Editing O'Fallon, Illinois (section)

==Demographics==
{{US Census population
|1870= 1117
|1880= 921
|1890= 865
|1900= 1267
|1910= 2018
|1920= 2379
|1930= 2373
|1940= 2407
|1950= 3022
|1960= 4018
|1970= 7268
|1980= 12173
|1990= 16073
|2000= 21910
|2010= 28281
|2020= 32289
|align-fn=center
|footnote=U.S. Decennial Census<ref>{{cite web|url=https://www.census.gov/programs-surveys/decennial-census.html|title=Census of Population and Housing|author=United States Census Bureau|author-link=United States Census Bureau|access-date=May 13, 2015}}</ref><br />2018 Estimate<ref name="2018 Pop Estimate">{{cite web|title=Population Estimates|url=https://census.gov/data/tables/2018/demo/popest/total-cities-and-towns.html|publisher=[[United States Census Bureau]]|access-date=June 8, 2018}}</ref>
}}

As of the [[census]]<ref>{{Cite web |title=Explore Census Data |url=https://data.census.gov/profile/O'Fallon_city,_Illinois?g=160XX00US1755249 |access-date=2024-01-23 |website=data.census.gov}}</ref> of 2020, there were 32,289 people, 12,093 households, and 7,114 families living in the city. The population density was 2,959/sq mi (1,142/km<sup>2</sup>). There were 13,225 housing units at an average density of 1,158/sq mi (447/km<sup>2</sup>). The [[Race and ethnicity in the United States Census#2010 census|racial makeup]] of the city was 70.59% White, 16.38% African American, 0.22% Native American, 2.75% Asian, 0.10% Pacific Islander, 1.44% from other races, and 8.52% from two or more races. Hispanic or Latino of any race were 4.49% of the population.

Of the 12,093 households, 39.5% had children under the age of 18 living with them, 58.8% were married couples living together, 23.8% had a female householder with no spouse/partner present, and 13.3% had a male householder with no spouse/partner present. 23.1% of households were made up of individuals and 51.9% were one person aged 65 or older. The average household size was 2.65 and the average family size was 3.10.

The city's age distribution consisted of 28.2% under the age of 18, 6.4% from 18 to 24, 37.6% from 15 to 44, 12.3% from 45 to 64, and 15.5% 65 or older. The median age was 37.3 years. For every 100 females, there were 96.1 males.

The median household income was $102,560 and the median family income was $123,695. The per capita income for the city was $51,826. About 4.2% of families and 3.3% of the population were below the [[poverty line]], including 4.5% of those under age 18 and 3.1% of those age 65 or over.