City · Illinois
Alton, Illinois
Alton, city, in Madison County, Illinois. Alton had 25,013 residents on July 1, 2025 by the Census Bureau's estimate, down 2.6% since 2020; the 2020 Census counted 25,676 and the ACS 2020-2024 5-year estimates put it at 25,279 (±33). GEOID 1701114.
Residents, July 2025 estimate
25,013
Census Bureau estimate (no margin published)
2020 Census count: 25,676 · ACS 2020-2024: 25,279 ±33
Median household income
$54,568
±$4,656 (90% margin)
Illinois: $83,390
Median home value
$103,700
±$4,876 (90% margin)
Illinois: $263,300
Median gross rent
$1,015
±$48 (90% margin)
Illinois: $1,274
Where is Alton and what county is it in?
Alton is a city in Madison County, Illinois. It covers 15.7 square miles of land, 1,638 residents per square mile in 2020.
Alton is in the St. Louis, MO-IL metropolitan statistical area, which takes in 15 counties (Census Bureau delineation, July 2023).
Source: 2024 Gazetteer and 2020 place-by-county files, U.S. Census Bureau · Census reference files
How many people live in Alton, and is it growing?
The Census Bureau estimates that 25,013 people lived in Alton on July 1, 2025, down 2.6% since 2020, a steeper fall than Illinois's (−0.8%). The 2020 Census counted 25,676 residents. The 2020-2024 American Community Survey, a five-year sample, puts the population at 25,279 (±33).
| Measure | Alton | Madison County | Change since 2015-2019 |
|---|---|---|---|
| Total population | 25,279 ±33 | 264,238 | −1,361 |
| Households | 10,714 ±390 | 110,134 | −818 |
| Average household size | 2.30 ±0.08 | 2.35 | no clear change |
| Housing units | 12,551 ±431 | 119,168 | −1,238 |
Alton's population since 2000
From 30,496 in 2000 to 25,013 in 2025: down 18.0%. The 2000, 2010 and 2020 figures are census counts, each for Alton 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 Alton?
The median resident of Alton is 38.0 years old; 23.1% are under 18 and 17.2% are 65 or older. The largest group is non-Hispanic white residents at 68.7%, then non-Hispanic Black residents at 19.2%. 2.6% of residents were born outside the United States.
| Measure | Alton | Madison County | Change since 2015-2019 |
|---|---|---|---|
| Median age | 38.0 ±1.3 | 40.2 | no clear change |
| Under 18 years | 23.1% ±1.9 pts | 21.3% | – |
| 65 years and over | 17.2% ±1.4 pts | 18.5% | – |
| Male | 47.4% ±2.1 pts | 48.9% | – |
| Hispanic or Latino (any race) | 3.0% ±0.7 pts | 4.3% | +1.4 pts |
| White alone, not Hispanic | 68.7% ±3.5 pts | 81.8% | no clear change |
| Black or African American alone, not Hispanic | 19.2% ±3.0 pts | 7.7% | −5.7 pts |
| Asian alone, not Hispanic | 1.4% ±1.2 pts | 0.8% | – |
| American Indian and Alaska Native alone, not Hispanic | 0.4% ±0.3 pts | 0.1% | – |
| Native Hawaiian and Other Pacific Islander alone, not Hispanic | 0.0% ±0.1 pts | 0.0% | – |
| Two or more races, not Hispanic | 6.7% ±1.6 pts | 5.0% | – |
| Some other race alone, not Hispanic | 0.6% ±0.4 pts | 0.2% | – |
| Born outside the United States | 2.6% ±1.1 pts | 2.2% | no clear change |
| Speak a language other than English at home (age 5+) | 3.9% ±1.3 pts | 3.6% | – |
| Civilian veterans (age 18+) | 8.3% ±1.2 pts | 8.2% | – |
| With a disability | 21.4% ±1.8 pts | 15.8% | – |
| No health insurance coverage | 6.8% ±1.2 pts | 4.7% | no clear change |
| High school graduate or higher (age 25+) | 91.3% ±2.0 pts | 93.9% | – |
| Bachelor's degree or higher (age 25+) | 21.5% ±2.4 pts | 31.0% | no clear change |
| Graduate or professional degree (age 25+) | 8.2% ±1.4 pts | 11.2% | – |
| Lived in the same house a year earlier | 85.6% ±2.6 pts | 88.5% | – |
| Moved from another state in the past year | 2.4% ±1.0 pts | 2.1% | – |
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 Alton earn?
Half of Alton's 10,714 households earn less than $54,568 a year (±$4,656), against $75,793 in Madison County and $83,390 in Illinois. In 2015-2019 it was $49,487 in 2024 dollars; the margins of error cannot tell the two periods apart. 21.0% of residents live below the poverty line.
| Measure | Alton | Madison County | Change since 2015-2019 |
|---|---|---|---|
| Median household income | $54,568 ±$4,656 | $75,793 | no clear change |
| Mean household income | $67,596 ±$3,425 | $98,419 | – |
| Per capita income | $29,314 ±$1,601 | $41,560 | no clear change |
| People below the poverty line | 21.0% ±3.3 pts | 11.1% | −5.6 pts |
| Children under 18 below the poverty line | 27.9% ±8.8 pts | 13.2% | no clear change |
| Households receiving SNAP | 27.4% ±3.1 pts | 13.7% | – |
| Households with a computer | 94.4% ±1.4 pts | 94.9% | – |
| Households with a broadband subscription | 90.5% ±1.6 pts | 91.0% | – |
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 Alton?
Owners occupy 59.9% of Alton's occupied homes and renters 40.1%. The median owner-occupied home is valued at $103,700 by its owner (±$4,876). The median renter pays $1,015 a month including utilities, and 38.8% of renters pay 35% or more of their income on rent.
| Measure | Alton | Madison County | Change since 2015-2019 |
|---|---|---|---|
| Median home value (owner-occupied) | $103,700 ±$4,876 | $173,000 | no clear change |
| Median gross rent | $1,015 ±$48 | $1,024 | +$64 |
| Renters paying 35% or more of income on rent | 38.8% ±5.3 pts | 37.8% | −9.1 pts |
| Median monthly owner costs, with a mortgage | $1,149 ±$41 | $1,511 | – |
| Owner-occupied homes | 59.9% ±2.9 pts | 74.2% | no clear change |
| Renter-occupied homes | 40.1% ±2.9 pts | 25.8% | – |
| Housing units | 12,551 ±431 | 119,168 | −1,238 |
| Homeowner vacancy rate | 1.3% ±1.2 pts | 1.0% | – |
| Rental vacancy rate | 7.3% ±3.3 pts | 4.1% | – |
| Single-family detached homes | 75.3% ±2.3 pts | 78.9% | – |
| Mobile homes | 2.8% ±0.9 pts | 2.2% | – |
| Built 2020 or later | 0.5% ±0.4 pts | 0.9% | – |
| Built 2010 to 2019 | 1.9% ±0.8 pts | 6.0% | – |
| Built 1939 or earlier | 27.6% ±2.4 pts | 14.6% | – |
| Households with no vehicle | 10.4% ±2.0 pts | 5.7% | – |
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 Alton building?
Builders took permits for 1 new housing units in Alton in 2025 (1 in single-family houses), 0.0 per 1,000 residents against 1.5 across Illinois.
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 Alton work and get to work?
73.8% of Alton's workers drive alone and 9.7% work from home. The average trip to work takes 22.7 minutes. The unemployment rate in 2020-2024 averaged 5.4%.
| Measure | Alton | Madison County | Change since 2015-2019 |
|---|---|---|---|
| In the labor force (age 16+) | 60.9% ±2.2 pts | 62.7% | – |
| Unemployment rate | 5.4% ±1.5 pts | 4.6% | −3.8 pts |
| Drove alone to work | 73.8% ±3.7 pts | 78.1% | – |
| Carpooled | 10.2% ±2.5 pts | 6.6% | – |
| Public transportation | 1.5% ±0.9 pts | 0.6% | – |
| Walked | 2.3% ±1.7 pts | 1.1% | – |
| Worked from home | 9.7% ±2.2 pts | 12.7% | +6.6 pts |
| Mean travel time to work | 22.7 min ±1.4 | 24.9 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 Alton?
10 census tracts lie mostly in Alton, and 5 more reach into it (2020 census blocks). Their median household incomes run from $37,063 (Tract 4026) to $76,479 (Tract 4023).
| Tract | Residents, 2020-2024 | Median household income |
|---|---|---|
| Tract 4020Madison County | 4,303 | $55,104 |
| Tract 4014Madison County | 3,415 | $59,298 |
| Tract 4022Madison County | 2,942 | $63,730 |
| Tract 4015Madison County | 2,670 | $63,385 |
| Tract 4026Madison County | 2,517 | $37,063 |
| Tract 4021Madison County | 2,092 | $38,688 |
| Tract 4023Madison County | 1,923 | $76,479 |
| Tract 4025Madison County | 1,665 | $68,750 |
| Tract 4024Madison County | 1,707 | $39,531 |
| Tract 4017.01Madison County | 2,376 | $45,843 |
| Tract 4027.01Madison County | 6,519 | $69,044 |
| Tract 4028.01Madison County | 3,576 | $105,938 |
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 Alton) · Census block assignment files
How does Alton compare with other places in Illinois?
By the Census Bureau's July 2025 estimates, Alton is the 1,619th-most populous of the 19,476 U.S. incorporated places that have one and the 90th-most populous of 1,294 in Illinois.
Alton ranks 1,210th of 1,380 places in Illinois with 1,000 or more residents and a reliable estimate, by median household income.
| Measure | Rank | Of |
|---|---|---|
| Population, July 2025 estimate | 90th | 1,294 |
| Growth 2020-2025 (PEP) | 871st | 1,347 |
| Residents per square mile | 381st | 1,383 |
| Median household income | 1,210th | 1,380 |
| Per capita income | 1,209th | 1,383 |
| Median home value | 1,149th | 1,379 |
| Median gross rent | 550th | 1,280 |
| Poverty rate | 109th | 1,119 |
| Bachelor's degree or higher | 800th | 1,369 |
| Median age | 1,048th | 1,383 |
| Owner-occupied share | 1,280th | 1,382 |
| Work from home | 615th | 1,015 |
| Travel time to work | 942nd | 1,382 |
Alton's figures with every place in Illinois (CSV)
Every place in Illinois, sortable · Compare Alton 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 Alton?
7 of the 57 figures for Alton 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 Alton 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' public schools in Alton.