Marshall County, Illinois Population 2026
Updated April 2026 · US Census ACS 2023 5-Year Estimates · 85th-largest in Illinois
The population of Marshall County, Illinois is 11,715 as of the 2023 American Community Survey, making it the 85th-largest county in Illinois. The median household income is $69,818, the median home value is $137,800, and the median age is 45.9.
The population of Marshall County has declined 8.6% since 2010 (12,637 → 11,552), a -0.64% annualized rate.
11,715
Population
-0.64%
Annual growth
30
People / sq mi
$69,818
Median Income
$137,800
Median Home Value
Marshall County covers 387 sq mi of land at 30.3 people per square mile.
About Marshall County, IL
Marshall County is distinguished by its share of foreign-born residents, 12.2% of the population. Marshall County is a county in Illinois with a population of 11,715.
The typical household here earns about $69,818, below the US median of $78,538. About 8.3% of residents live below the federal poverty level, below the national 12.4%. Homes carry a median value of $137,800, with typical rent around $767.
Roughly 18.7% of adults have a bachelor’s, below the national 35.0%. Just 5.8% of workers are home-based, below the national 14.0%, and the average commute runs about 28 minutes each way.
Marshall County Population History (2010-2024)
The county of Marshall County had a population of 12,637 in 2010 and 11,552 in 2024, a -8.6% growth over 14 years. The peak was 12,637 in 2010. Average annual growth rate: -0.63%.
11,552
Population (2024)
12,637
Population (2010)
12,637
Peak (2010)
-0.63%
Avg Annual Growth
| Year | Population |
|---|---|
| 2010 | 12,637 |
| 2011 | 12,488 |
| 2012 | 12,261 |
| 2013 | 12,129 |
| 2014 | 11,966 |
| 2015 | 11,925 |
| 2016 | 11,887 |
| 2017 | 11,667 |
| 2018 | 11,485 |
| 2019 | 11,463 |
| 2020 | 11,710 |
| 2021 | 11,665 |
| 2022 | 11,657 |
| 2023 | 11,650 |
| 2024 | 11,552 |
Race & Ethnicity
| White | 93.7% |
| Black or African American | 0.4% |
| Asian | 0.0% |
| Hispanic or Latino (any race) | 0.6% |
| Two or More Races | 0.0% |
Age & Sex
45.9
Median Age
49.7%
Female
50.3%
Male
23.6%
Age 65+
Age Distribution
Children (under 15): 17.6% · Seniors (65+): 23.6%
Income & Poverty
| Median household income | $69,818$-11,884 vs state |
| Mean household income | $83,438 |
| Per-capita income | $36,065 |
| Poverty rate | 8.3%+0.1% vs state |
| Unemployment rate | 2.6% |
| Employment-to-population | 53.4% |
Top Industries by Employment
The largest employment sector in Marshall County is professional & business services, accounting for 20.8% of workers.
How residents commute
0.0%
Drive alone
1.2%
Carpool
87.2%
Public transit
5.8%
Work from home
27.9 min
Avg commute
Housing
$137,800$-112,700 vs state
Median home value
$767
Median rent
79.7%
Homeownership rate
5,824
Total housing units
85.2%
Occupied
14.8%
Vacant
20.3%
Renter-occupied
Social & access
96.4%
With health insurance
91.0%
With broadband internet
12.2%
Foreign-born
9.3%
Veterans (18+)
15.6%
With a disability
97.1%
Speak language other than English at home
Education
91.0%
High School+
18.7%
Bachelor's+
Largest cities in Illinois
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County rankings
Frequently Asked Questions
Marshall County, Illinois has a population of 11,715 according to the US Census Bureau's 2023 American Community Survey 5-year estimates, making it the 85th-largest county in Illinois. Population density is 30 people per square mile.
The population of Marshall County has declined 8.6% since 2010 (12,637 → 11,552), a -0.64% annualized rate.
The median household income in Marshall County, Illinois is $69,818, with mean (average) household income of $83,438 and per-capita income of $36,065. 8.3% of residents live below the federal poverty level.
In Marshall County, the largest racial and ethnic groups are White (93.7%), Hispanic or Latino (0.6%), Black or African American (0.4%). Figures are from the US Census Bureau's 2023 ACS 5-year estimates and reflect self-reported responses.
The median age in Marshall County, Illinois is 45.9 years. Residents are 49.7% female and 50.3% male.
The median home value in Marshall County is $137,800 and median monthly rent is $767. 79.7% of occupied housing units are owner-occupied. The county has 5,824 total housing units, 14.8% of which are vacant.
The largest employment sector in Marshall County, Illinois is professional, scientific, and management services, employing 20.8% of workers. The unemployment rate is 2.6%.
Chicago is among the largest cities associated with Marshall County, Illinois, with a population of 2,707,648.
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Population, race, income, age, and trends across Illinois
Data from the American Community Survey (ACS) 5-Year estimates.
Source: U.S. Census Bureau ACS, 2026.