Area code 510 Information & Area code 510 Links at HealthHaven.com

Map of California area codes in blue (and border states) with 510 in red

North American area code 510 is a California telephone area code which covers most eastern Bay Area cities in Alameda County (including the city of Oakland but excluding Dublin, Livermore, Pleasanton, and Sunol), and parts of Contra Costa County. The area code was created from a split of area code 415 on September 2, 1991.^[1] The area code is the origin of the urban slang "the nickel and dime", used by some to refer to the East Bay.^{[citation needed]}