Area code 520 is a telephone area code in the North American Numbering Plan (NANP) for the U.S. state of Arizona. The numbering plan area comprises Tucson and most of the southeastern part of the state.
Area code 520 was created in a split of area code 602 on March 19, 1995. Previously, 602 had been the sole area code for the entire state of Arizona since the introduction of area codes in 1947. Arizona's rapid growth in demand for telecommunication services during the second half of the 20th century, and the proliferation of mobile and data communication services in the 1990s required additional numbering resources. The numbering plan area originally comprised all of the state outside the Phoenix metropolitan area, but areas outside of southeastern Arizona were split again in 2001 to form area code 928 in 2001.
Area code 602 was the only area code for Arizona from the establishment of a nationwide telephone numbering plan in 1947. By the late 1980s, the state needed a second area code to satisfy population growth and increased demand for telephone numbers. Mountain Bell, the incumbent local exchange carrier in the state, requested a second area code for Arizona in 1988. [1] BellCore, which at the time administered the assignment of area codes, denied Mountain Bell's request and instead placed Arizona into the first phase of interchangeable dialing, in which central office codes with a middle digit of 0 or 1 were made available for use, in 1990. [2] This meant that in-state toll and collect calls would require dialing the area code. [3]
By the early 1990s, Arizona was one of the largest states served by only one area code, and it was apparent that the immediate need for a second area code could no longer be staved off. In advance of the 1995 introduction of interchangeable area codes (area codes with a middle digit not 0 or 1), and in response to continued population growth, Arizona was allocated a second area code, area code 520. The new area code completely surrounded metropolitan Phoenix, which mostly retained 602. [4] 520 was introduced on March 19, 1995. Permissive dialing of 602 continued across Arizona until October 22, 1995. On that date, use of 520 became mandatory for rural Arizona. The new area code became mandatory in Flagstaff, Prescott, and Yuma on June 30, 1996, and in Tucson on December 31, 1996. The freed central office codes in 602 were then used for new telephone numbers in the Phoenix area. [5]
Continued line demand in Arizona outside of metropolitan Phoenix, however, necessitated a second split of 520. In 2000, the Arizona Corporation Commission, which regulates public utilities, began to discuss its options. The telecommunications industry favored a split similar to that eventually adopted but moving Cochise County into the new area code. [6] The eventual split approved by the commission in February 2001 kept Cochise, Pima, Pinal, and Santa Cruz counties in 520 while the new area code, area code 928, was assigned to the remainder of the former 520 area. [7] (Some areas of Pinal County are in 480, while the Gila River Indian Community, which extends into Maricopa County, is in 520. [8] ) Permissive dialing of 928 began in July 2001 and ended January 5, 2002. [9]
Prior to October 2021, area code 520 had telephone numbers assigned for the central office code 988. In 2020, 988 was designated nationwide as a dialing code for the National Suicide Prevention Lifeline, which created a conflict for exchanges that permit seven-digit dialing. This area code was therefore scheduled to transition to ten-digit dialing by October 24, 2021. [10]
Area code 914 is the telephone area code in the North American Numbering Plan (NANP) for Westchester County, New York.
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 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 code 608 is a telephone area code in the North American Numbering Plan for much of southwestern Wisconsin, including the state capital city Madison. The area code was assigned in 1955 to a numbering plan area created from areas with area code 414 and area code 715, and was the third area code created in Wisconsin. Rapid growth of the area, specifically in Dane County, has brought the area code close to exhaustion of central office prefixes, with NANPA projections in 2022 projecting the need for relief by late 2023. In September 2022, the Wisconsin Public Service Commission and North American Numbering Plan Administrator (NANPA) announced an overlay complex for the numbering plan area with new area code 353, with an in-service date of September 15, 2023. New central office code orders were accepted starting on July 11, 2023, but can only be activated once all 608 central office codes are assigned.
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 the majority 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.
Area code 276 is a telephone area code in the North American Numbering Plan (NANP) for the western part of the U.S. state of Virginia. It was established by a split of area code 540 on September 1, 2001.
Area codes 602, 480, and 623 are telephone area codes in the North American Numbering Plan (NANP) for most of the Phoenix metropolitan area in the U.S. state of Arizona.
Area code 505 is a telephone area code in the North American Numbering Plan (NANP) for the U.S. state of New Mexico. Its numbering plan area (NPA) comprises the northwestern and central portions of the state, including the Albuquerque metropolitan area, Gallup, Santa Fe, and Farmington. The area code is one of the original North American area codes established in October 1947. Until October 7, 2007, it served the entire state.
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 an area code split of the 816 numbering plan area (NPA)
989 is the area code for Central Michigan, the northeastern Lower Peninsula, and portions of the Thumb. It is the highest-numbered area code in use in the North American Numbering Plan (NANP), as well as the highest possible under the current system, in which a middle digit of 9 is forbidden.
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 code 856 is a telephone area code in the North American Numbering Plan (NANP) for the southwestern part of the U.S. state of New Jersey. The numbering plan area (NPA) includes the Camden, Cherry Hill, and Vineland areas and a small part of Willingboro Township and the western part of Burlington County. 856 is essentially coextensive with the New Jersey side of the Philadelphia metropolitan area.
Area code 810 is one of the area codes in Michigan area code in the North American Numbering Plan (NANP) for East Central Michigan. The numbering plan area (NPA) comprises the cities of Flint, Lapeer, Port Huron, and the southern portion of the Thumb.
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 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 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.
Area code 515 is a telephone area code in the North American Numbering Plan (NANP) for most of the north-central part of the U.S. state of Iowa. The numbering plan area includes Des Moines, Ames, Ankeny, Humboldt, Boone, Fort Dodge, Jefferson, Johnston, Urbandale, Algona and Indianola.
Area code 731 is a telephone area code in the North American Numbering Plan (NANP) for the western part of the U.S. state of Tennessee.
North: 602/480/623, 928 | ||
West: 928 | 520 | East: 575 |
South: Country code 52 (Mexico) | ||
New Mexico area codes: 505, 575 |