Rock County, Wisconsin
Located in Wisconsin, Rock County has a population of 164,350 residents and a median age of 40.3 years, making it the #420 most populous county out of 3,222 nationwide. In terms of economic indicators, the county has a poverty rate of 9.3%. The median home value is $231,600, and the median household income is $75,673, which is 1% above the national median.
Demographics
Rock County has a population of 164,350, making it the #420 most populous county in the US. The median age is 40.3 years, which is 3.6% above the national median.
Population Trend
Rankings →Year-over-Year Population Growth
Age & Sex Distribution
Race & Ethnicity
Nativity
Geographic Mobility (Past Year)
Economy
The median household income in Rock County is $75,673, ranking #797 out of 3,222 counties — 0.7% above the national median. The poverty rate is 9.3% and unemployment stands at 3.8%.
Median Household Income Trend
Rankings →Income Distribution
Industry of Employment
Occupation
Housing
The median home value in Rock County is $231,600 (-17.8% vs national). Renters pay a median of $1,037/mo and the homeownership rate is 71.2%.
Median Home Value Trend
Rankings →Household Type
Education
In Rock County, 25.8% of adults age 25+ hold a bachelor's degree or higher, which is 23.4% below the national average, ranking #1,137 out of 3,222 counties.
Bachelor's Degree or Higher Trend
Rankings →Health & Wellbeing
Life expectancy in Rock County is 76.3 years. 15.8% of adults report poor or fair health and 6.6% lack health insurance. Data from County Health Rankings (2025).
Life Expectancy Trend
Substance Use
17.8% of adults in Rock County smoke , 38.1% are obese , and 22.4% report excessive drinking. The drug overdose death rate is 42.9 per 100,000.
Adult Smoking Trend
Safety
The homicide rate in Rock County is 3.5 per 100,000 and the suicide rate is 17.1 per 100,000. Motor vehicle deaths occur at a rate of 14.3 per 100,000.
Homicide Rate Trend
Families & Children
14.9% of children in Rock County live in poverty and the infant mortality rate is 5.7 per 1,000 live births. The teen birth rate is 18.1 per 1,000 females age 15–19.
Infant Mortality Trend
Civic & Transportation
Voter turnout in Rock County is 70.5%. The mean commute time is 25.9 min, which is 6.0% below the national average.
Voter Turnout Trend
Mean Commute Time Trend
Rankings →Elections
In the 2024 presidential election, Rock County voted Democratic with a margin of 7.3%. The vote was 52.9% Dem / 45.6% Rep. Compared to 2020, the margin shifted 3.9 toward Republicans .
Vote Share Over Time
About Rock County, Wisconsin
Rock County, Wisconsin has a total population of 164,350, making it the 420th most populous county in the United States. The median age in Rock County is 40.3 years, which is 3.6% above the national median of 38.9 years.
The median household income in Rock County is $75,673, which ranks #797 of 3,222 counties nationwide. This is 0.7% above the national median of $75,149. The poverty rate is 9.3%, lower than the national rate of 12.6%. The unemployment rate stands at 3.8%.
The median home value in Rock County is $231,600, 17.8% below the national median. Renters in Rock County pay a median gross rent of $1,037 per month. The homeownership rate is 71.2%, compared to the national rate of 64.4%.
In Rock County, 25.8% of residents aged 25 and older hold a bachelor's degree or higher, 23.4% below the national average of 33.7%. Health insurance coverage stands at 94.5% of the population. The average commute time for workers is 25.9 min.
Rock County is a diverse community. The largest racial or ethnic group is White (non-Hispanic) at 79.6% of the population, followed by Hispanic or Latino (10.1%) and Black (non-Hispanic) (4.6%).
All data for Rock County, Wisconsin comes from the U.S. Census Bureau's American Community Survey (ACS) 5-Year Estimates. These figures are estimates based on survey sampling and are subject to margin of error. For the most detailed and up-to-date data, visit the Census Bureau's official data portal.