510 Area Code Background 

The 510 area code was created when it was split off of the 415 area code in September 1991.The 510 area code was split again when the 925 area code was split off in 1998.

The area served by the 510 area code includes the western portions of Alameda and Contra Costa Counties. The 510 area code serves the following cities:

Alameda County	Contra Costa County
Alameda	El Cerrito
Albany	Hercules
Berkeley	Pinole
Emeryville	Richmond
Fremont	San Pablo
Hayward
Newark
Oakland
Piedmont
San Leandro
Union City

 

This area code has a mix of urban and suburban cities with heavy industrial areas, oil refineries, chemical plants, as well as metropolitan, commercial and residential areas with varied growth. Also included are the former Alameda Naval Air Station development, Oakland International Airport, major bay area shipping ports, several universities and colleges, hospitals, museums and three major league sports teams. The 510 area code is bordered on the north by the 707 area code, directly to the west by the San Francisco Bay and then further west by the 415/628 area code overlay complex and the 650 area code; to the east by the 925 area code and to the south by the 408/669 area code overlay complex.