Plymouth County, Iowa
Located in Iowa, Plymouth County has a population of 25,747 residents and a median age of 41.3 years, making it the #1,625 most populous county out of 3,222 nationwide. In terms of economic indicators, the county has a poverty rate of 6.9%. The median home value is $228,900, and the median household income is $83,251, which is 11% above the national median.
Demographics
Plymouth County has a population of 25,747, making it the #1,625 most populous county in the US. The median age is 41.3 years, which is 6.2% 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 Plymouth County is $83,251, ranking #477 out of 3,222 counties — 10.8% above the national median. The poverty rate is 6.9% and unemployment stands at 2.2%.
Median Household Income Trend
Rankings →Income Distribution
Industry of Employment
Occupation
Housing
The median home value in Plymouth County is $228,900 (-18.8% vs national). Renters pay a median of $910/mo and the homeownership rate is 73.6%.
Median Home Value Trend
Rankings →Household Type
Education
In Plymouth County, 21.7% of adults age 25+ hold a bachelor's degree or higher, which is 35.7% below the national average, ranking #1,702 out of 3,222 counties.
Bachelor's Degree or Higher Trend
Rankings →Health & Wellbeing
Life expectancy in Plymouth County is 79.0 years. 14.8% of adults report poor or fair health and 4.6% lack health insurance. Data from County Health Rankings (2025).
Life Expectancy Trend
Substance Use
16.9% of adults in Plymouth County smoke , 37.5% are obese , and 26.2% report excessive drinking. The drug overdose death rate is 13.1 per 100,000.
Adult Smoking Trend
Safety
The suicide rate is 20.3 per 100,000. Motor vehicle deaths occur at a rate of 10.2 per 100,000.
Suicide Rate Trend
Families & Children
10.9% of children in Plymouth County live in poverty . The teen birth rate is 10.2 per 1,000 females age 15–19.
Teen Birth Rate Trend
Civic & Transportation
Voter turnout in Plymouth County is 77.4%. The mean commute time is 21.2 min, which is 23.2% below the national average.
Voter Turnout Trend
Mean Commute Time Trend
Rankings →Elections
In the 2024 presidential election, Plymouth County voted Republican with a margin of 54.2%. The vote was 22.3% Dem / 76.5% Rep. Compared to 2020, the margin shifted 4.9 toward Republicans .
Vote Share Over Time
About Plymouth County, Iowa
Plymouth County, Iowa has a total population of 25,747, making it the 1,625th most populous county in the United States. The median age in Plymouth County is 41.3 years, which is 6.2% above the national median of 38.9 years.
The median household income in Plymouth County is $83,251, which ranks #477 of 3,222 counties nationwide. This is 10.8% above the national median of $75,149. The poverty rate is 6.9%, lower than the national rate of 12.6%. The unemployment rate stands at 2.2%.
The median home value in Plymouth County is $228,900, 18.8% below the national median. Renters in Plymouth County pay a median gross rent of $910 per month. The homeownership rate is 73.6%, compared to the national rate of 64.4%.
In Plymouth County, 21.7% of residents aged 25 and older hold a bachelor's degree or higher, 35.7% below the national average of 33.7%. Health insurance coverage stands at 94.7% of the population. The average commute time for workers is 21.2 min.
Plymouth County is a diverse community. The largest racial or ethnic group is White (non-Hispanic) at 88.0% of the population, followed by Hispanic or Latino (6.4%) and Black (non-Hispanic) (2.4%).
All data for Plymouth 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.