Fremont County ZIP Codes

Fremont County is a county of Idaho.

ZIP codes: 8
Cities & towns: 8
Area codes: 2
Land area: 1,864 sq mi

Every ZIP code in Fremont County

834xx

The complete list of Fremont County, ID ZIP codes with the city each one delivers to.
ZIP code	City
83420	Ashton
83421	Chester
83429	Island Park
83433	Macks Inn
83436	Newdale
83438	Parker
83445	Saint Anthony
83451	Teton

We do not publish a delivery type (standard, PO box, unique) or a neighbourhood for each ZIP.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 Fremont County codes above are listed without a column we would have to invent.

Cities and towns in Fremont County

A further 3 places in Fremont County appear in the postal source without a page of its own; their codes are in the table above and each one links to its own page.

Area codes covering Fremont County

Telephone and postal boundaries are drawn by different bodies, so these codes overlap the county without matching its edges.

Where Fremont County's ZIP codes sit

Each point is the reference point of one Fremont County ZIP code, 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

Scope every ZIP code recorded in Fremont County. Source GeoNames US postal codes (2026-07 postal dump), Census 2024 county Gazetteer (2024 Gazetteer) and geoinfo-dataset (full_dataset) ZIP→NPA (2018 snapshot). Updated 16 July 2026. The outline is a convex envelope of ZIP reference points, not a jurisdiction boundary.