When the American Telephone and Telegraph Company (AT&T) created the first nationwide telephone numbering plan for Operator Toll Dialing in 1947 to automate and speed the connection of long-distance calls, the United States and Canada were divided into 86 geographic numbering plan areas (NPAs) and assigned the original North American area codes.
Due to the proliferation of cell phones and pagers in the 1990s, the Twin Cities were running out of central office codes for expansion of the numbering plan.
To mitigate continuing exhaustion, the Minneapolis Public Utilities Commission approved a three-way area code split of the remainder of NPA 612, for which the North American Numbering Plan Administration (NANPA) assigned new area codes 763 and 952 on November 29, 1999.
[1] The area code split took effect on February 27, 2000, and placed the following communities, all suburbs to the north and northwest of Minneapolis, into the 763 numbering plan area, including Brooklyn Center, Fridley, Mounds View, Blaine, Coon Rapids, Circle Pines, Lexington, St. Francis, Isanti, Cambridge, Princeton, Elk River, Becker, Monticello, Buffalo, Waverly, Delano, Medina, Plymouth and Golden Valley.
[1] Despite the three-way split of NPA 612, most of the Twin Cities remained a single rate center shared between all area codes.