Town · Maine
Union, Maine
Union, town, in Knox County, Maine. Union had 2,444 residents on July 1, 2025 by the Census Bureau's estimate, up 3.1% since 2020; the 2020 Census counted 2,383 and the ACS 2020-2024 5-year estimates put it at 2,663 (±365). GEOID 2301378115.
Residents, July 2025 estimate
2,444
Census Bureau estimate (no margin published)
2020 Census count: 2,383 · ACS 2020-2024: 2,663 ±365
Median household income
$80,724
±$8,800 (90% margin)
Maine: $74,733
Median home value
$267,600
±$42,150 (90% margin)
Maine: $296,600
Median gross rent
$1,179
±$452 (90% margin)
Maine: $1,139
Where is Union and what county is it in?
Union is a town in Knox County, Maine. It covers 32.2 square miles of land, 74 residents per square mile in 2020.
Source: 2024 Gazetteer and 2020 place-by-county files, U.S. Census Bureau · Census reference files
How many people live in Union, and is it growing?
The Census Bureau estimates that 2,444 people lived in Union on July 1, 2025, up 3.1% since 2020, slower than Maine (+3.8%). The 2020 Census counted 2,383 residents. The 2020-2024 American Community Survey, a five-year sample, puts the population at 2,663 (±365).
| Measure | Union | Knox County | Change since 2015-2019 |
|---|---|---|---|
| Total population | 2,663±365 | 41,003 | no clear change |
| Households | 1,060±140 | 18,484 | no clear change |
| Average household size | 2.49±0.24 | 2.12 | no clear change |
| Housing units | 1,299±148 | 24,564 | no clear change |
Union's population since 2000
From 2,209 in 2000 to 2,444 in 2025: up 10.6%. The 2000, 2010 and 2020 figures are census counts, each for Union as it was drawn that year: a place that annexed land, or a community that has since incorporated, covered a different area then. The 2005 figure is the Census Bureau's intercensal estimate, revised to fit the 2000 and 2010 counts and drawn on 2010 boundaries; 2015 and 2025 are July 1 estimates made from the census before them.
Source: The 2000, 2010 and 2020 Census counts and the Census Bureau's population estimates (intercensal 2000-2010, Vintage 2020, Vintage 2025) · Census population estimates
Source: American Community Survey 2020-2024 5-year estimates, U.S. Census Bureau (released January 2026); Census PEP Vintage 2025 (SUB-EST2025, CO-EST2025); 2020 Census P.L. 94-171 · Check it at data.census.gov
Who lives in Union?
The median resident of Union is 41.6 years old; 24.9% are under 18 and 21.4% are 65 or older. The largest group is non-Hispanic white residents at 94.7%, then non-Hispanic residents of two or more races at 3.6%.
| Measure | Union | Knox County | Change since 2015-2019 |
|---|---|---|---|
| Median age | 41.6±5.3 | 49.5 | no clear change |
| Under 18 years | 24.9%±4.8 pts | 16.8% | – |
| 65 years and over | 21.4%±4.4 pts | 27.9% | – |
| Male | 50.7%±3.5 pts | 50.2% | – |
| Hispanic or Latino (any race) | 0.0%±1.0 pts | 1.9% | – |
| White alone, not Hispanic | 94.7%±2.7 pts | 93.2% | no clear change |
| Black or African American alone, not Hispanic | 0.0%±1.0 pts | 0.3% | – |
| Asian alone, not Hispanic | 0.0%±1.0 pts | 0.5% | – |
| American Indian and Alaska Native alone, not Hispanic | 0.5%±0.6 pts | 0.1% | – |
| Native Hawaiian and Other Pacific Islander alone, not Hispanic | 0.0%±1.0 pts | 0.0% | – |
| Two or more races, not Hispanic | 3.6%±1.6 pts | 3.8% | – |
| Some other race alone, not Hispanic | 1.2%±1.8 pts | 0.2% | – |
| Born outside the United States | 0.9%±1.0 pts | 3.1% | – |
| Speak a language other than English at home (age 5+) | 0.4%±0.7 pts | 4.2% | – |
| Civilian veterans (age 18+) | 9.8%±3.0 pts | 8.7% | – |
| With a disability | 11.2%±3.3 pts | 13.0% | – |
| No health insurance coverage | 7.4%±3.9 pts | 5.5% | no clear change |
| High school graduate or higher (age 25+) | 97.5%±2.6 pts | 94.8% | – |
| Bachelor's degree or higher (age 25+) | 34.4%±5.8 pts | 39.7% | +9.9 pts |
| Graduate or professional degree (age 25+) | 9.6%±3.7 pts | 15.3% | – |
| Lived in the same house a year earlier | 97.9%±1.7 pts | 90.3% | – |
| Moved from another state in the past year | 0.2%±0.3 pts | 3.1% | – |
Source: American Community Survey 2020-2024 5-year estimates, U.S. Census Bureau (released January 2026) (Data Profiles DP02, DP05) · Check it at data.census.gov
What do households in Union earn?
Half of Union's 1,060 households earn less than $80,724 a year (±$8,800), against $74,096 in Knox County and $74,733 in Maine. In 2015-2019 it was $76,323 in 2024 dollars; the margins of error cannot tell the two periods apart. 10.2% of residents live below the poverty line.
| Measure | Union | Knox County | Change since 2015-2019 |
|---|---|---|---|
| Median household income | $80,724±$8,800 | $74,096 | no clear change |
| Mean household income | $97,941±$12,917 | $99,101 | – |
| Per capita income | $39,432±$5,601 | $44,763 | +$8,346 |
| People below the poverty line | 10.2%±5.5 pts | 8.2% | no clear change |
| Children under 18 below the poverty line | 17.0%±16.0 pts | 6.4% | – |
| Households receiving SNAP | 13.3%±7.1 pts | 8.5% | – |
| Households with a computer | 95.9%±3.3 pts | 94.8% | – |
| Households with a broadband subscription | 90.5%±5.7 pts | 90.3% | – |
Source: American Community Survey 2020-2024 5-year estimates, U.S. Census Bureau (released January 2026) (Data Profile DP03) · Check it at data.census.gov
What does housing cost in Union?
Owners occupy 85.9% of Union's occupied homes and renters 14.1%. The median owner-occupied home is valued at $267,600 by its owner (±$42,150). The median renter pays $1,179 a month including utilities.
| Measure | Union | Knox County | Change since 2015-2019 |
|---|---|---|---|
| Median home value (owner-occupied) | $267,600±$42,150 | $324,900 | no clear change |
| Median gross rent | $1,179±$452 | $1,165 | no clear change |
| Renters paying 35% or more of income on rent | 15.1%±16.2 pts | 36.3% | – |
| Median monthly owner costs, with a mortgage | $1,696±$115 | $1,691 | – |
| Owner-occupied homes | 85.9%±6.9 pts | 78.7% | no clear change |
| Renter-occupied homes | 14.1%±6.9 pts | 21.3% | – |
| Housing units | 1,299±148 | 24,564 | no clear change |
| Homeowner vacancy rate | 0.0%±3.0 pts | 0.9% | – |
| Rental vacancy rate | 0.0%±16.8 pts | 3.3% | – |
| Single-family detached homes | 84.1%±5.8 pts | 79.4% | – |
| Mobile homes | 11.6%±5.6 pts | 5.8% | – |
| Built 2020 or later | 0.5%±0.7 pts | 0.6% | – |
| Built 2010 to 2019 | 10.7%±5.0 pts | 5.3% | – |
| Built 1939 or earlier | 32.9%±8.1 pts | 32.9% | – |
| Households with no vehicle | 2.1%±2.7 pts | 5.4% | – |
Source: American Community Survey 2020-2024 5-year estimates, U.S. Census Bureau (released January 2026) (Data Profile DP04) · Check it at data.census.gov
How many new homes is Union building?
Builders took permits for 9 new housing units in Union in 2025 (9 in single-family houses), 3.7 per 1,000 residents against 4.9 across Maine.
Counts of units in permits a local office issued; not every permitted unit is built. A year marked with months was reported for part of the year.
Source: Building Permits Survey, annual place files 2019-2025, U.S. Census Bureau · Census Building Permits Survey
How do people in Union work and get to work?
72.0% of Union's workers drive alone and 15.9% work from home. The average trip to work takes 29.4 minutes.
| Measure | Union | Knox County | Change since 2015-2019 |
|---|---|---|---|
| In the labor force (age 16+) | 65.0%±5.0 pts | 58.1% | – |
| Unemployment rate | 3.2%±2.4 pts | 3.9% | – |
| Drove alone to work | 72.0%±7.6 pts | 68.8% | – |
| Carpooled | 9.5%±5.0 pts | 9.4% | – |
| Public transportation | 0.0%±2.1 pts | 0.1% | – |
| Walked | 2.6%±2.2 pts | 3.5% | – |
| Worked from home | 15.9%±5.9 pts | 16.6% | +11.4 pts |
| Mean travel time to work | 29.4 min±4.5 | 19.6 min | no clear change |
Source: American Community Survey 2020-2024 5-year estimates, U.S. Census Bureau (released January 2026) (Data Profile DP03) · Check it at data.census.gov
What census tracts are in Union?
1 census tract lies mostly in Union (2020 census blocks).
| Tract | Residents, 2020-2024 | Median household income |
|---|---|---|
| Tract 9703.02Knox County | 4,287 | $74,815 |
Source: American Community Survey 2020-2024 5-year estimates, U.S. Census Bureau (released January 2026); 2020 block assignment files (tract share = share of the tract's census blocks in Union) · Census block assignment files
How does Union compare with other places in Maine?
By the Census Bureau's July 2025 estimates, Union is the 4,169th-most populous of the 16,079 U.S. towns and townships that have one and the 121st-most populous of 454 in Maine.
Union ranks 124th of 349 places in Maine with 1,000 or more residents and a reliable estimate, by median household income.
| Measure | Rank | Of |
|---|---|---|
| Population, July 2025 estimate | 121st | 454 |
| Growth 2020-2025 (PEP) | 150th | 273 |
| Residents per square mile | 233rd | 353 |
| Median household income | 124th | 349 |
| Per capita income | 181st | 353 |
| Median home value | 169th | 352 |
| Median gross rent | 99th | 301 |
| Poverty rate | 156th | 277 |
| Bachelor's degree or higher | 139th | 352 |
| Median age | 271st | 353 |
| Owner-occupied share | 117th | 353 |
| Work from home | 131st | 275 |
| Travel time to work | 106th | 352 |
Union's figures with every place in Maine (CSV)
Every place in Maine, sortable · Compare Union with other places
Source: PlainCities ranks computed from the American Community Survey 2020-2024 5-year estimates, U.S. Census Bureau (released January 2026) and PEP Vintage 2025 · How ranks are computed
How reliable are the figures for Union?
18 of the 57 figures for Union on this page carry a coefficient of variation over 40% and are marked with a ring: they come from a small sample, so read them as rough.
The American Community Survey samples about one household in eight over five years, so every figure is an estimate with a 90% margin of error (shown under each value). A ring marks an estimate whose coefficient of variation is over 40%. A change is called only when the gap between the two periods is larger than their combined 90% margin (the square root of the sum of the two squared margins), the Census Bureau's test. How to read a margin of error.
Source: American Community Survey 2020-2024 5-year estimates, U.S. Census Bureau (released January 2026): margins of error as published · ACS technical documentation
How these figures are made: methodology and release checks · reading a margin of error · every state · corrections
Not on this page: crime, weather and schools for Union are other agencies' records. Crime: the FBI's Crime Data Explorer · climate: NOAA's U.S. Climate Normals · schools: the National Center for Education Statistics' school search.