Marion County, Illinois

Marion County, Illinois, had an estimated population of 36,382 in 2025 across 1,483 km². The figures below come from the US Census Bureau's population estimates and the American Community Survey, each shown with its own vintage and its rank among Illinois's counties and nationally.

Population: 36,382; 2025 estimate
Area: 1,483 km²
Density: 25; per km²
Median income: $61,240; household, ACS 2024
Median age: 41.5; years, ACS 2024

How Illinois's counties spread

Amenities & Infrastructure

Indicator	Value	In Illinois	In the US
Households with Broadband2024	86.0%	68 / 102	1,796 / 3,144
Median Gross Rent2024	$794	61 / 102	2,143 / 3,137
Median Home Value2024	$103,000	88 / 102	2,887 / 3,139
Owner-Occupied Homes2024	74.7%	66 / 102	1,549 / 3,144
Vacant Homes2024	10.5%	53 / 102	2,108 / 3,144

Demography

Indicator	Value	In Illinois	In the US
Aged 65 and Over2024	20.2%	59 / 102	1,485 / 3,144
American Indian & Alaska Native2024	0.1%	18 / 102	1,566 / 3,144
Asian, non-Hispanic2024	0.7%	39 / 102	1,366 / 3,144
Average Household Size2024people	2.3	50 / 102	2,177 / 3,144
Black, non-Hispanic2024	2.9%	48 / 102	1,395 / 3,144
Foreign-Born2024	1.5%	55 / 102	2,291 / 3,144
Hispanic or Latino2024	2.2%	66 / 102	2,549 / 3,144
Median Age2024years	41.5	62 / 102	1,565 / 3,144
Sex Ratio2024per 1,000 males	1,032	21 / 102	794 / 3,144
Speak a Language Other Than English2024	2.5%	66 / 102	2,534 / 3,144
Under 182024	23.5%	13 / 102	848 / 3,144
Veterans2024	7.8%	39 / 102	1,179 / 3,144
White, non-Hispanic2024	89.1%	48 / 102	878 / 3,144

Economy

Indicator	Value	In Illinois	In the US
Below Poverty Line2024	15.4%	24 / 102	1,113 / 3,144
Households on SNAP2024	19.8%	8 / 102	418 / 3,144
Income Inequality2024index	0.434	48 / 102	1,987 / 3,144
Median Household Income2024	$61,240	78 / 102	1,961 / 3,143
Per Capita Income2024	$32,825	80 / 102	1,961 / 3,144
Unemployment Rate2024	5.9%	19 / 102	660 / 3,144

Education

Indicator	Value	In Illinois	In the US
Bachelor's Degree or Higher2024	16.8%	89 / 102	2,450 / 3,144
High School or Higher2024	90.7%	66 / 102	1,440 / 3,144

Health Coverage

Indicator	Value	In Illinois	In the US
No Health Insurance2024	6.4%	19 / 102	1,999 / 3,144
With a Disability2024	19.1%	20 / 102	772 / 3,144

Population & Density

Indicator	Value	In Illinois	In the US
Population2025	36,382	37 / 102	1,288 / 3,144
Population Density2025/km²	25	37 / 102	1,229 / 3,144

Work & Commute

Indicator	Value	In Illinois	In the US
Commute by Public Transit2024	0.2%	62 / 102	1,371 / 3,144
Households with No Vehicle2024	7.0%	32 / 102	797 / 3,144
Mean Commute Time2024minutes	21.1	70 / 102	2,246 / 3,143
Work from Home2024	4.8%	89 / 102	2,674 / 3,144

Other counties of Illinois

Compare Marion County against every other county on a map, add layers and run a scatter — open the atlas. Sources and vintages for every figure on this page are listed under datasets, or browse all 3,144 counties.