Area code 970 is a telephone area code in the North American Numbering Plan (NANP) for most of the western and northern parts of the U.S. state of Colorado. The numbering plan area includes Aspen, Breckenridge, Durango, Estes Park, Fort Collins, Glenwood Springs, Grand Junction, Greeley, Loveland, Silverthorne, Steamboat Springs, and Vail. It was established on April 2, 1995 in an area code split of area code 303, which was retained by the Denver area. [2]
Area code 970 has PCS telephone numbers assigned for the central office code 988 in the Fort Collins exchange. [3] As of October 17, 2020, 988 has been assigned by law as a three-digit code for the National Suicide Prevention Lifeline. To avoid conflicts in switching systems, the Federal Communications Commission ordered telecommunication carriers of 83 area codes, including 970, to transition to ten-digit dialing, even when the area code is not involved in an overlay complex. Per the timeline set by the North American Numbering Plan Administrator, permissive dialing began on April 24, 2021 and ten-digit dialing has been required from October 24, 2021. [4]
In late 2025 or early 2026, area code 970 is expected to run out of available telephone numbers and an overlay is planned with a yet-to-be-determined new area code. [5]
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.
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 code 251 is a telephone area code in the North American Numbering Plan (NANP) for southwestern Alabama, serving Mobile, Baldwin, and Washington counties and parts of six other counties. It was created on June 18, 2001, as a split from area code 334. In order to allow people time to reprogram electronics such as computers, cell phones, pagers and fax machines, use of the 334 area code continued in the 251 areas through January 7, 2002.
Area codes 516 and 363 are telephone overlay area codes in the North American Numbering Plan (NANP) for the U.S. state of New York. The numbering plan area (NPA) comprises Nassau County on Long Island. Area code was created in 1951, and 363 was added to the numbering plan area in 2023.
Area code 804 is the telephone area code in the North American Numbering Plan (NANP) for the east-central portion of Virginia. The numbering plan area is anchored by Virginia's capital, Richmond, and includes most of its metropolitan area. Other communities included are Chesterfield, Henrico, Hopewell, Mechanicsville, Powhatan, Midlothian, Petersburg, and Colonial Heights. This also includes the Northern Neck and the Middle Peninsula. The two southernmost counties on the Middle Peninsula, Gloucester and Mathews, are part of the Hampton Roads metropolitan area, but use 804 instead of the area code 757 used by the rest of Hampton Roads.
Area codes 910 and 472 are telephone area codes in the North American Numbering Plan (NANP) for southeastern North Carolina. The area codes form an overlay for a numbering plan area (NPA) that includes the cities of Wilmington, Jacksonville, Laurinburg, Lumberton and Fayetteville. Area code 910 was established in 1993, and 472 was added to the same area in October 2022.
Area code 951 is a telephone area code in the North American Numbering Plan for western Riverside County in the southern part of the U.S. state of California. It was assigned in 2004 to a new numbering plan area that was created by an area code split of area code 909.
Area codes 707 and 369 are telephone area codes in the North American Numbering Plan (NANP) for the northwestern part of the U.S. state of California. The area codes serve part of the northern San Francisco Bay Area, as well as the North Coast. Major cities in the area codes include Napa, Sebastopol, Vallejo, Benicia, Fairfield, Santa Rosa, Windsor, Healdsburg, Rohnert Park, Petaluma, Fort Bragg, Rio Vista, Crescent City, Eureka, Clearlake, Vacaville, Dixon, and Ukiah. 707 was created by a split of area code 415 on March 1, 1959. Area code 369 was added to the numbering plan area (NPA) on February 1, 2023, to form an overlay numbering plan in the service area.
Area codes 845 and 329 are telephone area codes in the North American Numbering Plan (NANP) for the U.S. state of New York. The numbering plan area comprises the mid- and lower Hudson Valley, specifically Orange, Putnam, Rockland, and Ulster counties, and parts of Columbia, Delaware, Dutchess, Greene, and Sullivan counties.
Area code 603 is the sole area code for the U.S. state of New Hampshire in the North American Numbering Plan (NANP). It was created as one of the original 86 numbering plan areas in October 1947.
Area code 660 is the telephone area code in the North American Numbering Plan (NANP) for the northern and western part of the U.S. state of Missouri. It was created on October 12, 1997, in a split of the 816 numbering plan area (NPA)
Area code 319 is a telephone area code in the North American Numbering Plan (NANP) for the southeastern and east-central parts of the U.S. state of Iowa.
Area codes 513 and 283 are telephone area codes 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 code 719 is a telephone area code in the North American Numbering Plan (NANP) for the U.S. state of Colorado. The numbering plan area (NPA) includes Colorado Springs, Pueblo, Monument, Leadville, Alamosa, Monte Vista, the San Luis Valley, Cañon City, Trinidad, Rocky Ford, La Junta, Walsenburg and southeastern Colorado. It was created in a split of area code 303 on March 5, 1988. While 303 had been Colorado's sole area code for 40 years, the state's explosive growth in the second half of the 20th century made it apparent that the state would need another area code. 719 was split off when an impending number shortage meant the split could no longer be staved off.
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 912 is a telephone area code in the North American Numbering Plan (NANP) for the southeastern part of the U.S. state of Georgia. The numbering plan area contains Savannah, Richmond Hill, Hinesville, Vidalia, Metter, Reidsville, Homerville, Waycross, Brunswick, Folkston, Douglas, Statesboro, Ludowici, Jesup and Kingsland. The area code was created in 1954 in an area code split from area code 404, which had been assigned to the entire state in 1947.
Area codes 618 and 730 are telephone area codes in the North American Numbering Plan (NANP) for southern Illinois. The numbering plan area (NPA) comprises one hundred and twenty-six municipalities, such as Carbondale, Cairo, Belleville, East St. Louis, Edwardsville, Marion, O'Fallon, Alton, Mt. Vernon, Centralia, Herrin, Salem, Metropolis, Fairview Heights, Collinsville, and Granite City. Area code 618 was one of the original North American area codes created in 1947, and 730 was added to the plan area to form an overlay complex to satisfy the need for more telephone numbers in the region.
Area code 575 is a telephone area code in the North American Numbering Plan (NANP) for the U.S. state of New Mexico. The area code was created in 2007 in an area code split of area code 505, whose service area was reduced to the Albuquerque, Santa Fe, Farmington, and Gallup regions to provide more telephone numbers to the most populated parts of the state. Area code 575 serves the rest of the state.
| North: 307, 308 | ||
| West: 435 | 970 | East: 303/720, 719, 785 |
| South: 303/720, 505, 575, 719 | ||
| Kansas area codes: 316, 620, 785, 913 | ||
| Nebraska area codes: 308, 402/531 | ||
| New Mexico area codes: 505, 575 | ||
| Utah area codes: 385/801, 435 | ||
| Wyoming area codes: 307 | ||