Contra Costa County, California
Contra Costa County is a county in California. Its county FIPS code is 06013. Use the boundary map and neighboring areas below to check the jurisdiction you need.
- Official code
- 06013
- Representative coordinates
- 37.919479, -121.951543
- County type
- County
- County seat or government
- Martinez
- Resident population, July 2025
- 1,170,070
- Land area
- 1,856.765 km²
- Water area
- 225.326 km²
- State
- California
The representative point identifies this area. It is not a street address or a boundary survey.
Time zones in Contra Costa County
| Time zone | Local time and UTC offset | Next clock change |
|---|---|---|
| America/Los_Angeles | UTC-08:00 in January; UTC-07:00 in July. Enable JavaScript for the live clock. | Enable JavaScript for upcoming changes. |
Listed zones overlap the mapped area. A point lookup can distinguish sides of a boundary. Your device’s zone may differ.
Census ZIP areas
94505 · 94506 · 94507 · 94509 · 94511 · 94513 · 94514 · 94516 · 94517 · 94518 · 94519 · 94520 · 94521 · 94523 · 94525 · 94526 · 94528 · 94530 · 94531 · 94547 · 94548 · 94549 · 94551 · 94553 · 94556 · 94561 · 94563 · 94564 · 94565 · 94569 · 94572 · 94575 · 94582 · 94583 · 94588 · 94595 · 94596 · 94597 · 94598 · 94611 · 94706 · 94707 · 94708 · 94801 · 94803 · 94804 · 94805 · 94806 · 95219
These statistical areas overlap the boundary. They are not delivery assignments; confirm mailing details with USPS ZIP Code Lookup.
Official county information
Use the US government local-office directory ↗ to find the office responsible for your address. A county website has not been confidently matched here. A geographic lookup cannot determine eligibility, tax liability or a court obligation.
Cities, towns and communities
These areas overlap the mapped boundary; an overlap does not mean that every address belongs to both.
- Acalanes Ridge CDP, CA
- Alamo CDP, CA
- Alhambra Valley CDP, CA
- Antioch city, CA
- Bay Point CDP, CA
- Bayview CDP, CA
- Bethel Island CDP, CA
- Blackhawk CDP, CA
- Brentwood city, CA
- Byron CDP, CA
- Camino Tassajara CDP, CA
- Castle Hill CDP, CA
- Clayton city, CA
- Clyde CDP, CA
- Concord city, CA
- Contra Costa Centre CDP, CA
- Crockett CDP, CA
- Danville town, CA
- Diablo CDP, CA
- Discovery Bay CDP, CA
- East Richmond Heights CDP, CA
- El Cerrito city, CA
- El Sobrante CDP, CA
- Hercules city, CA
- Kensington CDP, CA
- Knightsen CDP, CA
- Lafayette city, CA
- Martinez city, CA
- Montalvin Manor CDP, CA
- Moraga town, CA
Browse all cities, towns and communities for Contra Costa County
Areas sharing the mapped boundary
These areas touch this mapped boundary.
Before using this answer on a form
Use a precise point for address-level questions. A device accuracy circle can cross a boundary; confirm tax, voting or jury details with the responsible office.
Find the county at your current point, check its ZIP area, or find its physical time zone.
Small boundary contacts to check
These maps have small contacts that do not confidently establish another jurisdiction or clock zone. They remain separate from the main answer. Check a precise address near the line with the responsible authority.