Area codes 305, 786, and 645

Area codes 305, 786, and 645 are telephone area codes in the North American Numbering Plan (NANP) for Miami, Florida, Miami-Dade County, and the part of Monroe County in the Florida Keys in the United States.

In 1947, the American Telephone and Telegraph Company (AT&T) announced the first nationwide telephone numbering plan and divided the United States and Canada into 86 numbering plan areas and assigned the original North American area codes, a unique code for each area, to speed the connection times for operator toll dialing.

[1] As a result of the increase in the state's population,[citation needed] North Florida from the Panhandle to Jacksonville was assigned area code 904 with a permissive dialing period beginning July 6, 1965, and mandatory dialing beginning January 1, 1966.

[5] Within two years, the reconfigured area code 305 was close to exhaustion due to growth in Dade County from the increasing popularity of cell phones and pagers.

[10][11] The Florida Public Service Commission approved a third area code for the Miami region on February 25, 2022.