ZIP code · Antioch · California · United States

ZIP code 94509 — Antioch

ZIP code 94509 serves Antioch, California.

Postal code
94509
Single source Value from one source, not cross-checked.
City
Antioch
County
Contra Costa FIPS 06013
State
California
Country
United States
Coordinates
37.9939, -121.8089 — precision precise (locality)
View on OpenStreetMap
Population
71,013 (ZCTA, ACS 5-year)
Population density
4,071 / sq mi
Land area
17.4 sq mi (45.2 km²) (ZCTA, ACS 5-year)
Median household income
$81,512
Per-capita income
$36,589
Median age
37.6
Households
23,431
Housing units
24,048
Median home value
$565,300
Median gross rent
$2,052 / month
Congressional districts
CA-8 (also CA-10) (119th Congress)
USDA hardiness zone
9b (25 to 30 °F)
Planting / growing zone from the 2023 USDA Plant Hardiness Zone Map: average annual extreme minimum temperature, 1991–2020.
Time zone
America/Los_Angeles (UTC−8 / UTC−7 DST)
Area code
925
Telephone area codes serving this ZIP (NANPA central-office assignments). A ZIP and an area code are different boundaries; at a border both codes may apply.

Climate — monthly normals

Warmest month Jul (avg high 91°F), coldest Jan (avg low 40°F).

JanFebMarAprMayJunJulAugSepOctNovDec
Avg high °F566167727986919087786556
Avg low °F404447505459616059544640
Precip in2.72.41.90.90.40.10.00.00.10.41.22.5

NOAA 1991–2020 climate normals from the nearest station: ANTIOCH PUMPING PLT #3 (3.2 mi) · NOAA NCEI

Places in ZIP 94509

Places mapped inside this ZIP’s ZCTA area in OpenStreetMap. OSM is community-maintained: counts reflect what has been mapped, and completeness varies by area — treat them as at-least figures. © OpenStreetMap contributors (ODbL) · Methodology

About this page

US ZIP codes have five digits. They are postal routing areas, not administrative boundaries: a ZIP can span more than one city or county, and the city shown is the primary USPS name for that code.

GeoNames · U.S. Census Bureau (ACS) · U.S. Census Bureau · NOAA NCEI · usda-phzm. Data generated on 2026-08-21. Methodology · Report an error on this page