Area codes 705, 249, and 683 are telephone area codes in the North American Numbering Plan (NANP) for most of northeastern and central Ontario in Canada. Area code 705 was created in a 1956 area code split from portions of the 613 and 519 numbering plan areas. After a reduction in geographic coverage in 1962, the numbering plan area was assigned a second area code, 249, in 2011 to form an overlay numbering plan. A third area code, 683, was added in June 2022.
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.
Area code 701 is a telephone area code in the North American Numbering Plan (NANP) for the U.S. State of North Dakota. It is one of the 86 original North American area codes created by AT&T in 1947, and continues to be the only area code in North Dakota, one of eleven states with only one area code.
Area code 781 and 339 are telephone area codes in the North American Numbering Plan for the U.S. state of Massachusetts. The numbering plan area consists of Boston’s inner suburbs along the Route 128 corridor, and some outer suburbs, especially in the South Shore region. Major cities and towns with the area code include Waltham, Woburn, Lynn, Weymouth and Dedham. It was created as in an area code split of area code 617 on September 1, 1997. Use of 781 became mandatory February 1, 1998. Area code 339 is an overlay complex code for the same service area, activated on May 2, 2001. Since then, ten-digit dialing has been mandatory.
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 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 604 is a telephone area code in the North American Numbering Plan for southwestern British Columbia, Canada. The numbering plan area comprises the Metro Vancouver, 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 codes 617 and 857 are telephone area codes in the North American Numbering Plan (NANP) for the U.S. state of Massachusetts, serving the city of Boston and several surrounding communities such as Brookline, Cambridge, Newton and Quincy. Area code 617 is one of the original North American area codes created in October 1947, when it served the eastern two-thirds of Massachusetts, from roughly the western end of Worcester County to Cape Cod and the South Coast.
Area code 605 is the telephone area code in the North American Numbering Plan for the entire U.S. state of South Dakota. The numbering plan area was designated in 1947, when the American Telephone and Telegraph Company (AT&T) devised a comprehensive telephone numbering plan for the United States and Canada.
Area code 406 is the telephone area code in the North American Numbering Plan for the entire U.S. state of Montana. It has been Montana's only area code since the American Telephone and Telegraph Company created a nationwide telephone numbering plan in 1947.