Where Is Area Code 510?
Area code 510 serves California’s East Bay, including Alameda and nearby communities on the eastern side of San Francisco Bay. The area covers much of western and southern Alameda County and extends into western Contra Costa County. Alameda is the primary city, while Oakland, Berkeley, Fremont, Hayward, Richmond, and San Leandro are other major cities in the area.
The region includes Albany, Castro Valley, El Cerrito, Emeryville, Newark, Piedmont, Pinole, San Pablo, and Union City. Notable geographic features include San Francisco Bay, Alameda Island, and the East Bay Hills. Major landmarks include the University of California, Berkeley, the Port of Oakland, Oakland International Airport, and the Oakland side of the San Francisco-Oakland Bay Bridge.
Cities and Communities in the 510 Area Code
- Alameda, Alameda County
- Albany, Alameda County
- Berkeley, Alameda County
- Castro Valley, Alameda County
- Crockett, Contra Costa County
- El Cerrito, Contra Costa County
- El Sobrante, Contra Costa County
- Emeryville, Alameda County
- Fremont, Alameda County
- Hayward, Alameda County
- Hercules, Contra Costa County
- Kensington, Contra Costa County
- Newark, Alameda County
- Oakland, Alameda County
- Piedmont, Alameda County
- Pinole, Contra Costa County
- Richmond, Contra Costa County
- Rodeo, Contra Costa County
- San Leandro, Alameda County
- San Lorenzo, Alameda County
- San Pablo, Contra Costa County
- Union City, Alameda County
History of Area Code 510
Area code 510 was established on March 2, 1991, when it split from area code 415. The change created a separate East Bay numbering area, while area code 415 continued to serve San Francisco and nearby areas.
Area code 925 split from area code 510 on March 14, 1998, taking eastern portions of Alameda and Contra Costa counties. Area code 341 became an overlay for area code 510 on July 22, 2019, and the two codes now serve the same geographic region. These changes followed increased demand for telephone numbers from households, businesses, schools, and public services in the growing East Bay.
Key Facts About Area Code 510
- Area code 510 is a California area code in the U.S. Census Pacific region.
- Alameda is the primary city associated with area code 510.
- Area code 510 is a geographic area code, not a toll-free code.
- Area code 510 uses Pacific Time.
- Area code 510 serves parts of Alameda and Contra Costa counties.
- Area code 510 originated in a split from area code 415 on March 2, 1991.
- Area code 341 has overlaid area code 510 since July 22, 2019.
- The 510 service area includes the University of California, Berkeley, the Port of Oakland, and Oakland International Airport.
Frequently Asked Questions
What state is area code 510 in?
Area code 510 is in California.
What major cities use area code 510?
Major cities include Alameda, Oakland, Berkeley, Fremont, Hayward, Richmond, and San Leandro.
What time zone is area code 510 in?
Area code 510 is in Pacific Time.
Is area code 510 a toll-free number?
No, area code 510 is a geographic area code, not a toll-free number.