Area codes 416, 647, and 437 are telephone area codes in the North American Numbering Plan (NANP) for the city of Toronto, Ontario, Canada. Area code 416 is one of the original North American area codes created by the American Telephone and Telegraph Company (AT&T) in 1947. Area codes 647 and 437 are additional area codes for the same numbering plan area (NPA), forming an overlay numbering plan.

The original North American area codes were established by the American Telephone and Telegraph Company (AT&T) in 1947, after the demonstration of regional Operator Toll Dialing during the World War II period. The program had the goal of speeding the connecting times for long-distance calling by eliminating intermediary telephone operators. Expanding this technology for national use required a comprehensive and universal, continent-wide telephone numbering plan.