Area code 510

Area code 510 is a telephone area code in the state of California. It was created on 1991, as a split from area code 415. It primarily serves the western part of Alameda County, including cities such as Oakland, Berkeley, Hayward, and part of Fremont, as well as parts of Contra Costa County. It was split by 925 in 1998 and then overlaid by 341 in 2019.