Johnson County, Iowa Population 2026
Updated April 2026 · US Census ACS 2023 5-Year Estimates · 4th-largest in Iowa
The population of Johnson County, Iowa is 154,881 as of the 2023 American Community Survey, making it the 4th-largest county in Iowa. The median household income is $74,721, the median home value is $293,100, and the median age is 30.8.
The population of Johnson County has grown 21.9% since 2010 (131,344 → 160,080), a +1.42% annualized rate.
154,881
Population
+1.42%
Annual growth
253
People / sq mi
$74,721
Median Income
$293,100
Median Home Value
Johnson County covers 613 sq mi of land at 252.7 people per square mile.
About Johnson County, IA
Johnson County is a county in Iowa with a population of 154,881. It ranks #4 among counties in Iowa by population. The median age is 30.8, younger than the national median. The population is 49.7% male and 50.3% female.
The median household income in Johnson County is $74,721, near the US median of $74,580. 6.1% of residents live below the federal poverty level. Home values sit at a median of $293,100, with monthly rent averaging $1,104. The homeownership rate of 58.8% is lower than the national rate of 64.8%.
Educational attainment in Johnson County reflects 54.6% of adults 25 and older holding a bachelor's degree or higher, above the national average of 34.3%. Roughly 12.6% of workers primarily work from home, similar to the national work-from-home rate of 14.2%. The average commute is 19.7 minutes each way.
Johnson County Population History (2010-2024)
The county of Johnson County had a population of 131,344 in 2010 and 160,080 in 2024, a 21.9% growth over 14 years. The peak was 160,080 in 2024. Average annual growth rate: 1.42%.
160,080
Population (2024)
131,344
Population (2010)
160,080
Peak (2024)
1.42%
Avg Annual Growth
| Year | Population |
|---|---|
| 2010 | 131,344 |
| 2011 | 134,125 |
| 2012 | 137,180 |
| 2013 | 140,266 |
| 2014 | 142,874 |
| 2015 | 145,114 |
| 2016 | 147,167 |
| 2017 | 149,703 |
| 2018 | 151,003 |
| 2019 | 152,480 |
| 2020 | 153,052 |
| 2021 | 155,047 |
| 2022 | 156,815 |
| 2023 | 158,202 |
| 2024 | 160,080 |
Race & Ethnicity
| White | 77.6% |
| Black or African American | 7.6% |
| Asian | 0.0% |
| Hispanic or Latino (any race) | 1.3% |
| Two or More Races | 0.0% |
Age & Sex
30.8
Median Age
50.3%
Female
49.7%
Male
12.9%
Age 65+
Age Distribution
Children (under 15): 16.3% · Seniors (65+): 12.9%
Income & Poverty
| Median household income | $74,721+$1,574 vs state |
| Mean household income | $108,967 |
| Per-capita income | $44,699 |
| Poverty rate | 6.1%-0.8% vs state |
| Unemployment rate | 2.5% |
| Employment-to-population | 67.1% |
Top Industries by Employment
The largest employment sector in Johnson County is professional & business services, accounting for 40.7% of workers.
How residents commute
4.1%
Drive alone
7.9%
Carpool
64.9%
Public transit
12.6%
Work from home
19.7 min
Avg commute
Housing
$293,100+$97,200 vs state
Median home value
$1,104
Median rent
58.8%
Homeownership rate
67,211
Total housing units
92.6%
Occupied
7.4%
Vacant
41.2%
Renter-occupied
Social & access
94.9%
With health insurance
96.6%
With broadband internet
31.3%
Foreign-born
3.9%
Veterans (18+)
9.5%
With a disability
84.5%
Speak language other than English at home
Education
96.2%
High School+
54.6%
Bachelor's+
Largest cities in Iowa
Other counties in Iowa
Part of Iowa
Metro areas in Iowa
County rankings
Frequently Asked Questions
Johnson County, Iowa has a population of 154,881 according to the US Census Bureau's 2023 American Community Survey 5-year estimates, making it the 4th-largest county in Iowa. Population density is 253 people per square mile.
The population of Johnson County has grown 21.9% since 2010 (131,344 → 160,080), a +1.42% annualized rate.
The median household income in Johnson County, Iowa is $74,721, with mean (average) household income of $108,967 and per-capita income of $44,699. 6.1% of residents live below the federal poverty level.
In Johnson County, the largest racial and ethnic groups are White (77.6%), Black or African American (7.6%), Hispanic or Latino (1.3%). Figures are from the US Census Bureau's 2023 ACS 5-year estimates and reflect self-reported responses.
The median age in Johnson County, Iowa is 30.8 years. Residents are 50.3% female and 49.7% male.
The median home value in Johnson County is $293,100 and median monthly rent is $1,104. 58.8% of occupied housing units are owner-occupied. The county has 67,211 total housing units, 7.4% of which are vacant.
The largest employment sector in Johnson County, Iowa is professional, scientific, and management services, employing 40.7% of workers. The unemployment rate is 2.5%.
Des Moines is among the largest cities associated with Johnson 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.