Thornton Colorado ZIP Codes

Thornton holds a single ZIP code.

We do not publish a delivery type (standard, PO box, unique) or a neighbourhood for each ZIP. USPS delivery-type products are licensed, and no clean-rights source maps ZIP codes to neighbourhoods — so the Thornton codes above are listed without a column we would have to invent.

Scope every ZIP code recorded for Thornton. Source GeoNames US postal codes (2026-07 postal dump) and Census 2024 county Gazetteer (2024 Gazetteer). Updated 15 July 2026. ZIP codes are delivery-route groupings, not areas; the boundaries implied by any ZIP map are approximations.

Every Thornton ZIP code begins 802. Those first three digits identify the sectional center facility that processes mail for this part of Colorado. Statewide that range covers 67 ZIP codes, so Thornton accounts for 1% of it.

Every Colorado ZIP prefix and the region it covers →

ZIP codes and area codes are separate systems — one routes mail, the other routes calls — and they do not share boundaries. The codes below serve the same ground Thornton occupies.

• 303 Area code 303
• 720 Area code 720
• 983 Area code 983

Thornton Colorado area codes in full →

Straight-line distance between place reference points, not driving distance.