Colorado ZIP Codes

ZIP codes: 645
Cities & towns: 399
Counties: 64
Area codes: 6

How Colorado ZIP codes are numbered

800xx–816xx

The first three digits identify the sectional center facility that processes mail for a region, so a Colorado ZIP code can be placed geographically from its prefix alone. Each row names the city holding the most codes in that prefix.

Colorado three-digit ZIP prefixes, the codes in each, and the city that holds the most of them.
Prefix	ZIP codes	Main area
800xx	40	Aurora
801xx	44	Littleton
802xx	67	Denver
803xx	11	Boulder
804xx	63	Golden
805xx	42	Fort Collins
806xx	32	Greeley
807xx	33	Akron
808xx	41	Limon
809xx	53	Colorado Springs
810xx	59	Pueblo
811xx	32	Alamosa
812xx	32	Canon City
813xx	17	Durango
814xx	26	Montrose
815xx	15	Grand Junction
816xx	38	Aspen

Where Colorado's communities sit

Each point is a Colorado community with a published ZIP code list, plotted from its record coordinates. The outline is the convex envelope of those points — a footprint, not a boundary.

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

Colorado cities by ZIP code count

largest 25

Area codes serving Colorado

Scope every ZIP code recorded in Colorado. Source GeoNames US postal codes (2026-07 postal dump) and Census 2024 county Gazetteer (2024 Gazetteer). Updated 15 July 2026. The map outline is a convex envelope of published places, not a state boundary.