ZIP Code 94503

94503 is one of California's ZIP codes, delivering to addresses in American Canyon, Napa County.

City: American Canyon
County: Napa County
State: California
Prefix: 945xx

Where this code sits

94503 is part of the 945xx range, the group of codes handled by one mail processing centre. It is the only ZIP code delivering to American Canyon.

American Canyon California ZIP codes →

Area codes over the same ground

Postal and telephone geography are drawn separately, so these codes cover the area 94503 delivers to without sharing its boundary.

ZIP codes nearest 94503

The ZIP codes whose reference points sit closest to 94503.
ZIP code	Distance	Delivers to
ZIP code 94589	1.5 mi	Vallejo, CA
ZIP code 94590	4.3 mi	Vallejo, CA
ZIP code 94592	4.9 mi	Vallejo, CA
ZIP code 94591	5.3 mi	Vallejo, CA
ZIP code 94525	8.2 mi	Crockett, CA
ZIP code 94510	8.5 mi	Benicia, CA
ZIP code 94534	8.5 mi	Fairfield, CA
ZIP code 94559	8.7 mi	Napa, CA

Straight-line distance between place reference points, not driving distance. Where a place has no Census Gazetteer point, its postal centroid is used instead.

Each point is the reference point for 94503, plotted from its record coordinates.

Reference points and footprint
Not an official NANPA boundary
Not a USPS delivery area

Scope ZIP code 94503. Source GeoNames US postal codes (2026-07 postal dump) and Census 2024 county Gazetteer (2024 Gazetteer). Updated 15 July 2026. A ZIP code is a set of delivery routes, not an area; the point shown is a record coordinate, not a centre.