Area codes 415 and 628

Area code 415 is a California telephone area code that was one of the first three original area codes established in California in October 1947. It serves San Francisco and its northern suburbs in Marin County (across the Golden Gate Bridge), and the northeast corner of San Mateo County. It has been overlaid with area code 628 since February 21, 2015.

415 was one of the original three area codes in California, established in 1947. It originally covered central California, south of area code 916 and north of area code 213. It stretched from Sacramento in the north to Bakersfield in the south.

In 1950, 415 was extended along the North Coast to the Oregon border, while 916 was rotated to cover the northeastern corner of the state. As part of this realignment, Sacramento was shifted from 415 to 916, while Bakersfield moved to 213.

For a short time in the early 1950s, area code 318 was temporarily used, initially by customers in Englewood, New Jersey, participating in the first customer direct distance dialing experiment to reach San Francisco as well as some areas north of the Golden Gate. In 1953, the entire Bay Area was "reunited" in using area code 415.

Area 415 has been split three times due to the Bay Area's rapid growth:

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