Washington County, Iowa Population 2026
Updated April 2026 · US Census ACS 2023 5-Year Estimates · 27th-largest in Iowa
The population of Washington County, Iowa is 22,539 as of the 2023 American Community Survey, making it the 27th-largest county in Iowa. The median household income is $71,339, the median home value is $199,600, and the median age is 40.3.
The population of Washington County has grown 4.4% since 2010 (21,687 → 22,631), a +0.30% annualized rate.
22,539
Population
+0.30%
Annual growth
40
People / sq mi
$71,339
Median Income
$199,600
Median Home Value
Washington County covers 569 sq mi of land at 39.6 people per square mile.
About Washington County, IA
Washington County is a county in Iowa with a population of 22,539. It ranks #27 among counties in Iowa by population. The median age is 40.3, older than the national median. The population is 49.7% male and 50.3% female.
The median household income in Washington County is $71,339, near the US median of $74,580. 6.0% of residents live below the federal poverty level. Home values sit at a median of $199,600, with monthly rent averaging $862. The homeownership rate of 72.2% is higher than the national rate of 64.8%.
Educational attainment in Washington County reflects 24.9% of adults 25 and older holding a bachelor's degree or higher, below the national average of 34.3%. Roughly 8.5% of workers primarily work from home, below the national work-from-home rate of 14.2%. The average commute is 24.2 minutes each way.
Washington County Population History (2010-2024)
The county of Washington County had a population of 21,687 in 2010 and 22,631 in 2024, a 4.4% growth over 14 years. The peak was 22,631 in 2024. Average annual growth rate: 0.31%.
22,631
Population (2024)
21,687
Population (2010)
22,631
Peak (2024)
0.31%
Avg Annual Growth
| Year | Population |
|---|---|
| 2010 | 21,687 |
| 2011 | 21,825 |
| 2012 | 21,910 |
| 2013 | 21,954 |
| 2014 | 22,040 |
| 2015 | 22,160 |
| 2016 | 22,147 |
| 2017 | 22,236 |
| 2018 | 22,095 |
| 2019 | 22,030 |
| 2020 | 22,541 |
| 2021 | 22,526 |
| 2022 | 22,541 |
| 2023 | 22,554 |
| 2024 | 22,631 |
Race & Ethnicity
| White | 91.3% |
| Black or African American | 0.6% |
| Asian | 0.0% |
| Hispanic or Latino (any race) | 1.1% |
| Two or More Races | 0.0% |
Age & Sex
40.3
Median Age
50.3%
Female
49.7%
Male
19.9%
Age 65+
Age Distribution
Children (under 15): 20.3% · Seniors (65+): 19.9%
Income & Poverty
| Median household income | $71,339$-1,808 vs state |
| Mean household income | $92,270 |
| Per-capita income | $37,686 |
| Poverty rate | 6.0%-0.9% vs state |
| Unemployment rate | 1.7% |
| Employment-to-population | 66.4% |
Top Industries by Employment
The largest employment sector in Washington County is professional & business services, accounting for 25.2% of workers.
How residents commute
1.0%
Drive alone
2.5%
Carpool
77.8%
Public transit
8.5%
Work from home
24.2 min
Avg commute
Housing
$199,600+$3,700 vs state
Median home value
$862
Median rent
72.2%
Homeownership rate
9,638
Total housing units
93.9%
Occupied
6.1%
Vacant
27.8%
Renter-occupied
Social & access
92.8%
With health insurance
92.5%
With broadband internet
18.0%
Foreign-born
6.2%
Veterans (18+)
13.5%
With a disability
92.8%
Speak language other than English at home
Education
93.2%
High School+
24.9%
Bachelor's+
Largest cities in Iowa
Other counties in Iowa
Part of Iowa
Metro areas in Iowa
County rankings
Frequently Asked Questions
Washington County, Iowa has a population of 22,539 according to the US Census Bureau's 2023 American Community Survey 5-year estimates, making it the 27th-largest county in Iowa. Population density is 40 people per square mile.
The population of Washington County has grown 4.4% since 2010 (21,687 → 22,631), a +0.30% annualized rate.
The median household income in Washington County, Iowa is $71,339, with mean (average) household income of $92,270 and per-capita income of $37,686. 6.0% of residents live below the federal poverty level.
In Washington County, the largest racial and ethnic groups are White (91.3%), Hispanic or Latino (1.1%), Black or African American (0.6%). Figures are from the US Census Bureau's 2023 ACS 5-year estimates and reflect self-reported responses.
The median age in Washington County, Iowa is 40.3 years. Residents are 50.3% female and 49.7% male.
The median home value in Washington County is $199,600 and median monthly rent is $862. 72.2% of occupied housing units are owner-occupied. The county has 9,638 total housing units, 6.1% of which are vacant.
The largest employment sector in Washington County, Iowa is professional, scientific, and management services, employing 25.2% of workers. The unemployment rate is 1.7%.
Des Moines is among the largest cities associated with Washington County, Iowa, with a population of 212,464.
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Statewide data for Iowa
Population, race, income, age, and trends across Iowa
Data from the American Community Survey (ACS) 5-Year estimates.
Source: U.S. Census Bureau ACS, 2026.