Janesville, Iowa Demographics & Population 2026
During the 2020–2024 ACS period, Janesville, Iowa had a total population of 917, the 310th largest city in Iowa, with a median household income of $103,542, which is 38% higher than the state average. The poverty rate is 5.5%.
Data vintage: U.S. Census Bureau ACS 2020–2024 5-Year Estimates · refreshed July 2026 · Methodology & source notes
Key Takeaways
- Household income is 38% above the state average — one of the wealthiest communities in Iowa.
- Housing is very affordable with a home-value-to-income ratio of just 2.1x.
Janesville Quick Facts
How Janesville Changed
Change from the 2019–2023 ACS period to 2020–2024. These are rolling five-year estimates, not year-over-year measurements.
| Metric | 2019–2023 | 2020–2024 | Change |
|---|---|---|---|
| Population | 1,012 | 917 | -9.4% |
| Median household income | $84,231 | $103,542 | +22.9% |
| Median home value | $214,700 | $221,700 | +3.3% |
How Janesville Compares
Median Household Income
Median Home Value
Economy & Housing
Household Income Distribution
Detailed income brackets
Employment
Housing Overview
People & Demographics
Age Distribution
Race & Ethnicity
Diversity Index
A less diverse community where one racial or ethnic group represents a large majority.
State average: 31 | National average: 61
Education
Educational Attainment (Adults 25+)
Janesville Rankings in Iowa
Explore Iowa Rankings
Other Cities in Black Hawk County
| City | Population | Median Income | Poverty | Home Value |
|---|---|---|---|---|
| Waterloo | 67,008 | $57,480 | 16.6% | $152,600 |
| Cedar Falls | 40,888 | $76,987 | 15.7% | $263,600 |
| Evansdale | 4,518 | $60,397 | 24.0% | $150,300 |
| Hudson | 2,699 | $120,481 | 4.0% | $242,700 |
| Jesup | 2,561 | $89,408 | 7.0% | $190,200 |
| La Porte City | 2,071 | $70,500 | 10.8% | $163,200 |
| Elk Run Heights | 964 | $76,500 | 4.0% | $171,200 |
| Raymond | 899 | $76,711 | 4.3% | $222,600 |
| Dunkerton | 821 | $86,413 | 7.0% | $189,700 |
| Gilbertville | 761 | $79,583 | 3.1% | $197,400 |
Cities Similar to Janesville
These cities in the same state have comparable population and economic profiles.
| City | Population | Median Income | Home Value | Bachelor's+ | Poverty |
|---|---|---|---|---|---|
| Underwood | 898 | $105,341 | $253,500 | 35.1% | 3.3% |
| Maxwell | 905 | $97,639 | $184,600 | 28.9% | 4.1% |
| Hinton | 931 | $114,531 | $263,100 | 28.2% | 1.4% |
| Arnolds Park | 922 | $86,833 | $438,900 | 39.1% | 6.0% |
| Lake Panorama | 928 | $126,563 | $388,600 | 48.2% | 4.9% |
A note before these figures: with a population of 917, Janesville's ACS estimates come from a small number of survey responses and carry wide margins of error. Individual percentages below — particularly rates that round to 0% or 100% — are approximations, not precise measurements. See data.census.gov for the published margins of error.
Population Overview
Janesville is a small community located in Iowa, within Black Hawk County. The total population is 917. It ranks as the 310th most populous out of 1,017 Census-designated places in Iowa.
Age Demographics
The median age in Janesville is 47.0 years. This is 22% higher than the state median of 38.6 years.
Economy, Income & Housing
The median household income in Janesville is $103,542. This is 38% higher than the state median of $75,059. It is also 28% higher than the national median of $80,734. The poverty rate stands at 5.5%. This is 51% lower than the state poverty rate of 11.1%. The unemployment rate is 2.9%. This is 19% lower than the state rate of 3.6%. The median home value is $221,700. Housing costs are 7% higher than the state median of $208,000. With a home-value-to-income ratio of just 2.1x, Janesville is one of the most affordable housing markets in the area. 91.4% of occupied housing units are owner-occupied. This homeownership rate is 27% higher than the state average of 71.7%.
Race & Ethnicity
Janesville has a predominantly White (non-Hispanic) population, comprising 97.4% of all residents. Asian residents account for 1.1%. The Hispanic or Latino population (0.4%) is well below the state average of 7.3%. The Asian population (1.1%) is well below the state average of 2.5%.
Education
28.9% of residents aged 25 and older hold a bachelor's degree or higher. This is 8% lower than the state rate of 31.4%. Nationally, 35.7% of adults hold at least a bachelor's degree. The high school graduation rate (or equivalent) is 98.7%.
Data Sources & Methodology
All demographic data for Janesville, Iowa is sourced from the U.S. Census Bureau's American Community Survey (ACS) 2020–2024 5-Year Estimates. The ACS collects data from approximately 3.5 million households annually and pools five years of responses so that even small communities can be measured, though the margin of error widens as the population falls. Comparisons are made against Iowa state averages and national averages calculated from the same dataset. Rankings reflect the city's position among all 1,017 Census-designated places in Iowa. Read more about how these figures are produced on our methodology page, or visit data.census.gov for official data.
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Frequently Asked Questions
What is the population of Janesville, Iowa?
Janesville, Iowa has a population of 917 according to the most recent U.S. Census ACS 5-Year Estimates.
What is the median household income in Janesville, IA?
The median household income in Janesville is $103,542, which is 28% higher than the national median of $80,734.
What is the poverty rate in Janesville, IA?
The poverty rate in Janesville is 5.5%. This means approximately 50 residents live below the federal poverty line.
What is the racial makeup of Janesville, Iowa?
Janesville's population is 97.4% White, 0.0% Black, 0.4% Hispanic/Latino, and 1.1% Asian.
What is the median home value in Janesville, IA?
The median home value in Janesville is $221,700. The home-value-to-income ratio is 2.1x.
How educated is Janesville, Iowa?
28.9% of adults (25+) in Janesville hold a bachelor's degree or higher, and 4.6% hold a graduate or professional degree.