Jefferson County, Wisconsin
Jefferson County is a county in Wisconsin. Its county FIPS code is 55055. Use the boundary map and neighboring areas below to check the jurisdiction you need.
- Official code
- 55055
- Representative coordinates
- 43.013804, -88.773985
- County type
- County
- County seat or government
- Jefferson
- Resident population, July 2025
- 86,505
- Land area
- 1,441.312 km²
- Water area
- 67.982 km²
- State
- Wisconsin
The representative point identifies this area. It is not a street address or a boundary survey.
Time zones in Jefferson County
| Time zone | Local time and UTC offset | Next clock change |
|---|---|---|
| America/Chicago | UTC-06:00 in January; UTC-05:00 in July. Enable JavaScript for the live clock. | Enable JavaScript for upcoming changes. |
Listed zones overlap the mapped area. A point lookup can distinguish sides of a boundary. Your device’s zone may differ.
Census ZIP areas
53036 · 53038 · 53066 · 53094 · 53098 · 53118 · 53119 · 53137 · 53156 · 53178 · 53190 · 53523 · 53534 · 53538 · 53549 · 53551 · 53559 · 53563 · 53594
These statistical areas overlap the boundary. They are not delivery assignments; confirm mailing details with USPS ZIP Code Lookup.
Official county information
Jefferson County government website ↗ is the next stop for county offices, tax, voting, jury and records information. A geographic lookup cannot determine eligibility, tax liability or a court obligation.
Cities, towns and communities
These areas overlap the mapped boundary; an overlap does not mean that every address belongs to both.
- Cambridge village, WI
- Fort Atkinson city, WI
- Hebron CDP, WI
- Helenville CDP, WI
- Ixonia CDP, WI
- Jefferson city, WI
- Johnson Creek village, WI
- Lac La Belle village, WI
- Lake Koshkonong CDP, WI
- Lake Mills city, WI
- Lake Ripley CDP, WI
- Palmyra village, WI
- Rome CDP, WI
- Sullivan village, WI
- Waterloo city, WI
- Watertown city, WI
- Whitewater city, WI
Areas sharing the mapped boundary
These areas touch this mapped boundary.
Before using this answer on a form
Use a precise point for address-level questions. A device accuracy circle can cross a boundary; confirm tax, voting or jury details with the responsible office.
Find the county at your current point, check its ZIP area, or find its physical time zone.