Area codes 587, 825, and 368 are telephone area codes in the North American Numbering Plan (NANP) for the entire Canadian province of Alberta. They form an overlay with area code 403 of southern Alberta, and northern Alberta's 780. The complex overlay involving a total of five area codes in Alberta mandated ten-digit dialing throughout the province.
Prior to 1997, numbering plan area 403 comprised Alberta, Yukon and the Northwest Territories, as well as a very small western portion of what is today Nunavut (which split off from the Northwest Territories on 1 April 1999). In 1997, use of area code 403 was restricted to Alberta, with the territories receiving new area code 867.
In January 1999, the province was divided into two numbering plan areas. The northern two thirds of Alberta, including Edmonton, received area code 780, while leaving 403 to serve Calgary and southern Alberta.
The projected exhaust dates for area codes 403 and 780 were March and October 2009, respectively. In 1997, two area codes, 587 and 825, were reserved by Bellcore for Alberta. [1]
The first of the new area codes, 587, entered service on September 19, 2008, as an overlay for the entire province. [2] [3] [4] As a preliminary step, ten-digit dialling was introduced across the province on an optional basis on June 23. This became mandatory on September 12. On September 20, Telus Mobility began allocating telephone numbers starting in area code 587 in the Calgary area. [5]
Instead of the overlay, splitting 403 or 780, would have resulted in subscribers in portions of Alberta having to change telephone numbers for the second time in a decade. A similar step had been taken a year earlier in British Columbia, when area code 778 was converted into an overlay complex for the entire province.
On April 9, 2016, the province was overlaid with an additional area code, 825. [6]
As of January 21, 2022, the province is additionally overlaid with area code 368. [7] [8]
Area code 568 is reserved as the sixth area code for the province since November 2022. [9]
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Area codes 905, 289, 365, and 742 are telephone area codes in the North American Numbering Plan (NANP) for the Golden Horseshoe region that surrounds Lake Ontario in Southern Ontario, Canada. The numbering plan area (NPA) comprises (clockwise) the Niagara Peninsula, the city of Hamilton, the regional municipalities of Halton, Peel, York, Durham, and parts of Northumberland County, but excludes the City of Toronto.
Area codes 519, 226, 548, and 382 are overlay telephone area codes in the North American Numbering Plan (NANP) for most of southwestern Ontario.
In telecommunications, an area code overlay complex is a telephone numbering plan that assigns multiple area codes to the same 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 exclusive method of area code 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 code 867 is the area code in the North American Numbering Plan (NANP) for the three Canadian territories, all of which are in Northern Canada. The area code was created on October 21, 1997, by combining regions that were previously served with area code 403 and area code 819 in one numbering plan area (NPA). As the least populated NPA in mainland North America, serving about 130,000 people, it is geographically the largest, at 3,921,739 km2 (1,514,192 sq mi), with Alaska (907) a distant second.
Area code 564 is a telephone overlay area code in the North American Numbering Plan (NANP) for Western Washington state, including metropolitan Seattle. The area code was first proposed in 1999 to relieve telephone number shortages in area code 360, but implementation was delayed until 2017, when it was installed for an overlay complex that comprises only the numbering plan area 360. Neighboring area codes 206, 253, and 425 were slated for expansion of the overlay upon exhaustion of central office codes in each NPA. In 2023, area code 206 was approved for expansion with a guide line for preparation of inclusion of at least nine months. Ten-digit dialing has been mandatory in all of western Washington since July 29, 2017.
Telephone number pooling, thousands-block number pooling, or just number pooling, is a method of allocating telephony numbering space of the North American Numbering Plan in the United States. The method allocates telephone numbers in blocks of 1,000 consecutive numbers of a given central office code to telephony service providers. In the United States it replaced the practice of allocating all 10,000 numbers of a central office prefix at a time. Under number pooling, the entire prefix is assigned to a rate center, to be shared among all providers delivering services in that rate center. Number pooling reduced the quantity of unused telephone numbers in markets which have been fragmented between multiple service providers, avoided central office prefix exhaustion in high growth areas, and extended the lifetime of the North American telephone numbering plan without structure changes of telephone numbers. Telephone number pooling was first tested for area code 847 in Illinois in June 1998, and became national policy in a series of Federal Communications Commission (FCC) orders from 2000 to 2003.
Area codes 514, 438, and 263 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 204, 431, and 584 are telephone area codes in the North American Numbering Plan (NANP) for the Canadian province of Manitoba. Area code 204 is one of the nine original North American area codes assigned to Canada in 1947. Area codes 431 and 584 were assigned to the same numbering plan area (NPA) in 2012 and 2022, respectively, forming an overlay complex.
Area codes 778, 236, and 672 are telephone area codes in the North American Numbering Plan (NANP) for the Canadian province of British Columbia. They form an overlay complex with area code 604, which serves only a small southwestern section, the Lower Mainland, of the province, and area code 250, which serves the rest of the province.
Area codes 306, 639, and 474 are telephone area codes in the North American Numbering Plan (NANP) for the entire Canadian province of Saskatchewan. Area code 306 is one of the original North American area codes assigned in 1947. Area codes 639 and 474 were added to the numbering plan area in creation of an overlay complex for the entire province in 2013 and 2021, respectively. The incumbent local exchange carrier is SaskTel.
Area code 403 is a telephone area code in the North American Numbering Plan (NANP) for the Canadian province of Alberta. The numbering plan area encompasses the southern third of the province, which includes the Calgary area. This numbering plan area is also served by area codes 587, 825, and 368, which form a complex overlay for all of Alberta.
Area code 780 is a telephone area code in the North American Numbering Plan (NANP) for the Canadian province of Alberta. The numbering plan area comprises the northern two thirds of the province, including the Edmonton area. The area code was established in 1999 in a split of area code 403, which had served the entire province since the establishment of the original North American area codes in 1947. The numbering plan area is also served by area codes 587, 825, and 368, which form a complex overlay for all of Alberta.
Area code 807 is a telephone area code in the North American Numbering Plan (NANP) for the Canadian province of Ontario. The numbering plan area (NPA), comprising only Northwestern Ontario, was created in early 1962 in an area code split of NPA 705. The main reason for the split was not central office prefix exhaustion, but routing efficiency for calls from Western Canada to northwestern Ontario.
Area codes 506 and 428 are the telephone area codes in the North American Numbering Plan (NANP) for the Canadian province of New Brunswick. Area code 506 was created in 1955 in a split of numbering plan area (NPA) 902. Area code 428 was added to the same numbering plan area in 2023 to form an overlay plan of the area.
Area code 709 is the telephone area code in the North American Numbering Plan (NANP) for the entire Canadian province of Newfoundland and Labrador.
Area code 604 is a telephone area code in the North American Numbering Plan for southwestern British Columbia, Canada. The numbering plan area comprises the Lower Mainland, Sunshine Coast, Howe Sound / Sea to Sky Corridor, Fraser Valley and the lower Fraser Canyon regions. The major city is Vancouver. The area code is one of the nine original North American area codes assigned to Canada in 1947.
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. On August 17, 2001, the numbering plan area was converted to an overlay complex with area code 878, which also forms an overlay with area code 724, in the surroundings of the 412 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.
| North: 867 | ||
| West: 250/778/236/672 | 368/587/825, 403, 780 | East: 306/639 |
| South: 406 | ||
| British Columbia area codes: 236/672/778, 250, 604 | ||
| Saskatchewan area codes: 306, 639 | ||
| Montana area codes: 406 | ||
| Yukon, Northwest Territories and Nunavut area codes: 867 | ||