O'Fallon Flag

O'Fallon

County Seat:
No
Area (mi²):
35.11
State:
Illinois

O'Fallon is located in St. Clair County, Illinois. O'Fallon has a 2025 population of 25,805. O'Fallon is currently declining at a rate of -0.43% annually and its population has decreased by -2.14% since the most recent census, which recorded a population of 26,370 in 2020.

The average household income in O'Fallon is $123,124 with a poverty rate of 5.75%.The median age in O'Fallon is 38.3 years: 38 years for males, and 38.7 years for females.

25.8K
Total Population
735
Density (mi²)
-112 -0.43%
Growth

O'Fallon Population

O'Fallon Population

Data after 2023 is projected based on recent change

Demographics

The racial composition of O'Fallon includes 71.78% White, 14.12% Black or African American, and smaller percentages for Asian, other race, Native American and multiracial populations.

Population by Race

White (71.8%)

Black or African American (14.1%)

Two or more races (10.2%)

Asian (2.5%)

Other race (1.3%)

Native American (0.1%)

Race
Population
Percentage (of total)
White18,84771.78%
Black or African American3,70714.12%
Two or more races2,68310.22%
Asian6532.49%
Other race3441.31%
Native American230.09%

O'Fallon Marital Status

OverallMalesFemales0%10%20%30%40%50%60%70%80%90%100%

Married

Widowed

Divorced

Separated

Never Married

Economics and Income Statistics

O'Fallon's average per capita income is $60,027. Household income levels show a median of $92,328. The poverty rate stands at 5.75%.

Families: A family includes the owner or renter of the home along with everyone related to them - whether through birth, marriage, or adoption. This includes relatives like spouses, children, parents, siblings, grandparents, and any other family members.
Households: A household includes all the people who occupy a housing unit (such as a house or apartment) as their usual place of residence.
Non Families: A nonfamily household is either someone living alone or when the owner/renter lives with people they aren't related to, like roommates.
Name
Median
Mean
Married Families$140,604-
Families$122,136$146,118
Households$92,328$123,124
Non Families$51,081$59,076

$60,027

Average Income

$92,328

Median Household Income

5.75%

Poverty Rate

Nearby Cities

Sources

  1. US Census State Population Estimates - Most recent state estimates from the Census Bureau's Population Estimates Program
  2. US Census County Population Estimates - Most recent county estimates from the Census Bureau's Population Estimates Program
  3. American Community Survey (2009 - 2013)
  4. Census QuickFacts
  5. Historical Populations of States and Counties (1790 - 1990)