Franklin County, Illinois

County in IL, US

By Neilsberg Research

Last updated May 1, 2026

Key Indicators

A quick look at key numbers

Population

37,323

Source: U.S. Census Bureau American Community Survey (ACS) 2020-2024 5-Year Estimates

Median Age

43.4

years ∙ half population younger than 43.4, half older

Diversity Index

11.3%

chance two random people differ in race and ethnicity

Nativity

1.2%

foreign-born population

98.8%Native

1.2% Foreign-born

Geographic Context

Location, size, and surroundings

About

Franklin County is a county in Illinois, United States.

Location

County in IL, US

Co-ordinates

DEC37.991852° N, 88.926321° W

DMS37° 59′ 30.67″ N, 88° 55′ 34.76″ W

Population Density & area

91.28/sq mi (35.24/km²)

Total Area

431.4 sq mi (1,117.5 km²)

Land Area

408.9 sq mi (1,059.1 km²) · 94.8%

Water Area

22.5 sq mi (58.4 km²) · 5.2%

Demographics & Living

Who lives here, how households are formed, and community composition

Population Composition

Key characteristics of the population

Sex Distribution

49.7% male

Male 49.7%

Female 50.3%

males per 100 females

Franklin County 98.7

Illinois 97.7

United States 98

Nativity

1.2%

foreign-born population

98.8%Native

1.2% Foreign-born

% Foreign-born

Franklin County 1.2%

Illinois 14.7%

United States 14.1%

Age Distribution

How the population is spread across age groups

Median Age

43.4

years ∙ half population younger than 43.4, half older

Franklin County

43.4

Illinois

United States

38.9

Dependency ratio

75.7

dependents per 100 working-age adults

Franklin County 75.7

Illinois 63.5

United States 64.4

AGE DISTRIBUTION

Distribution of age group

Median age

	Franklin County	Illinois	United States
Age Group
Children (Under 18)	22.1%	21.8%	22%
Working age (18-64)	56.9%	61.2%	60.8%
Senior (65+)	21%	17%	17.2%
Dependency ratio
Total dependency ratio	75.7	63.5	64.4
Child dependency ratio	38.8	35.7	36.1
Old-age dependency ratio	36.9	27.8	28.3

Racial & Ethnic Composition

Racial and ethnic makeup and how it compares

Race & Ethnicity

White

94.1%

Black

0.4%

Asian

0.4%

Hispanic

Other

3.1%

Note: White, Black, and Asian refer to individuals belonging to a single race and not of Hispanic origin. Hispanics may be of any race.

Diversity Index

11.3%

chance two random people differ in race and ethnicity

Franklin County 11.3%

Illinois 60.5%

United States 61.4%

Note: The Diversity Index (DI), based on the Blau Index, measures the probability that two randomly selected individuals differ in race and ethnicity. Values range from 0 (no diversity) to 1 (high diversity) and are shown as percentages.

RACIAL & ETHNIC COMPOSITION

Race & Ethnicity

Percentage of Franklin County population

	Franklin County	Illinois	United States
Hispanic or Latino	2%	18.8%	19.3%
Mexican	1.5%	14.4%	11.3%
Puerto Rican	0.1%	1.6%	1.8%
Cuban	0%	0.3%	0.8%
Other Hispanic / Latino	0.4%	2.5%	5.5%
Not Hispanic or Latino	98%	81.2%	80.7%
One race	95.2%	77.8%	76.4%
White	94.1%	58.1%	57.4%
Black or African American	0.4%	13.3%	11.9%
American Indian and Alaska Native	0.1%	0.1%	0.5%
Asian	0.4%	5.9%	5.9%
Native Hawaiian and Other Pacific Islander	0%	0%	0.2%
Some Other Race	0.2%	0.4%	0.6%
Two or more races (Multiracial)	2.8%	3.4%	4.3%

Household & Families Composition

Household size, type, and family structure

Household structure

62.5% family

Family 62.5%

Non family 37.5%

% family households

Franklin County 62.5%

Illinois 62.2%

United States 64.2%

Average household size

2.28

persons per household

Franklin County

2.28

Illinois

2.46

United States

2.53

Household & Family COMPOSITION

Households

Percentage of Franklin County population

	Franklin County	Illinois	United States
Total households	16,137	5,036,449	129,227,496
Average houshold size	2.28	2.46	2.53
Family households	10,091	3,130,978	82,990,528
Average family size	2.87	3.14	3.14
Married couple family	7,060	2,282,435	60,637,388
Other families	3,031	848,543	22,353,140
Male householder	906	248,521	6,572,819
Female householder	2,125	600,022	15,780,321
Non-family households	6,046	1,905,471	46,236,968
One-person households	5,317	1,569,881	37,140,836
Male householder	2,742	712,191	16,871,444
Senior (65+) living alone	1,216	210,051	5,225,110
Female householder	2,575	857,690	20,269,392
Senior (65+) living alone	1,493	417,870	10,089,070
Other living arrangements	729	335,590	9,096,132

Housing Profile

Housing stock, ownership, rentals, and cost burdens

Total housing units

18,462

housing units

Franklin County 18,462

Illinois 5,457,452

United States 143,775,355

Occupancy status

87.4% occupied

Occupied 87.4%

Vacant 12.6%

vacancy rate

Franklin County 12.6%

Illinois 7.7%

United States 10.1%

Housing Characteristics

How the housing supply is structured and used

Types of Housing unit

80.5%

Single family houses

80.5%

Apartments in multi-unit structures

9.1%

Mobile homes

10.3%

Boat, RV, van, etc

0.1%

Median Year Built

1964

Half of houses were built before 1964, and half after.

Historic ∙ 1939 or earlier

22.9%

Postwar & mid-century ∙ 1940 - 1969

34.5%

Late 20th century ∙ 1970 - 1999

28.5%

Modern ∙ 2000 or later

14.1%

Note: Median year built reflects occupied units only; distribution includes all units.

Housing Characteristics

Units, rooms & bedrooms

Physical characteristics of housing units

	Franklin County	Illinois	United States
Rooms per unit
Median rooms	5.5	5.6	5.5
1–3 rooms	8.6%	14.6%	15.1%
4–6 rooms	61.6%	50.9%	51.6%
7+ rooms	30%	34.6%	33.4%
Bedrooms
No bedroom / studio	1.2%	3.1%	2.9%
1 bedroom	8.5%	11.5%	10.9%
2 bedrooms	36.8%	27.7%	25%
3 bedrooms	43%	35.8%	38.7%
4+ bedrooms	10.5%	21.7%	22.4%
At a glance
Median year built	1964	1971	1981
Total housing units	18,462	5,457,452	143,775,355

Occupancy Profile

Who is inside and how they use it

Homeownership

74.1% owners

Renter-occupied 25.9%

Owner-occupied 74.1%

homeownership rate

Franklin County 74.1%

Illinois 67.1%

United States 65.2%

Average household size

2.3

Owner-occupied

2.24

Renter-occupied

owner-occupied average size

Franklin County 2.3

Illinois 2.62

United States 2.64

Housing Characteristics

Occupied unit characteristics

Tenure, crowding, and utilities

	Franklin County	Illinois	United States
Total occupied units	16,137	5,036,449	129,227,496
Year moved in
2020 or later	20.7%	23.3%	24.8%
2010 to 2019	34.5%	38.1%	39.6%
2000 to 2009	19.2%	17.3%	16.4%
1999 or earlier	25.6%	21.3%	19.1%
Occupants per room
1.00 or fewer	98.2%	97.5%	96.6%
1.01 to 1.50	1.3%	1.6%	2.2%
1.51 or more	0.5%	0.8%	1.2%
Vehicles availability
No vehicles	6.3%	11%	8.4%
1 vehicle	34%	35.7%	33.1%
2 vehicles	35.1%	35.1%	36.6%
3 or more vehicles	24.6%	18.3%	21.9%
House heating fuel used
Gas	48.1%	79.5%	51.4%
Electricity	49.1%	18.6%	41.3%
Solar	0.1%	0.1%	0.3%
Fuel oil, kerosene etc	0.1%	0.1%	3.9%
All other fuels	2.3%	0.8%	2%
No fuel used	0.4%	0.8%	1.2%
Selected characteristics
Lacking complete plumbing	0.4%	0.3%	0.4%
Lacking complete kitchen	1.2%	0.8%	0.8%
No telephone service available	1.7%	0.8%	0.9%

Housing Value

What owner-occupied units are worth

Median home value

$89,000

owner-occupied units

Median value(USD)

Franklin County

$89,000

Illinois

$263,300

United States

$332,700

Housing Cost Burden

22.5%

of homeowners with a mortgage are cost-burdened

% Cost-Burdened Households

Owners with a mortgage

22.5%

Owners without a mortgage

12.9%

Renters

52.1%

Note: Households spending 30% or more of their income on housing costs are considered cost-burdened.

Financial characteristics

Property value and housing costs

Tenure, crowding, and utilities

	Franklin County	Illinois	United States
Property value
Median Value	$89,000	$263,300	$332,700
Under $100,000	54.7%	13.7%	11.4%
$100,000 - $200,000	26.6%	21.5%	15.8%
$200,000 - $300,000	10.5%	22.3%	17.8%
$300,000 - $500,000	6%	27.7%	26.9%
$500,000 - $1,000,000	1.3%	12.1%	20.9%
$1,000,000 and more	0.9%	2.7%	7.1%
Owner-occupied households
With a mortgage	40.8%	60.8%	60.6%
Without a mortgage	59.2%	39.2%	39.4%
Median monthly owner costs
With a mortgage	$1,171	$1,987	$1,963
Without a mortgage	$463	$792	$638
Gross rent
Median rent	$803	$1,274	$1,413

Education Profile

How educated is the community and how education pays off

Adults with a college degree

15.8%

of adults 25+ with a bachelor's degree or higher

Franklin County 15.8%

Illinois 37.8%

United States 35.7%

Adults without a high school diploma

10.4%

of adults (25+) without a high school diploma

Franklin County 10.4%

Illinois 9.6%

United States 10.4%

School Enrollment

Who is enrolled in school and at what level

School enrollment

7,693

population (age 3+) enrolled in school

Nursery / Preschool

7.3%

K–12

76.8%

College / Undergraduate

12.7%

Graduate / Professional

3.2%

College-going rate (18-24 yr olds)

25.9%

of 18-24-year-olds in college or graduate school

Franklin County

25.9%

Illinois

41.4%

United States

40.9%

Enrollment & school type

Enrollment levels, college-going rate, and public vs private school split

Population 3+ currently enrolled in a school

	Franklin County	Illinois	United States
Total enrolled (age 3+)	7,693	3,051,569	80,089,790
Nursery / preschool	7.3%	6.3%	5.7%
K–12	76.8%	67.3%	67.6%
Kindergarten	6.1%	4.9%	5%
Elementary: Grades 1–4	19.5%	19.5%	19.8%
Elementary: Grades 5–8	24.8%	20.8%	21%
High School: Grades 9–12	26.5%	22.1%	21.7%
College or graduate school	15.8%	26.4%	26.7%
College, undergraduate	12.7%	19.8%	21%
Graduate, professional school	3.2%	6.6%	5.8%
College-going rate · 18-24 yr olds	25.9%	41.4%	40.9%
School type
Public school	87.7%	80.5%	82%
Private school	12.3%	19.5%	18%

Education Attainment by Level & Gender

What is the highest level of education completed among adults

Education attainment

26,433

population 25 years and over

Total adults (25+)

Less than 9th grade

3.2%

9th-12th, no diploma

7.2%

HS graduate

32.8%

Some college no degree

27.4%

Associates degree

13.7%

Bachelors degree

10.7%

Graduate or professional degree

5.1%

Attainment by gender

Male vs Female

Adults (25+) · Share within each education level

% male · % female

Less than 9th grade

59.1% · 40.9%

9th-12th, no diploma

49.8% · 50.2%

HS graduate

51.3% · 48.7%

Some college no degree

47.5% · 52.5%

Associates degree

47.4% · 52.6%

Bachelors degree

46.7% · 53.3%

Graduate or professional degree

36.9% · 63.1%

Educational Attainment Overview

Distribution and key education attainment rates for adults (25+)

Highest credential completed · adults 25+

	Franklin County	Illinois	United States
Population (25+)	26,433	8,767,004	230,807,303
Less than 9th grade	3.2%	4.6%	4.7%
9th–12th, no diploma	7.2%	5%	5.7%
High school diploma or GED	32.8%	25.1%	26%
Some college, no degree	27.4%	19.2%	19.1%
Associate's degree	13.7%	8.3%	8.8%
Bachelor's degree or higher	15.8%	37.8%	35.7%
Bachelor's degree	10.7%	22.6%	21.6%
Graduate or professional	5.1%	15.3%	14.1%
High School or higher	89.6%	90.5%	89.6%

Earnings by education level

percentage as applicable

Median Earnings

$42,394

Median earnings for adults 25+, by level

Less than HS graduate

$32,826

HS graduate

$38,877

Some college or associates

$41,886

Bachelors degree

$54,082

Graduate or professional degree

$67,961

Poverty Rate

9.7%

for ages 25+, with bachelors degree or higher

Less than HS graduate

33.6%

HS graduate

19.7%

Some college or associates

10.8%

Bachelors degree or higher

9.7%

Outcomes by Education Level

Earnings and poverty rates across education levels (25+)

Adults 25+

	Franklin County	Illinois	United States
Median earnings
Population 25+, with earnings	$42,394	$55,582	$52,696
Less than high school graduate	$32,826	$34,655	$32,485
High school graduate (includes equivalency)	$38,877	$40,965	$40,153
Some college or associate's degree	$41,886	$47,813	$47,260
Bachelor's degree	$54,082	$73,326	$70,044
Graduate or professional degree	$67,961	$91,623	$90,720
Poverty rates
Less than high school graduate	33.6%	21.6%	24.2%
High school graduate (includes equivalency)	19.7%	14.4%	14.4%
Some college or associate's degree	10.8%	9.9%	9.8%
Bachelor's degree or higher	9.7%	4.5%	4.5%

Insights for Franklin County, by topic

Income By year By race By age By gender

Population By year By race By age By gender

About Neilsberg Research

Neilsberg Research team are data scientists with expertise in processing, analysis and visualization of big data helping small businesses make right decisions.

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