| Name | Jefferson County |
| State | Wisconsin |
| FIPS Code | 55055 |
| County Seat | Jefferson |
| Timezone | Central Standard Time (CST) |
| Population (2022) | 83,751 |
| Population Growth Rate(2000-2022) | 1.45% |
| Majority Ethnicity | White 97.84% |
| Public School Majority Ethnicity | White 76% |
| Partisan Voting Index | Republican:+6 |
| Unemployment Rate (December 2024) | 2.2% |
| Area Code(s) | 274 / 920 / 262 / 608 |
| Race/Ethnicity | Percentage of Population (2022) |
|---|---|
| White | 97.84% |
| African American | 1.24% |
| Hispanic | 0.32% |
| Asian | 0.54% |
| Native American | 0.03% |
| Hawaiin/Pacific Islander | 0.03% |
| Race/Ethnicity | Percentage of Public School Students (2023) |
|---|---|
| White | 76% |
| African American | 1.49% |
| Hispanic | 17.82% |
| Asian | 1% |
| Native American | 0.15% |
| Hawaiin/Pacific Islander | 0.07% |