Janesville, WI ZIP Codes
Janesville, Wisconsin has 4 ZIP codes: 3 for street addresses (, and ) and 1 for PO boxes ().
Your street decides which one you use.
Which Janesville ZIP code is my address in?
Street ranges from the Census Bureau, 2026. PO box and organization ZIP codes are not found by street. A new street may be missing: address not found?
Janesville ZIP code map
Tap or point to an area to see its ZIP code.Full-size map
53547 has no area on the map: it is a PO box or single-organization ZIP code. Dashed line: Janesville city limits.
Map: Census Bureau ZIP Code Tabulation Areas (2020) and place limits (2024).
All Janesville ZIP codes by type
| ZIP | Type and post office or station |
|---|---|
| 53545 | street delivery Janesville |
| 53546 | street delivery Janesville |
| 53547 | PO boxes at the Janesville post office Janesville |
| 53548 | street delivery Janesville |
ZIP codes from nearby towns that reach into Janesville
- 53563, mailing town Milton, covers 4 percent of Janesville
Why your mail may say Janesville when you live outside it
Janesville ZIP codes also cover La Prairie, Rock and Center, so a letter addressed to Janesville can go to a home outside the city limits.
The reverse happens too: parts of Janesville use 53563, which mails under a neighboring town's name.
A ZIP code does not set your city, school district or tax. Rock County property records show which city you are in.
Janesville ZIP code questions
What is the main ZIP code for Janesville?
53545, the ZIP code of the main Janesville post office at 1818 Milton Ave.
Which Janesville ZIP codes are for PO boxes only?
53547. Mail to it goes to boxes at the post office, not to street addresses.
What county is Janesville in?
Rock County.
ZIP codes for towns near Janesville
More towns near Janesville: Crystal Lake, New Berlin, Algonquin, Brookfield, Franklin, Carpentersville, DeKalb, Greenfield, West Allis.
Sources and last checked
USPS ZIP Locale Detail (October 1, 2026), GeoNames (CC BY 4.0), U.S. Census Bureau, HUD-USPS crosswalk.
Checked October 20, 2026. Sources · How we build our lists · Corrections