Union, Illinois Demographics & Population 2026
During the 2020–2024 ACS period, Union, Illinois had a total population of 624, the 858th largest village in Illinois, with a median household income of $89,844, which is 8% higher than the state average. The poverty rate is 7.5%.
Data vintage: U.S. Census Bureau ACS 2020–2024 5-Year Estimates · refreshed July 2026 · Methodology & source notes
Union Quick Facts
How Union 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 | 753 | 624 | -17.1% |
| Median household income | $100,104 | $89,844 | -10.2% |
| Median home value | $224,600 | $252,200 | +12.3% |
How Union 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: 61 | National average: 61
Education
Educational Attainment (Adults 25+)
Union Rankings in Illinois
Explore Illinois Rankings
Other Cities in McHenry County
| City | Population | Median Income | Poverty | Home Value |
|---|---|---|---|---|
| Crystal Lake | 40,579 | $108,418 | 6.8% | $311,400 |
| Lake in the Hills | 28,800 | $117,151 | 4.1% | $321,900 |
| McHenry | 28,074 | $86,315 | 4.7% | $266,500 |
| Woodstock | 26,147 | $82,758 | 6.0% | $245,700 |
| Cary | 17,923 | $113,026 | 4.8% | $309,800 |
| Harvard | 9,598 | $67,617 | 11.8% | $175,400 |
| Marengo | 7,040 | $73,523 | 15.7% | $229,900 |
| Johnsburg | 6,386 | $121,023 | 12.1% | $328,300 |
| Spring Grove | 5,917 | $134,210 | 1.4% | $398,400 |
| Lakewood | 4,707 | $173,625 | 3.5% | $552,600 |
Cities Similar to Union
These cities in the same state have comparable population and economic profiles.
| City | Population | Median Income | Home Value | Bachelor's+ | Poverty |
|---|---|---|---|---|---|
| Tovey | 629 | $89,000 | $79,100 | 12.5% | 5.3% |
| South Wilmington | 600 | $86,750 | $174,400 | 13.1% | 5.7% |
| Hardin | 663 | $88,875 | $89,000 | 21.7% | 12.6% |
| Matherville | 657 | $86,500 | $134,800 | 17.9% | 7.6% |
| Deer Creek | 654 | $94,375 | $148,900 | 28.2% | 7.8% |
A note before these figures: with a population of 624, Union'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
Union is a small community located in Illinois, within McHenry County. The total population is 624. It ranks as the 858th most populous out of 1,445 Census-designated places in Illinois.
Age Demographics
The median age in Union is 39.0 years. This is about the same as the state median of 39.0 years.
Economy, Income & Housing
The median household income in Union is $89,844. This is 8% higher than the state median of $83,390. It is also 11% higher than the national median of $80,734. The poverty rate stands at 7.5%. This is 36% lower than the state poverty rate of 11.8%. The unemployment rate is 4.7%. This is 20% lower than the state rate of 5.8%. The median home value is $252,200. Housing costs are 4% lower than the state median of $263,300. With a home-value-to-income ratio of just 2.8x, Union is one of the most affordable housing markets in the area. 87.6% of occupied housing units are owner-occupied. This homeownership rate is 31% higher than the state average of 67.1%.
Race & Ethnicity
Union has a predominantly White (non-Hispanic) population, comprising 90.5% of all residents. Hispanic or Latino residents account for 5.5%. The White (non-Hispanic) population is significantly higher than the state average (90.5% vs 58.1%). The Black or African American population (0.8%) is well below the state average of 13.3%. The Hispanic or Latino population (5.5%) is well below the state average of 18.8%. The Asian population (2.1%) is well below the state average of 5.9%.
Education
15.6% of residents aged 25 and older hold a bachelor's degree or higher. This is 59% lower than the state rate of 37.9%. Nationally, 35.7% of adults hold at least a bachelor's degree. The high school graduation rate (or equivalent) is 93.4%.
Data Sources & Methodology
All demographic data for Union, Illinois 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 Illinois state averages and national averages calculated from the same dataset. Rankings reflect the city's position among all 1,445 Census-designated places in Illinois. 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 Union, Illinois?
Union, Illinois has a population of 624 according to the most recent U.S. Census ACS 5-Year Estimates.
What is the median household income in Union, IL?
The median household income in Union is $89,844, which is 11% higher than the national median of $80,734.
What is the poverty rate in Union, IL?
The poverty rate in Union is 7.5%. This means approximately 47 residents live below the federal poverty line.
What is the racial makeup of Union, Illinois?
Union's population is 90.5% White, 0.8% Black, 5.5% Hispanic/Latino, and 2.1% Asian.
What is the median home value in Union, IL?
The median home value in Union is $252,200. The home-value-to-income ratio is 2.8x.
How educated is Union, Illinois?
15.6% of adults (25+) in Union hold a bachelor's degree or higher, and 5.7% hold a graduate or professional degree.