List of North American Numbering Plan area codes

This is a list of North American telephone area codes in effect for the North American Numbering Plan (NANP). The area to which an area code is officially assigned is known as a Numbering Plan Area (NPA).
An area code is part of a telephone number in the United States, Canada, and the Caribbean. It is the part of the telephone number after the county code. For example, in the number 1-562-555-5555, the 1 is the country code (for the United States), and 562 is the area code. An area code is typically assigned to a state, city or region.
United States.
The following is a list of area codes in the United States, with some of the major cities that use that area code. Sometimes two or three codes are assigned to the same area. 
Canada.
The following is a list of area codes in Canada, with the major cities that use that area code. In Canada, some provinces share area codes. Sometimes two or three codes are assigned to the same area.