Every ZIP code in Lyon County

512xx

The complete list of Lyon County, IA ZIP codes with the city each one delivers to.
ZIP code	City
51230	Alvord
51235	Doon
51237	George
51240	Inwood
51241	Larchwood
51242	Lester
51243	Little Rock
51246	Rock Rapids

We do not publish a delivery type (standard, PO box, unique) or a neighbourhood for each ZIP.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

Cities and towns in Lyon County

Area codes covering Lyon County

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

Where Lyon County's ZIP codes sit

Each point is the reference point of one Lyon 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 Lyon 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.