Demographics of Alton city, Illinois

Alton city, Illinois had 25,013 people on July 1, 2025, by the Census Bureau’s estimate: −627 since July 2020. Age, income, poverty, housing and origin below come from the survey, averaged over 2020–2024, each with its margin of error.

Alton city, in four figures

25,013
Population: July 1, 2025, Vintage 2025 estimate. The survey’s 2020–⁠2024 figure is 25,279 ±33.; −2.4%
Change since July 2020: −627 people.; 38.0 ±1.3
Median age: ACS 2020–⁠2024.; $54,568 ±$4,656
Median household income: ACS 2020–⁠2024, in 2024 dollars.

Population, year by year

July 1 estimates from the Census Bureau’s Vintage 2025. The Bureau publishes no births, deaths or migration for a place, so the change is the difference between one July estimate and the next.

Alton city, Illinois's population shrank 2.4% from July 2020 to July 2025, against +3.1% nationally

The July 1 estimate of Alton city, Illinois's resident population and the nation's, each year of the Census Bureau's Vintage 2025, as a share of its July 2020 level (= 100).

Source: The Census Bureau

About this chart

The figures

Alton city, Illinois's population shrank 2.4% from July 2020 to July 2025, against +3.1% nationally. The July 1 estimate of Alton city, Illinois's resident population and the nation's, each year of the Census Bureau's Vintage 2025, as a share of its July 2020 level (= 100).
July 1	Population	Index	United States
2020	25,640	100.0	100.0
2021	25,468	99.3	100.2
2022	25,269	98.6	100.7
2023	25,133	98.0	101.6
2024	25,049	97.7	102.5
2025	25,013	97.6	103.1

Population of Alton city, Illinois on July 1 of each year, Vintage 2025
July 1	Population	Change
2020	25,640	—
2021	25,468	−172
2022	25,269	−199
2023	25,133	−136
2024	25,049	−84
2025	25,013	−36

Age, 2020–2024

The median age is 38.0 ±1.3: for men 36.9 ±2.7 and for women 39.0 ±2.9. Shares are of everyone the survey counts, in the Bureau’s sex-by-age table (B01001).

2 more columns on a wider screen

People in Alton city by age, ACS 2020–2024
Age	People	Share	Illinois	United States
Under 5	1,267 ±237	5.0% ±0.9	5.4% ±<0.1	5.6% ±<0.1
5 to 17	4,572 ±458	18.1% ±1.8	16.4% ±0.1	16.3% ±<0.1
18 to 24	1,789 ±340	7.1% ±1.3	9.1% ±<0.1	9.1% ±<0.1
25 to 44	7,362 ±599	29.1% ±2.4	26.9% ±0.1	26.9% ±<0.1
45 to 64	5,935 ±488	23.5% ±1.9	25.2% ±0.1	24.8% ±<0.1
65 and over	4,354 ±391	17.2% ±1.5	17.0% ±0.1	17.2% ±<0.1

Income and poverty, 2020–2024

Median household income is $54,568 ±$4,656, and income per person $29,314 ±$1,601, in 2024 dollars. The median is $83,390 ±$362 in Illinois and $80,734 ±$166 in the United States.

Households by income

2 more columns on a wider screen

Households in Alton city by income, ACS 2020–2024
Household income	Households	Share	Illinois	United States
Under $25,000	2,404 ±329	22.4% ±3.0	14.6% ±0.1	14.6% ±<0.1
$25,000 to $49,999	2,622 ±356	24.5% ±3.2	16.0% ±0.2	16.7% ±<0.1
$50,000 to $74,999	1,920 ±293	17.9% ±2.7	14.8% ±0.1	15.5% ±<0.1
$75,000 to $99,999	1,347 ±235	12.6% ±2.1	12.6% ±0.1	12.6% ±<0.1
$100,000 to $149,999	1,455 ±245	13.6% ±2.2	18.0% ±0.2	17.5% ±<0.1
$150,000 to $199,999	644 ±156	6.0% ±1.4	10.1% ±0.1	9.6% ±<0.1
$200,000 or more	322 ±122	3.0% ±1.1	13.8% ±0.1	13.4% ±0.1

Poverty by age

The poverty rate is the share of people whose family income is below the federal threshold for their family’s size, of everyone for whom the Bureau determines it (B17020).

2 more columns on a wider screen

Poverty rate in Alton city by age, ACS 2020–2024
Age	Below poverty	Rate	Illinois	United States
All ages	5,203 ±825	21.0% ±3.3	11.8% ±0.1	12.5% ±0.1
Under 18	1,578 ±386	27.9% ±6.1	15.1% ±0.2	16.1% ±0.1
18 to 59	2,654 ±397	20.0% ±2.8	11.0% ±0.1	11.6% ±0.1
60 and over	971 ±232	16.8% ±3.7	10.6% ±0.1	11.0% ±<0.1

Housing, 2020–2024

1 more column on a wider screen

Housing in Alton city, ACS 2020–2024
Measure	Alton city	Illinois	United States
Housing units	12,551 ±431	5,457,452 ±471	143,775,355 ±10,234
Occupied	85.4% ±1.0	92.3% ±0.1	89.9% ±0.1
Vacant	14.6% ±1.8	7.7% ±0.1	10.1% ±0.1
Owner occupied	59.9% ±2.8	67.1% ±0.3	65.2% ±0.3
Renter occupied	40.1% ±3.1	32.9% ±0.2	34.8% ±0.1
Median home value	$103,700 ±$4,876	$263,300 ±$797	$332,700 ±$236
Median gross rent	$1,015 ±$48	$1,274 ±$5	$1,413 ±$2
Median year built	1953 ±2	1971 ±2	1980 ±1

Occupied and vacant are shares of all housing units; owner and renter occupied are shares of occupied units. Value and rent are medians in 2024 dollars.

Origin and place of birth, 2020–2024

Hispanic or Latino origin is not a race in the Census Bureau’s tables. Here the people of Hispanic origin, of any race, are one row, and everyone else is counted by race alone (B03002), so the rows add to the whole.

Hispanic origin and race

2 more columns on a wider screen

People in Alton city by Hispanic origin and race, ACS 2020–2024
Origin	People	Share	Illinois	United States
Hispanic or Latino	760 ±174	3.0% ±0.7	18.8% ±<0.1	19.3% ±<0.1
White alone, not Hispanic	17,377 ±874	68.7% ±3.5	58.1% ±<0.1	57.4% ±<0.1
Black alone, not Hispanic	4,842 ±748	19.2% ±3.0	13.3% ±<0.1	11.9% ±<0.1
Asian alone, not Hispanic	55 to 673	0.2% to 2.7%	5.9% ±<0.1	5.9% ±<0.1
American Indian and Alaska Native alone, not Hispanic	18 to 180	0.1% to 0.7%	0.1% ±<0.1	0.5% ±<0.1
Native Hawaiian and Other Pacific Islander alone, not Hispanic	0 to 24	0% to 0.1%	< 0.1% ±<0.1	0.2% ±<0.1
Some other race alone, not Hispanic	39 to 255	0.2% to 1.0%	0.4% ±<0.1	0.6% ±<0.1
Two or more races, not Hispanic	1,690 ±409	6.7% ±1.6	3.4% ±0.1	4.3% ±<0.1

A range (the estimate less and plus its margin) where the Bureau's estimate is too uncertain to state as one number: a coefficient of variation over 30%.

Place of birth and citizenship

“Born a citizen outside the states” counts people born in Puerto Rico, the island areas, or abroad to American parents. Naturalized citizens and those who are not citizens together make up the people born abroad (B05002).

2 more columns on a wider screen

People in Alton city by place of birth and citizenship, ACS 2020–2024
Born	People	Share	Illinois	United States
Born in the state	17,401 ±508	68.8% ±2.0	66.5% ±0.1	57.3% ±<0.1
Born in another state	7,042 ±590	27.9% ±2.3	17.5% ±0.1	26.9% ±<0.1
Born a citizen outside the states	81 to 269	0.3% to 1.1%	1.3% ±<0.1	1.7% ±<0.1
Born abroad	661 ±283	2.6% ±1.1	14.7% ±0.1	14.1% ±<0.1
Naturalized citizens	420 ±198	1.7% ±0.8	7.7% ±0.1	7.4% ±<0.1
Not citizens	90 to 392	0.4% to 1.6%	7.0% ±0.1	6.8% ±<0.1

A range (the estimate less and plus its margin) where the Bureau's estimate is too uncertain to state as one number: a coefficient of variation over 30%.

Alton city among the places of Illinois

87th of 337 places of 5,000 or more by the survey’s 2020–2024 count. Every one is listed on the Illinois page.

Places of Illinois near Alton city in population, ACS 2020–2024
Place	ACS 2020–⁠2024
Granite City city	26,549 ±465
Edwardsville city	26,474 ±291
Lockport city	26,409 ±45
Woodstock city	26,147 ±365
West Chicago city	25,395 ±51
Alton city	25,279 ±33
Belvidere city	24,752 ±563
Morton Grove village	24,619 ±45
Zion city	24,600 ±39
Melrose Park village	24,549 ±637
Homer Glen village	24,529 ±78

Rankings this appears in

No. 6 Places in Illinois by poverty rate
No. 113 Places in Illinois by median age
No. 190 Places in Illinois by median rent
No. 210 Places in Illinois by foreign-born share
No. 213 Places in Illinois by homeownership rate
No. 228 Places in Illinois by median household income

Sources

Census Bureau population estimates — incorporated places and New England towns — U.S. Census Bureau · U.S. Government work · retrieved September 25, 2026
American Community Survey 5-year estimates — table-based Summary File · U.S. Government work

Compiled automatically from Census Bureau population estimates — incorporated places and New England towns and American Community Survey 5-year estimates — table-based Summary File by a checked SQL query · Editor: Kian O'Connor · How this site is built

Data retrieved September 25, 2026