Jefferson County Flag

Jefferson County

State:
Illinois
County Seat:
Mount Vernon

Jefferson County's estimated 2025 population is 36,122 with a growth rate of -0.27% in the past year according to the most recent United States census data. Jefferson County is the 38th largest county in Illinois. The 2010 population was 38,757 and has seen a growth of -6.8% since that time.

36,122
Total Population
63
Population Density (mi²)
38
Population Rank (State)
-99 -0.27%
Annual Population Growth

Jefferson County Population

Jefferson County Population

Data after 2023 is projected based on recent change

Demographics

The racial composition of Jefferson County includes 84.88% White, 6.51% Black or African American, and smaller percentages for Asian, other race, Native American, Native Hawaiian or Pacific Islander and multiracial populations.

Population by Race

White

Two or more races

Black or African American

Asian

Other race

Native American

Native Hawaiian or Pacific Islander

Race
Population
Percentage (of total)
White31,24184.88%
Two or more races2,4716.71%
Black or African American2,3986.51%
Asian3691%
Other race2450.67%
Native American760.21%
Native Hawaiian or Pacific Islander80.02%

Jefferson County Marital Status

Married

Widowed

Divorced

Separated

Never Married

Economics and Income Statistics

Jefferson County's average per capita income is $42,376. Household income levels show a median of $61,102. The poverty rate stands at 14.16%.

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$90,380$106,165
Families$74,499$90,351
Households$61,102$77,553
Non Families$34,689$48,822

$42,376

Average Income

$61,102

Median Household Income

14.16%

Poverty Rate