Jefferson County, Wisconsin
10 ZIP codes · 556.49 sq mi of land · FIPS 55055
| Population | 86,003 |
|---|---|
| State | Wisconsin |
| FIPS code | 55055 |
| Time zone | Central |
| Land area | 556.49 sq mi |
| Center (lat, long) | 43.0138, -88.7740 |
Area codes in this area
These are the area codes that most often serve Jefferson County (including overlays). The exact area code depends on the phone number — landlines, mobiles and overlays can differ even on the same street.
Cities and towns (largest first)
Watertown · 22,774IxoniaJohnson CreekHelenvillePalmyraSullivanFort AtkinsonJeffersonLake MillsWaterloo
ZIP codes in Jefferson County
53036 Ixonia53038 Johnson Creek53094 Watertown53137 Helenville53156 Palmyra53178 Sullivan53538 Fort Atkinson53549 Jefferson53551 Lake Mills53594 Waterloo
Population: U.S. Census Bureau, ACS 5-year estimates, 2024.