Buffalo, IL

Village in Sangamon County, IL, US

By Neilsberg Research

Last updated May 1, 2026

Key Indicators

A quick look at key numbers

Population

482

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

Median Age

45.9

years ∙ half population younger than 45.9, half older

Diversity Index

22.9%

chance two random people differ in race and ethnicity

Nativity

6.6%

foreign-born population

93.4%Native

6.6% Foreign-born

Geographic Context

Location, size, and surroundings

About

Buffalo is a village within Sangamon County, Illinois, United States.

Location

Village in Sangamon County, IL, US

Co-ordinates

DEC39.849911° N, 89.409125° W

DMS39° 50′ 59.68″ N, 89° 24′ 32.85″ W

Population Density & area

1,397/sq mi (539.8/km²)

Total Area

0.345 sq mi (0.893 km²)

Land Area

0.345 sq mi (0.893 km²) · 100%

Water Area

0 sq mi (0 km²) · 0%

Demographics & Living

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

Population Composition

Key characteristics of the population

Sex Distribution

47.9% male

Male 47.9%

Female 52.1%

males per 100 females

Buffalo 92

Sangamon County 93.3

Illinois 97.7

Nativity

6.6%

foreign-born population

93.4%Native

6.6% Foreign-born

% Foreign-born

Buffalo 6.6%

Sangamon County 3.6%

Illinois 14.7%

Age Distribution

How the population is spread across age groups

Median Age

45.9

years ∙ half population younger than 45.9, half older

Buffalo

45.9

Sangamon County

Illinois

Dependency ratio

86.1

dependents per 100 working-age adults

Buffalo 86.1

Sangamon County 70.3

Illinois 63.5

AGE DISTRIBUTION

Distribution of age group

Median age

	Buffalo	Sangamon County	Illinois
Age Group
Children (Under 18)	23%	21.9%	21.8%
Working age (18-64)	53.8%	58.7%	61.2%
Senior (65+)	23.2%	19.4%	17%
Dependency ratio
Total dependency ratio	86.1	70.3	63.5
Child dependency ratio	42.9	37.3	35.7
Old-age dependency ratio	43.2	33.1	27.8

Racial & Ethnic Composition

Racial and ethnic makeup and how it compares

Race & Ethnicity

White

87.1%

Black

Asian

0.2%

Hispanic

1.5%

Other

11.2%

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

22.9%

chance two random people differ in race and ethnicity

Buffalo 22.9%

Sangamon County 38.4%

Illinois 60.5%

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 Buffalo population

	Buffalo	Sangamon County	Illinois
Hispanic or Latino	1.5%	2.9%	18.8%
Mexican	1.5%	1.3%	14.4%
Puerto Rican	0%	0.5%	1.6%
Cuban	0%	0.1%	0.3%
Other Hispanic / Latino	0%	1.1%	2.5%
Not Hispanic or Latino	98.5%	97.1%	81.2%
One race	87.3%	92.8%	77.8%
White	87.1%	77.3%	58.1%
Black or African American	0%	12.5%	13.3%
American Indian and Alaska Native	0%	0.1%	0.1%
Asian	0.2%	2.3%	5.9%
Native Hawaiian and Other Pacific Islander	0%	0%	0%
Some Other Race	0%	0.5%	0.4%
Two or more races (Multiracial)	11.2%	4.3%	3.4%

Household & Families Composition

Household size, type, and family structure

Household structure

66.5% family

Family 66.5%

Non family 33.5%

% family households

Buffalo 66.5%

Sangamon County 57.3%

Illinois 62.2%

Average household size

2.45

persons per household

Buffalo

2.45

Sangamon County

2.25

Illinois

2.46

Household & Family COMPOSITION

Households

Percentage of Buffalo population

	Buffalo	Sangamon County	Illinois
Total households	197	84,762	5,036,449
Average houshold size	2.45	2.25	2.46
Family households	131	48,532	3,130,978
Average family size	3.05	2.97	3.14
Married couple family	90	35,406	2,282,435
Other families	41	13,126	848,543
Male householder	3	3,509	248,521
Female householder	38	9,617	600,022
Non-family households	66	36,230	1,905,471
One-person households	61	30,883	1,569,881
Male householder	26	13,475	712,191
Senior (65+) living alone	13	3,916	210,051
Female householder	35	17,408	857,690
Senior (65+) living alone	18	8,691	417,870
Other living arrangements	5	5,347	335,590

Housing Profile

Housing stock, ownership, rentals, and cost burdens

Total housing units

219

housing units

Buffalo 219

Sangamon County 93,382

Illinois 5,457,452

Occupancy status

90% occupied

Occupied 90%

Vacant 10%

vacancy rate

Buffalo 10%

Sangamon County 9.2%

Illinois 7.7%

Housing Characteristics

How the housing supply is structured and used

Types of Housing unit

70.8%

Single family houses

70.8%

Apartments in multi-unit structures

14.7%

Mobile homes

14.6%

Boat, RV, van, etc

Median Year Built

1964

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

Historic ∙ 1939 or earlier

17.8%

Postwar & mid-century ∙ 1940 - 1969

38.3%

Late 20th century ∙ 1970 - 1999

40.3%

Modern ∙ 2000 or later

3.6%

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

Housing Characteristics

Units, rooms & bedrooms

Physical characteristics of housing units

	Buffalo	Sangamon County	Illinois
Rooms per unit
Median rooms	5.1	5.6	5.6
1–3 rooms	29.2%	11.5%	14.6%
4–6 rooms	39.3%	53.3%	50.9%
7+ rooms	31.4%	35.2%	34.6%
Bedrooms
No bedroom / studio	0%	0.9%	3.1%
1 bedroom	19.6%	9.5%	11.5%
2 bedrooms	30.1%	28.8%	27.7%
3 bedrooms	36.5%	41.2%	35.8%
4+ bedrooms	13.7%	19.5%	21.7%
At a glance
Median year built	1964	1974	1971
Total housing units	219	93,382	5,457,452

Occupancy Profile

Who is inside and how they use it

Homeownership

69.5% owners

Renter-occupied 30.5%

Owner-occupied 69.5%

homeownership rate

Buffalo 69.5%

Sangamon County 71.3%

Illinois 67.1%

Average household size

2.85

Owner-occupied

1.53

Renter-occupied

owner-occupied average size

Buffalo 2.85

Sangamon County 2.35

Illinois 2.62

Housing Characteristics

Occupied unit characteristics

Tenure, crowding, and utilities

	Buffalo	Sangamon County	Illinois
Total occupied units	197	84,762	5,036,449
Year moved in
2020 or later	21.8%	23.5%	23.3%
2010 to 2019	39.6%	38.8%	38.1%
2000 to 2009	16.8%	18.2%	17.3%
1999 or earlier	21.8%	19.4%	21.3%
Occupants per room
1.00 or fewer	99.5%	98.5%	97.5%
1.01 to 1.50	0.5%	1.2%	1.6%
1.51 or more	0%	0.3%	0.8%
Vehicles availability
No vehicles	3.6%	7.6%	11%
1 vehicle	39.6%	36.8%	35.7%
2 vehicles	33%	38%	35.1%
3 or more vehicles	23.9%	17.6%	18.3%
House heating fuel used
Gas	78.7%	77.7%	79.5%
Electricity	21.3%	21.3%	18.6%
Solar	0%	0%	0.1%
Fuel oil, kerosene etc	0%	0.1%	0.1%
All other fuels	0%	0.5%	0.8%
No fuel used	0%	0.3%	0.8%
Selected characteristics
Lacking complete plumbing	0%	0.2%	0.3%
Lacking complete kitchen	0.5%	0.5%	0.8%
No telephone service available	0%	0.9%	0.8%

Housing Value

What owner-occupied units are worth

Median home value

$112,100

owner-occupied units

Median value(USD)

Buffalo

$112,100

Sangamon County

$176,300

Illinois

$263,300

Housing Cost Burden

30.5%

of homeowners with a mortgage are cost-burdened

% Cost-Burdened Households

Owners with a mortgage

30.5%

Owners without a mortgage

19.1%

Renters

65.3%

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

	Buffalo	Sangamon County	Illinois
Property value
Median Value	$112,100	$176,300	$263,300
Under $100,000	39.4%	21.2%	13.7%
$100,000 - $200,000	50.3%	35.2%	21.5%
$200,000 - $300,000	9.5%	22.7%	22.3%
$300,000 - $500,000	0.7%	16.1%	27.7%
$500,000 - $1,000,000	0%	4.1%	12.1%
$1,000,000 and more	0%	0.7%	2.7%
Owner-occupied households
With a mortgage	69.3%	59.4%	60.8%
Without a mortgage	30.7%	40.6%	39.2%
Median monthly owner costs
With a mortgage	$1,325	$1,494	$1,987
Without a mortgage	$550	$651	$792
Gross rent
Median rent	$533	$983	$1,274

Education Profile

How educated is the community and how education pays off

Adults with a college degree

25.6%

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

Buffalo 25.6%

Sangamon County 36.6%

Illinois 37.8%

Adults without a high school diploma

10.5%

of adults (25+) without a high school diploma

Buffalo 10.5%

Sangamon County 5.8%

Illinois 9.6%

School Enrollment

Who is enrolled in school and at what level

School enrollment

118

population (age 3+) enrolled in school

Nursery / Preschool

6.8%

K–12

78%

College / Undergraduate

11%

Graduate / Professional

4.2%

College-going rate (18-24 yr olds)

40.7%

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

Buffalo

40.7%

Sangamon County

32%

Illinois

41.4%

Enrollment & school type

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

Population 3+ currently enrolled in a school

	Buffalo	Sangamon County	Illinois
Total enrolled (age 3+)	118	43,260	3,051,569
Nursery / preschool	6.8%	7%	6.3%
K–12	78%	72.8%	67.3%
Kindergarten	3.4%	5.1%	4.9%
Elementary: Grades 1–4	20.3%	21.8%	19.5%
Elementary: Grades 5–8	22%	22.4%	20.8%
High School: Grades 9–12	32.2%	23.5%	22.1%
College or graduate school	15.3%	20.1%	26.4%
College, undergraduate	11%	14.8%	19.8%
Graduate, professional school	4.2%	5.4%	6.6%
College-going rate · 18-24 yr olds	40.7%	32%	41.4%
School type
Public school	99.2%	79.9%	80.5%
Private school	0.8%	20.1%	19.5%

Education Attainment by Level & Gender

What is the highest level of education completed among adults

Education attainment

344

population 25 years and over

Total adults (25+)

Less than 9th grade

1.2%

9th-12th, no diploma

9.3%

HS graduate

40.1%

Some college no degree

16.3%

Associates degree

7.6%

Bachelors degree

14.5%

Graduate or professional degree

11%

Attainment by gender

Male vs Female

Adults (25+) · Share within each education level

% male · % female

Less than 9th grade

0% · 100%

9th-12th, no diploma

28.1% · 71.9%

HS graduate

57.2% · 42.8%

Some college no degree

33.9% · 66.1%

Associates degree

30.8% · 69.2%

Bachelors degree

54% · 46%

Graduate or professional degree

31.6% · 68.4%

Educational Attainment Overview

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

Highest credential completed · adults 25+

	Buffalo	Sangamon County	Illinois
Population (25+)	344	136,639	8,767,004
Less than 9th grade	1.2%	1.5%	4.6%
9th–12th, no diploma	9.3%	4.3%	5%
High school diploma or GED	40.1%	28.1%	25.1%
Some college, no degree	16.3%	20.5%	19.2%
Associate's degree	7.6%	8.9%	8.3%
Bachelor's degree or higher	25.6%	36.6%	37.8%
Bachelor's degree	14.5%	21.8%	22.6%
Graduate or professional	11%	14.8%	15.3%
High School or higher	89.5%	94.1%	90.5%

Earnings by education level

percentage as applicable

Median Earnings

$51,719

Median earnings for adults 25+, by level

Less than HS graduate

$31,250

HS graduate

$55,357

Some college or associates

$52,917

Bachelors degree

$88,177

Graduate or professional degree

$43,929

Poverty Rate

for ages 25+, with bachelors degree or higher

Less than HS graduate

22.2%

HS graduate

31.2%

Some college or associates

8.5%

Bachelors degree or higher

Outcomes by Education Level

Earnings and poverty rates across education levels (25+)

Adults 25+

	Buffalo	Sangamon County	Illinois
Median earnings
Population 25+, with earnings	$51,719	$54,994	$55,582
Less than high school graduate	$31,250	$30,897	$34,655
High school graduate (includes equivalency)	$55,357	$39,258	$40,965
Some college or associate's degree	$52,917	$49,027	$47,813
Bachelor's degree	$88,177	$66,662	$73,326
Graduate or professional degree	$43,929	$83,598	$91,623
Poverty rates
Less than high school graduate	22.2%	34.5%	21.6%
High school graduate (includes equivalency)	31.2%	17.4%	14.4%
Some college or associate's degree	8.5%	9.2%	9.9%
Bachelor's degree or higher	0%	3.8%	4.5%

Insights for Buffalo, 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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