Sangamon County, Illinois

County in IL, US

By Neilsberg Research

Last updated May 1, 2026

Key Indicators

A quick look at key numbers

Population

194,947

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

Median Age

years ∙ half population younger than 41, half older

Diversity Index

38.4%

chance two random people differ in race and ethnicity

Nativity

3.6%

foreign-born population

96.4%Native

3.6% Foreign-born

Geographic Context

Location, size, and surroundings

About

Sangamon County is a county in Illinois, United States.

Location

County in IL, US

Co-ordinates

DEC39.756886° N, 89.662435° W

DMS39° 45′ 24.79″ N, 89° 39′ 44.77″ W

Population Density & area

224.5/sq mi (86.69/km²)

Total Area

877 sq mi (2,271.4 km²)

Land Area

868.2 sq mi (2,248.7 km²) · 99%

Water Area

8.8 sq mi (22.7 km²) · 1%

Demographics & Living

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

Population Composition

Key characteristics of the population

Sex Distribution

48.3% male

Male 48.3%

Female 51.7%

males per 100 females

Sangamon County 93.3

Illinois 97.7

United States 98

Nativity

3.6%

foreign-born population

96.4%Native

3.6% Foreign-born

% Foreign-born

Sangamon County 3.6%

Illinois 14.7%

United States 14.1%

Age Distribution

How the population is spread across age groups

Median Age

years ∙ half population younger than 41, half older

Sangamon County

Illinois

United States

38.9

Dependency ratio

70.3

dependents per 100 working-age adults

Sangamon County 70.3

Illinois 63.5

United States 64.4

AGE DISTRIBUTION

Distribution of age group

Median age

	Sangamon County	Illinois	United States
Age Group
Children (Under 18)	21.9%	21.8%	22%
Working age (18-64)	58.7%	61.2%	60.8%
Senior (65+)	19.4%	17%	17.2%
Dependency ratio
Total dependency ratio	70.3	63.5	64.4
Child dependency ratio	37.3	35.7	36.1
Old-age dependency ratio	33.1	27.8	28.3

Racial & Ethnic Composition

Racial and ethnic makeup and how it compares

Race & Ethnicity

White

77.3%

Black

12.5%

Asian

2.3%

Hispanic

2.9%

Other

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

38.4%

chance two random people differ in race and ethnicity

Sangamon County 38.4%

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 Sangamon County population

	Sangamon County	Illinois	United States
Hispanic or Latino	2.9%	18.8%	19.3%
Mexican	1.3%	14.4%	11.3%
Puerto Rican	0.5%	1.6%	1.8%
Cuban	0.1%	0.3%	0.8%
Other Hispanic / Latino	1.1%	2.5%	5.5%
Not Hispanic or Latino	97.1%	81.2%	80.7%
One race	92.8%	77.8%	76.4%
White	77.3%	58.1%	57.4%
Black or African American	12.5%	13.3%	11.9%
American Indian and Alaska Native	0.1%	0.1%	0.5%
Asian	2.3%	5.9%	5.9%
Native Hawaiian and Other Pacific Islander	0%	0%	0.2%
Some Other Race	0.5%	0.4%	0.6%
Two or more races (Multiracial)	4.3%	3.4%	4.3%

Household & Families Composition

Household size, type, and family structure

Household structure

57.3% family

Family 57.3%

Non family 42.7%

% family households

Sangamon County 57.3%

Illinois 62.2%

United States 64.2%

Average household size

2.25

persons per household

Sangamon County

2.25

Illinois

2.46

United States

2.53

Household & Family COMPOSITION

Households

Percentage of Sangamon County population

	Sangamon County	Illinois	United States
Total households	84,762	5,036,449	129,227,496
Average houshold size	2.25	2.46	2.53
Family households	48,532	3,130,978	82,990,528
Average family size	2.97	3.14	3.14
Married couple family	35,406	2,282,435	60,637,388
Other families	13,126	848,543	22,353,140
Male householder	3,509	248,521	6,572,819
Female householder	9,617	600,022	15,780,321
Non-family households	36,230	1,905,471	46,236,968
One-person households	30,883	1,569,881	37,140,836
Male householder	13,475	712,191	16,871,444
Senior (65+) living alone	3,916	210,051	5,225,110
Female householder	17,408	857,690	20,269,392
Senior (65+) living alone	8,691	417,870	10,089,070
Other living arrangements	5,347	335,590	9,096,132

Housing Profile

Housing stock, ownership, rentals, and cost burdens

Total housing units

93,382

housing units

Sangamon County 93,382

Illinois 5,457,452

United States 143,775,355

Occupancy status

90.8% occupied

Occupied 90.8%

Vacant 9.2%

vacancy rate

Sangamon County 9.2%

Illinois 7.7%

United States 10.1%

Housing Characteristics

How the housing supply is structured and used

Types of Housing unit

79%

Single family houses

79%

Apartments in multi-unit structures

16.9%

Mobile homes

3.9%

Boat, RV, van, etc

Median Year Built

1974

Half of houses were built before 1974, and half after.

Historic ∙ 1939 or earlier

15.5%

Postwar & mid-century ∙ 1940 - 1969

27.8%

Late 20th century ∙ 1970 - 1999

40.8%

Modern ∙ 2000 or later

15.8%

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

Housing Characteristics

Units, rooms & bedrooms

Physical characteristics of housing units

	Sangamon County	Illinois	United States
Rooms per unit
Median rooms	5.6	5.6	5.5
1–3 rooms	11.5%	14.6%	15.1%
4–6 rooms	53.3%	50.9%	51.6%
7+ rooms	35.2%	34.6%	33.4%
Bedrooms
No bedroom / studio	0.9%	3.1%	2.9%
1 bedroom	9.5%	11.5%	10.9%
2 bedrooms	28.8%	27.7%	25%
3 bedrooms	41.2%	35.8%	38.7%
4+ bedrooms	19.5%	21.7%	22.4%
At a glance
Median year built	1974	1971	1981
Total housing units	93,382	5,457,452	143,775,355

Occupancy Profile

Who is inside and how they use it

Homeownership

71.3% owners

Renter-occupied 28.7%

Owner-occupied 71.3%

homeownership rate

Sangamon County 71.3%

Illinois 67.1%

United States 65.2%

Average household size

2.35

Owner-occupied

2.01

Renter-occupied

owner-occupied average size

Sangamon County 2.35

Illinois 2.62

United States 2.64

Housing Characteristics

Occupied unit characteristics

Tenure, crowding, and utilities

	Sangamon County	Illinois	United States
Total occupied units	84,762	5,036,449	129,227,496
Year moved in
2020 or later	23.5%	23.3%	24.8%
2010 to 2019	38.8%	38.1%	39.6%
2000 to 2009	18.2%	17.3%	16.4%
1999 or earlier	19.4%	21.3%	19.1%
Occupants per room
1.00 or fewer	98.5%	97.5%	96.6%
1.01 to 1.50	1.2%	1.6%	2.2%
1.51 or more	0.3%	0.8%	1.2%
Vehicles availability
No vehicles	7.6%	11%	8.4%
1 vehicle	36.8%	35.7%	33.1%
2 vehicles	38%	35.1%	36.6%
3 or more vehicles	17.6%	18.3%	21.9%
House heating fuel used
Gas	77.7%	79.5%	51.4%
Electricity	21.3%	18.6%	41.3%
Solar	0%	0.1%	0.3%
Fuel oil, kerosene etc	0.1%	0.1%	3.9%
All other fuels	0.5%	0.8%	2%
No fuel used	0.3%	0.8%	1.2%
Selected characteristics
Lacking complete plumbing	0.2%	0.3%	0.4%
Lacking complete kitchen	0.5%	0.8%	0.8%
No telephone service available	0.9%	0.8%	0.9%

Housing Value

What owner-occupied units are worth

Median home value

$176,300

owner-occupied units

Median value(USD)

Sangamon County

$176,300

Illinois

$263,300

United States

$332,700

Housing Cost Burden

20.3%

of homeowners with a mortgage are cost-burdened

% Cost-Burdened Households

Owners with a mortgage

20.3%

Owners without a mortgage

10.2%

Renters

45.8%

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

	Sangamon County	Illinois	United States
Property value
Median Value	$176,300	$263,300	$332,700
Under $100,000	21.2%	13.7%	11.4%
$100,000 - $200,000	35.2%	21.5%	15.8%
$200,000 - $300,000	22.7%	22.3%	17.8%
$300,000 - $500,000	16.1%	27.7%	26.9%
$500,000 - $1,000,000	4.1%	12.1%	20.9%
$1,000,000 and more	0.7%	2.7%	7.1%
Owner-occupied households
With a mortgage	59.4%	60.8%	60.6%
Without a mortgage	40.6%	39.2%	39.4%
Median monthly owner costs
With a mortgage	$1,494	$1,987	$1,963
Without a mortgage	$651	$792	$638
Gross rent
Median rent	$983	$1,274	$1,413

Education Profile

How educated is the community and how education pays off

Adults with a college degree

36.6%

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

Sangamon County 36.6%

Illinois 37.8%

United States 35.7%

Adults without a high school diploma

5.8%

of adults (25+) without a high school diploma

Sangamon County 5.8%

Illinois 9.6%

United States 10.4%

School Enrollment

Who is enrolled in school and at what level

School enrollment

43,260

population (age 3+) enrolled in school

Nursery / Preschool

K–12

72.8%

College / Undergraduate

14.8%

Graduate / Professional

5.4%

College-going rate (18-24 yr olds)

32%

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

Sangamon County

32%

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

	Sangamon County	Illinois	United States
Total enrolled (age 3+)	43,260	3,051,569	80,089,790
Nursery / preschool	7%	6.3%	5.7%
K–12	72.8%	67.3%	67.6%
Kindergarten	5.1%	4.9%	5%
Elementary: Grades 1–4	21.8%	19.5%	19.8%
Elementary: Grades 5–8	22.4%	20.8%	21%
High School: Grades 9–12	23.5%	22.1%	21.7%
College or graduate school	20.1%	26.4%	26.7%
College, undergraduate	14.8%	19.8%	21%
Graduate, professional school	5.4%	6.6%	5.8%
College-going rate · 18-24 yr olds	32%	41.4%	40.9%
School type
Public school	79.9%	80.5%	82%
Private school	20.1%	19.5%	18%

Education Attainment by Level & Gender

What is the highest level of education completed among adults

Education attainment

136,639

population 25 years and over

Total adults (25+)

Less than 9th grade

1.5%

9th-12th, no diploma

4.3%

HS graduate

28.1%

Some college no degree

20.5%

Associates degree

8.9%

Bachelors degree

21.8%

Graduate or professional degree

14.8%

Attainment by gender

Male vs Female

Adults (25+) · Share within each education level

% male · % female

Less than 9th grade

56.1% · 43.9%

9th-12th, no diploma

52.4% · 47.6%

HS graduate

48.5% · 51.5%

Some college no degree

47.8% · 52.2%

Associates degree

44.9% · 55.1%

Bachelors degree

44.9% · 55.1%

Graduate or professional degree

45.2% · 54.8%

Educational Attainment Overview

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

Highest credential completed · adults 25+

	Sangamon County	Illinois	United States
Population (25+)	136,639	8,767,004	230,807,303
Less than 9th grade	1.5%	4.6%	4.7%
9th–12th, no diploma	4.3%	5%	5.7%
High school diploma or GED	28.1%	25.1%	26%
Some college, no degree	20.5%	19.2%	19.1%
Associate's degree	8.9%	8.3%	8.8%
Bachelor's degree or higher	36.6%	37.8%	35.7%
Bachelor's degree	21.8%	22.6%	21.6%
Graduate or professional	14.8%	15.3%	14.1%
High School or higher	94.1%	90.5%	89.6%

Earnings by education level

percentage as applicable

Median Earnings

$54,994

Median earnings for adults 25+, by level

Less than HS graduate

$30,897

HS graduate

$39,258

Some college or associates

$49,027

Bachelors degree

$66,662

Graduate or professional degree

$83,598

Poverty Rate

3.8%

for ages 25+, with bachelors degree or higher

Less than HS graduate

34.5%

HS graduate

17.4%

Some college or associates

9.2%

Bachelors degree or higher

3.8%

Outcomes by Education Level

Earnings and poverty rates across education levels (25+)

Adults 25+

	Sangamon County	Illinois	United States
Median earnings
Population 25+, with earnings	$54,994	$55,582	$52,696
Less than high school graduate	$30,897	$34,655	$32,485
High school graduate (includes equivalency)	$39,258	$40,965	$40,153
Some college or associate's degree	$49,027	$47,813	$47,260
Bachelor's degree	$66,662	$73,326	$70,044
Graduate or professional degree	$83,598	$91,623	$90,720
Poverty rates
Less than high school graduate	34.5%	21.6%	24.2%
High school graduate (includes equivalency)	17.4%	14.4%	14.4%
Some college or associate's degree	9.2%	9.9%	9.8%
Bachelor's degree or higher	3.8%	4.5%	4.5%

Insights for Sangamon 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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