ZIP Code 94531 – Antioch, CA
Antioch, California · Contra Costa County · Pacific time
| ZIP code | 94531 |
|---|---|
| City | Antioch |
| State | California |
| County | Contra Costa County |
| Population | 46,387 |
| Time zone | Pacific · local time |
| ZIP type | Standard (has a Census ZCTA area) |
| Land area | 14.03 sq mi |
| Center (lat, long) | 37.9566, -121.7778 |
Area codes in this area
These are the area codes that most often serve ZIP 94531 (including overlays). The exact area code depends on the phone number — landlines, mobiles and overlays can differ even on the same street.
Map
Nearby ZIP codes
About ZIP 94531
ZIP code 94531 is assigned to Antioch, California. It lies in Contra Costa County. Its Census area covers about 14.03 square miles of land. The closest neighboring ZIP is 94509 (Antioch), about 3.1 miles away.
Every address in 94531 also has a 4-digit add-on code (ZIP+4) that points to a smaller delivery area. Use the box above to find it.
Sources: US Census Bureau (ZCTA, county relationship files), GeoNames (CC BY 4.0), NANPA via NumberResearch.org (CC BY 4.0). Map © OpenStreetMap contributors. ZIP areas are approximate. Population: U.S. Census Bureau, ACS 5-year estimates, 2024 (ZCTA). Data sources