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

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

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

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