Rock County ZIP Codes

Rock County is a county of Wisconsin.

ZIP codes: 15
Cities & towns: 11
Area codes: 3
Land area: 718 sq mi

Every ZIP code in Rock County

535xx

The complete list of Rock County, WI ZIP codes with the city each one delivers to.
ZIP code	City
53501	Afton
53505	Avalon
53511	Beloit
53512	Beloit
53525	Clinton
53534	Edgerton
53536	Evansville
53537	Footville
53542	Hanover
53545	Janesville
53546	Janesville
53547	Janesville
53548	Janesville
53563	Milton
53576	Orfordville

We do not publish a delivery type (standard, PO box, unique) or a neighbourhood for each ZIP.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

Cities and towns in Rock County

A further 3 places in Rock 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 Rock County

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

Where Rock County's ZIP codes sit

Each point is the reference point of one Rock 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 Rock 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.