St. Clair township Flag

St. Clair township

County Seat:
No
Area (mi²):
20.364
State:
Illinois

St. Clair township is located in St. Clair County, Illinois. St. Clair township has a 2026 population of 35,180. St. Clair township is currently declining at a rate of -0.54% annually and its population has decreased by -1.43% since the most recent census, which recorded a population of 35,691 in 2020.

The median household income in St. Clair township is $80,309 with a poverty rate of 11.73%. The median age in St. Clair township is 42.4 years: 41 years for males, and 43.5 years for females. For every 100 females there are 96.1 males.

35.2K
Total Population
1,728
Density (mi²)
-190 -0.54%
Growth

St. Clair township Population

St. Clair township Population

Data after 2023 is projected based on recent change

Year ↓
Population
Growth
Annual Change
202635,180-190-0.54%
202535,370-190-0.53%
202435,560-190-0.53%
202335,7503861.09%
202235,364-193-0.54%
202135,557-134-0.38%
202035,691-69-0.19%
201935,093-3-0.01%
201835,096-151-0.43%
201735,247-66-0.19%
201635,313-96-0.27%
201535,409-201-0.56%
201435,610-139-0.39%
201335,749-166-0.46%
201235,915-90-0.25%
201136,0055071.43%
201035,8601580.44%

Median Age

Overall: 42.4 years
Female: 43.5 years
Male: 41 years

St. Clair township Adults

There are 28,344 adults, (6,619 of whom are seniors) in St. Clair township.

Sex Ratio

Female: 18,159 (51%)
Male: 17,442 (49%)

Demographics

The racial composition of St. Clair township includes 65.53% White, 23.15% Black or African American, 3.14% Asian, and smaller percentages for other race, Native American and multiracial populations.

Population by Race

Race
Population ↓
Percentage (of total)
White23,32965.53%
Black or African American8,24323.15%
Two or more races2,0885.87%
Asian1,1193.14%
Other race6621.86%
Native American1600.45%
Race
Population ↓
Percentage (of total)
White2470.69%
Two or more races1290.36%
Other race930.26%
Black or African American500.14%
Native American440.12%
Asian220.06%
Race
Population ↓
Percentage (of total)
White23,08264.84%
Black or African American8,19323.01%
Two or more races1,9595.5%
Asian1,0973.08%
Other race5691.6%
Native American1160.33%

St. Clair township Marital Status

Economics and Income Statistics

St. Clair township 's average per capita income is $56,717. Household income levels show a median of $80,309. The poverty rate stands at 11.73%.

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$128,510-
Families$110,931$128,671
Households$80,309$101,289
Non Families$42,112$54,740

$56,717

Average Income

$80,309

Median Household Income

11.73%

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)