only serves Wichita and its inner suburbs, making it one of the six pairs of "doughnut area codes" in the numbering plan. Permissive dialing of 316 across southern Kansas continued until November 3, 2001.
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 codes 816 and 975 are telephone area codes in the North American Numbering Plan (NANP) for most of the Missouri side of the Kansas City metropolitan area, the St. Joseph area, 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. The numbering plan area was converted to an overlay complex with area code 975 in 2023.
Area codes 870 and 327 are telephone area codes in the North American Numbering Plan (NANP) for southern, eastern, and most of northern Arkansas. 870 was created on April 14, 1997 in a split from area code 501, Arkansas's original area code of 1947 and 327 was added as part of an overlay complex in 2024.
Area codes 440 and 436 are telephone area codes in the North American Numbering Plan (NANP) for the U.S. state of Ohio, serving the parts of the Greater Cleveland area, surrounding the city of Cleveland, but not the city and most of its inner suburbs.
