Antioch, CA ZIP Codes & Directory
Antioch is located in Contra Costa County in California. Browse all active 5-digit USPS ZIP codes serving Antioch and surrounding Contra Costa County delivery districts.
All ZIP Codes in Antioch, CA
2 CodesAbout Antioch Mail Delivery & Postal Administration
ZIP codes in Antioch are administered by the United States Postal Service. Delivery routes are coordinated through regional Sectional Center Facilities (SCFs) servicing Contra Costa County and surrounding California metropolitan districts.
Frequently Asked Questions About Antioch, CA ZIP Codes
How many ZIP codes serve Antioch, California? ▾
Antioch, California is served by 2 active USPS postal delivery codes: 94509, 94531.
What county is Antioch located in? ▾
Antioch is an incorporated city located within Contra Costa County, California.
What is the population and demographic size of Antioch? ▾
According to official U.S. Census Bureau data, Antioch has an estimated population of 115,273 residents and is situated within the undefined.
How does mail sorting and delivery work in Antioch? ▾
Mail delivery in Antioch is operated by the United States Postal Service (USPS) through regional Sectional Center Facility (SCF) distribution plants servicing Contra Costa County and surrounding California counties.
How much does it cost to ship a package to Antioch, CA? ▾
Shipping costs to Antioch depend on the package weight, dimensions, shipping carrier (USPS, UPS, FedEx), and the distance from the origin ZIP code. To calculate exact postage rates, use our shipping cost estimator tool.
What is the standard delivery time for mail to Antioch? ▾
Standard USPS Ground Advantage typically takes 2-5 business days to reach Antioch, depending on the origin. Priority Mail generally arrives in 1-3 business days. Please check tracking for specific regional routing times.