Contra Costa County Area Codes

About Contra Costa County Area Codes

The county of Contra Costa County, located in California, is served by 2 telephone area code(s) in this dataset. These calling codes cover cities, suburbs, and unincorporated communities across the county.

Major phone area codes used in Contra Costa County include 510, 925. The county mainly follows the America/Los_Angeles time zone.

Cities and towns served by these area codes in Contra Costa County include Antioch, Bay Point, Brentwood, Concord, Danville, El Cerrito, Lafayette, Martinez, Oakley, Pittsburg, Pleasant Hill, Richmond, San Pablo, San Ramon, Walnut Creek.

List of Area Codes in Contra Costa County, California

The table below lists all telephone area codes used in Contra Costa County, California, along with their associated cities and time zones from this dataset.

Related Area Code Pages

Explore related area code resources on Burning Compass:

• All area codes in California
• Individual area code details are available from the table above.