Area codes 916 and 279

Area codes 916 and 279 are California telephone area codes that serve part of the Sacramento metropolitan area in Northern California. The largest city in this numbering plan area is Sacramento, the state capital. Area code 916 was one of the first three original area codes established in California in October 1947. It originally covered most of Northern California, but area code splits have reduced its coverage to the greater Sacramento area. Area code 279 began service in March 2018 to relieve an exhausted supply of telephone numbers in the 916 area code.

Originally, the plan area covered the far northern portion of the state. In 1950, as part of a realignment of California's area codes, 916 was rotated to cover the northeastern corner of California, from the Sierra Nevada to the Central Valley. This involved changing Sacramento from area code 415 to 916.

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