Jefferson County, Iowa
Located in Iowa, Jefferson County has a population of 15,705 residents and a median age of 43.7 years, making it the #2,116 most populous county out of 3,222 nationwide. In terms of economic indicators, the county has a poverty rate of 15.2%. The median home value is $163,400, and the median household income is $61,620, which is 18% below the national median.
Demographics
Jefferson County has a population of 15,705, making it the #2,116 most populous county in the US. The median age is 43.7 years, which is 12.3% 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 Jefferson County is $61,620, ranking #1,925 out of 3,222 counties — 18.0% below the national median. The poverty rate is 15.2% and unemployment stands at 8.0%.
Median Household Income Trend
Rankings →Income Distribution
Industry of Employment
Occupation
Housing
The median home value in Jefferson County is $163,400 (-42.0% vs national). Renters pay a median of $883/mo and the homeownership rate is 67.7%.
Median Home Value Trend
Rankings →Household Type
Education
In Jefferson County, 43.2% of adults age 25+ hold a bachelor's degree or higher, which is 28.3% above the national average, ranking #194 out of 3,222 counties.
Bachelor's Degree or Higher Trend
Rankings →Health & Wellbeing
Life expectancy in Jefferson County is 77.1 years. 17.0% of adults report poor or fair health and 7.8% lack health insurance. Data from County Health Rankings (2025).
Life Expectancy Trend
Substance Use
17.2% of adults in Jefferson County smoke , 37.4% are obese , and 21.6% report excessive drinking. The drug overdose death rate is 24.1 per 100,000.
Adult Smoking Trend
Safety
The suicide rate is 20.9 per 100,000. Motor vehicle deaths occur at a rate of 10.6 per 100,000.
Suicide Rate Trend
Families & Children
18.6% of children in Jefferson County live in poverty . The teen birth rate is 15.7 per 1,000 females age 15–19.
Teen Birth Rate Trend
Civic & Transportation
Voter turnout in Jefferson County is 69.0%. The mean commute time is 18.0 min, which is 34.6% below the national average.
Voter Turnout Trend
Mean Commute Time Trend
Rankings →Elections
In the 2024 presidential election, Jefferson County voted Republican with a margin of 6.8%. The vote was 45.5% Dem / 52.3% Rep. Compared to 2020, the margin shifted 5.4 toward Republicans .
Vote Share Over Time
About Jefferson County, Iowa
Jefferson County, Iowa has a total population of 15,705, making it the 2,116th most populous county in the United States. The median age in Jefferson County is 43.7 years, which is 12.3% above the national median of 38.9 years.
The median household income in Jefferson County is $61,620, which ranks #1,925 of 3,222 counties nationwide. This is 18.0% below the national median of $75,149. The poverty rate is 15.2%, higher than the national rate of 12.6%. The unemployment rate stands at 8.0%.
The median home value in Jefferson County is $163,400, 42.0% below the national median. Renters in Jefferson County pay a median gross rent of $883 per month. The homeownership rate is 67.7%, compared to the national rate of 64.4%.
In Jefferson County, 43.2% of residents aged 25 and older hold a bachelor's degree or higher, 28.3% above the national average of 33.7%. Health insurance coverage stands at 93.3% of the population. The average commute time for workers is 18.0 min.
Jefferson County is a diverse community. The largest racial or ethnic group is White (non-Hispanic) at 82.4% of the population, followed by Asian (non-Hispanic) (8.2%) and Hispanic or Latino (4.1%).
All data for Jefferson County, Iowa 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.