Marshall County, Iowa
Located in Iowa, Marshall County has a population of 40,114 residents and a median age of 38.5 years, making it the #1,202 most populous county out of 3,222 nationwide. In terms of economic indicators, the county has a poverty rate of 11.2%. The median home value is $145,500, and the median household income is $73,315, which is 2% below the national median.
Demographics
Marshall County has a population of 40,114, making it the #1,202 most populous county in the US. The median age is 38.5 years, which is 1.0% below 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 Marshall County is $73,315, ranking #955 out of 3,222 counties — 2.4% below the national median. The poverty rate is 11.2% and unemployment stands at 4.3%.
Median Household Income Trend
Rankings →Income Distribution
Industry of Employment
Occupation
Housing
The median home value in Marshall County is $145,500 (-48.4% vs national). Renters pay a median of $885/mo and the homeownership rate is 75.0%.
Median Home Value Trend
Rankings →Household Type
Education
In Marshall County, 22.6% of adults age 25+ hold a bachelor's degree or higher, which is 33.1% below the national average, ranking #1,569 out of 3,222 counties.
Bachelor's Degree or Higher Trend
Rankings →Health & Wellbeing
Life expectancy in Marshall County is 74.9 years. 18.5% of adults report poor or fair health and 6.9% lack health insurance. Data from County Health Rankings (2025).
Life Expectancy Trend
Substance Use
17.2% of adults in Marshall County smoke , 40.7% are obese , and 22.7% report excessive drinking. The drug overdose death rate is 10.9 per 100,000.
Adult Smoking Trend
Safety
The suicide rate is 17.4 per 100,000. Motor vehicle deaths occur at a rate of 17.9 per 100,000.
Suicide Rate Trend
Families & Children
15.7% of children in Marshall County live in poverty and the infant mortality rate is 7.7 per 1,000 live births. The teen birth rate is 23.3 per 1,000 females age 15–19.
Infant Mortality Trend
Civic & Transportation
Voter turnout in Marshall County is 67.8%. The mean commute time is 21.8 min, which is 21.1% below the national average.
Voter Turnout Trend
Mean Commute Time Trend
Rankings →Elections
In the 2024 presidential election, Marshall County voted Republican with a margin of 15.6%. The vote was 41.4% Dem / 57% Rep. Compared to 2020, the margin shifted 7.9 toward Republicans .
Vote Share Over Time
About Marshall County, Iowa
Marshall County, Iowa has a total population of 40,114, making it the 1,202nd most populous county in the United States. The median age in Marshall County is 38.5 years, which is 1.0% below the national median of 38.9 years.
The median household income in Marshall County is $73,315, which ranks #955 of 3,222 counties nationwide. This is 2.4% below the national median of $75,149. The poverty rate is 11.2%, lower than the national rate of 12.6%. The unemployment rate stands at 4.3%.
The median home value in Marshall County is $145,500, 48.4% below the national median. Renters in Marshall County pay a median gross rent of $885 per month. The homeownership rate is 75.0%, compared to the national rate of 64.4%.
In Marshall County, 22.6% of residents aged 25 and older hold a bachelor's degree or higher, 33.1% below the national average of 33.7%. Health insurance coverage stands at 94.2% of the population. The average commute time for workers is 21.8 min.
Marshall County is a diverse community. The largest racial or ethnic group is White (non-Hispanic) at 66.0% of the population, followed by Hispanic or Latino (24.6%) and Asian (non-Hispanic) (4.1%).
All data for Marshall 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.