County hub rural Wisconsin

Rock County, WI

Aggregated demographic, housing, and geographic context for the 13 ZIP codes inside Rock County, drawn from public Census ACS and SimpleMaps data.

ZIP codes
13
in this county
Total population
169,578
across all listed ZIPs
Cities
11
distinct city/town names
Avg density
123
people / sq mi
Avg median income
household, ACS
Avg home value
owner-occupied

ZIP codes in Rock County

ZIPCityPopulationDensityMedian income
53511 Beloit 48,714 164
53546 Janesville 29,505 141
53545 Janesville 23,571 404
53548 Janesville 20,314 105
53534 Edgerton 12,256 56
53563 Milton 11,716 68
53536 Evansville 8,936 39
53520 Brodhead 6,754 22
53525 Clinton 4,049 27
53576 Orfordville 2,291 28
53537 Footville 954 423
53505 Avalon 373 7
53501 Afton 145 123

About Rock County

Counties are the workhorse unit of American local government — they administer property taxes, run the courts and sheriff’s office, manage many road and library systems, and in much of the country they collect public health and zoning data that ZIP codes don’t. Rock County in Wisconsin contains roughly 13 ZIP codes spread across 11 distinct cities and unincorporated communities, with an aggregate population of about 169,578. Reading those ZIPs together at the county level smooths over neighborhood-by-neighborhood noise and surfaces the broader economic and demographic shape of the area. For block-level detail, drill into any individual ZIP profile or compare against the wider Wisconsin index.

The average density across listed ZIPs sits at roughly 123, which classifies the county overall as a rural environment. That label is a generalization — nearly every county contains both a relatively dense core and quieter outlying ZIPs, and the gap between them is often what determines where you actually want to live or open a business. Average median household income in our enriched ZIPs lands near —, with average owner-occupied home values around —; both numbers move dramatically as you cross from one ZIP to the next, so use the table above as a sorting tool, not a verdict.

If you’re moving into Rock County, the county itself is also where most of your real-life paperwork will land — vehicle registration, voter registration, property recording, and school district enrollment in many states. Knowing the county that contains your prospective ZIP makes it much easier to look up the right tax assessor, election office, or school district website. Our relocation guide walks through the order in which to tackle these handoffs after a move.

For service-area planning, the county is also where most US business licensing and many sales-tax rules are administered. Service businesses scoping Rock County should pair this aggregate view with the individual ZIP profiles to identify the densest, highest-income pockets first, then expand outward along whatever transportation corridor matches their delivery model.