St. Clair

County in Illinois

County

The population development of St. Clair.

Name	Status	Population Census 1990-04-01	Population Census 2000-04-01	Population Census 2010-04-01	Population Census 2020-04-01	Population Estimate 2024-07-01
St. Clair	County	262,852	256,082	270,056	257,631	251,149	→
Illinois	State	11,430,602	12,419,293	12,830,632	12,821,814	12,710,158

Contents: Incorporated Places

The population development of the incorporated places in St. Clair.

The Details icon links to further information about a selected place including its population structure (gender, age groups, age distribution, urbanization, »race«, ethnicity).

Name	Status	County	Population Census 1990-04-01	Population Census 2000-04-01	Population Census 2010-04-01	Population Census 2020-04-01	Population Estimate 2024-07-01
Belleville	City	St. Clair	43,120	42,183	44,239	42,386	40,560	→
Brooklyn	Village	St. Clair	1,144	665	743	652	623	→
Cahokia Heights (incl. Centreville, Cahokia, Alorton)	City	St. Clair	28,052	25,028	22,597	17,903	17,052	→
Caseyville	Village	St. Clair	5,042	4,589	4,209	4,393	4,395	→
Collinsville	City	Madison / St. Clair	23,006	24,673	25,591	24,408	23,766	→
Columbia	City	Monroe / St. Clair	6,089	7,875	9,698	11,012	10,919	→
Dupo	Village	St. Clair / Monroe	3,849	4,021	4,179	3,987	3,797	→
East Carondelet	Village	St. Clair	630	298	506	390	373	→
East St. Louis	City	St. Clair	40,871	31,667	26,938	18,462	17,808	→
Fairmont City	Village	St. Clair / Madison	2,125	2,431	2,645	2,261	2,169	→
Fairview Heights	City	St. Clair	14,952	14,981	17,065	16,714	16,115	→
Fayetteville	Village	St. Clair	303	383	366	295	286	→
Freeburg	Village	St. Clair	3,348	3,975	4,401	4,611	4,518	→
Lebanon	City	St. Clair	3,738	3,558	4,452	4,759	4,628	→
Lenzburg	Village	St. Clair	530	578	516	466	448	→
Madison	City	Madison / St. Clair	5,353	4,539	3,901	3,144	3,060	→
Marissa	Village	St. Clair	2,359	2,165	1,978	1,833	1,743	→
Mascoutah	City	St. Clair	5,656	5,679	7,618	8,799	9,118	→
Millstadt	Village	St. Clair	2,644	2,921	4,006	4,082	3,957	→
New Athens	Village	St. Clair	2,011	1,985	2,062	1,953	1,870	→
New Baden	Village	Clinton / St. Clair	2,722	2,960	3,353	3,427	3,395	→
O'Fallon	City	St. Clair	16,518	21,946	28,767	32,432	32,169	→
Sauget	Village	St. Clair	652	354	167	138	134	→
Shiloh	Village	St. Clair	6,396	8,176	12,595	14,145	14,754	→
Smithton	Village	St. Clair	1,676	2,374	3,738	4,006	3,888	→
St. Libory	Village	St. Clair	531	583	620	631	608	→
Summerfield	Village	St. Clair	499	468	431	344	331	→
Swansea	Village	St. Clair	9,252	11,048	13,446	14,382	14,445	→
Washington Park	Village	St. Clair	7,428	5,347	4,196	2,579	2,481	→

Source: U.S. Census Bureau.

Explanation: Latest available rebased population figures are used. In case of significant changes, they were recalculated by using census block data.

Further information about the population structure:

Gender (C 2020)
Males	124,557
Females	132,843

Age Groups (C 2020)
0-17 years	60,316
18-64 years	154,414
65+ years	42,670

Age Distribution (C 2020)
80+ years	9,904
70-79 years	18,034
60-69 years	32,457
50-59 years	34,489
40-49 years	31,405
30-39 years	33,667
20-29 years	30,879
10-19 years	34,843
0-9 years	31,722

Urbanization (C 2020)
Rural	36,437
Urban	220,963

»Race« (C 2020)
White	153,376
Black/African American	76,564
Indigenous	881
Asian	3,711
Pacific Islander	188
Some other	5,288
2 or more	17,392

Ethnicity (C 2020)
Hispanic or Latino	12,582
Other	244,818