Area codes 415 and 628

Area codes 415 and 628 are telephone area codes in the North American Numbering Plan. They cover San Francisco and the surrounding areas in California, including Marin County and part of San Mateo County. Area code 415 was one of the original area codes established in 1947. Area code 415 originally covered a much larger region but was split multiple times to create new area codes, such as 408 and 707 in 1959,^[1] 510 in 1991,^[2] and 650 in 1997, due to the increasing demand for phone numbers. It was overlaid by 628 in 2015.

References

1. "NANP Area Code History: 1948 - 1959". Archived from the original on 2002-09-11. Retrieved 2024-07-08.
2. "Bellcore Letter" (PDF). Archived from the original on 2011-06-04. Retrieved 2024-07-08.