Area code 707

Area code 707 is a telephone area code in the North American Numbering Plan for the northwestern part of the U.S. state of California. It was created by a split of area code 415 on March 1, 1959. It serves part of the northern San Francisco Bay Area, as well as the North Coast. Major cities in the area code include Napa, Sebastopol, Vallejo, Benicia, Fairfield, Santa Rosa, Windsor, Healdsburg, Rohnert Park, Petaluma, Fort Bragg, Crescent City, Eureka, Clearlake, Vacaville, and Ukiah.

When the North American Numbering Plan was created by AT&T in 1947, the far northern part of California received area code 916, with the exclusion of the city of Sacramento, which used area code 415. California area codes were reorganized geographically in 1950, so that 916 was assigned to a numbering plan area that comprised only the northeastern part from the Sierra Nevada to the Central Valley. The coastal area to the west was assigned area code 415. With this change, Sacramento was also changed to area code 916.

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