Auburn, IL Profile: Facts & Data

Auburn, Illinois - Basic Facts

The City of Auburn had a population of 4,392 as of July 1, 2025.

The primary coordinate point for Auburn is located at latitude 39.5917 and longitude -89.7465 in Sangamon County. The formal boundaries for the City of Auburn encompass a land area of 4.13 sq. miles and a water area of 0 sq. miles. Sangamon County is in the Central time zone (GMT -6).

The City of Auburn has a C1 Census Class Code which indicates an active incorporated place that does not serve as a county subdivision equivalent. It also has a Functional Status Code of "A" which identifies an active government providing primary general-purpose functions.

The City of Auburn is located within Township of Auburn, a minor civil division (MCD) of Sangamon County.

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Auburn, IL Data & Demographics (As of July 1, 2025)

POPULATION
Total Population	4,392 (100%)
Population in Households	4,344 (98.9%)
Population in Families	3,610 (82.2%)
Population in Group Quarters¹	48 ( 1.1%)
Population Density	1,065
Diversity Index²	20


INCOME
Median Household Income	$107,163
Average Household Income	$121,497
% of Income for Mortgage⁴	13%
Per Capita Income	$49,209
Wealth Index⁵	104
Socioeconomic Status Index⁶	Moderate (57.7)

HOUSING
Total HU (Housing Units)	1,914 (100%)
Owner Occupied HU	1,393 (72.8%)
Renter Occupied HU	385 (20.1%)
Vacant Housing Units	136 ( 7.1%)
Median Home Value	$222,059
Average Home Value	$259,404
Housing Affordability Index³	150

HOUSEHOLDS
Total Households	1,778
Average Household Size	2.44
Family Households	1,212
Average Family Size	3.00

HOUSING

Total HU (Housing Units)

1,914 (100%)

Owner Occupied HU

1,393 (72.8%)

Renter Occupied HU

385 (20.1%)

Vacant Housing Units

136 ( 7.1%)

Median Home Value

$222,059

Average Home Value

$259,404

Housing Affordability Index³

150

HOUSEHOLDS

Total Households

1,778

Average Household Size

2.44

Family Households

1,212

Average Family Size

3.00

NOTES

Group Quarters - a place where people live or stay in a group living arrangement. Includes college residents halls, nursing facilities, military barracks, and correctional facilities.
The Diversity Index is a scale of 0 to 100 that represents the likelihood that two persons, chosen at random from the same area, belong to different races or ethnic groups. If an area's entire population belongs to one race AND one ethnic group, then the area has zero diversity. An area's diversity index increases to 100 when the population is evenly divided into two or more race/ethnic groups.
The Housing Affordability Index base is 100 and represents a balance point where a resident with a median household income can normally qualify to purchase a median price home. Values above 100 indicate increased affordability, while values below 100 indicate decreased affordability.
The % of Income for Mortgage quantifies the percentage of median household income dedicated to mortgage payments on a home priced at the median value (assuming a 30-year mortgage and a 20% down payment).
The Wealth Index is based on a number of indicators of affluence including average household income and average net worth, but it also includes the value of material possessions and resources. It represents the wealth of the area relative to the national level. Values above or below 100 represent above-average wealth or below-average wealth compared to the national level.
The Socioeconomic Index ranges from zero (lowest relative status) to 100 (highest relative status). This measure quantifies disparities in social position of an area's inhabitants and is built from a broad range of demographic, housing, and socioeconomic inputs. More information on this measure can be found in Esri's SEI tutorial.

GROWTH RATE / YEAR	2020-2025	2025-2030
Population	-0.77%	-0.46%
Households	-0.09%	-0.06%
Families		-0.20%
Median Household Income		1.49%
Per Capita Income		2.11%
Owner Occupied HU		0.01%

GROWTH RATE / YEAR

2020-2025

2025-2030

Population

-0.77%

-0.46%

Households

-0.09%

-0.06%

Families

-0.20%

Median Household Income

1.49%

Per Capita Income

2.11%

Owner Occupied HU

0.01%

Auburn, IL - Peer Comparisons by Rank and Percentile

The table below compares Auburn to the other 1,461 incorporated cities, towns and CDPs in Illinois by rank and percentile using July 1, 2025 data. The location Ranked # 1 has the highest value. A location that ranks higher than 75% of its peers would be in the 75th percentile of the peer group.

Variable Description	Rank	Percentile
Total Population	# 358	76th
Population Density	# 649	56th
Median Household Income	# 218	85th
Housing Affordability Index	# 967	66th
Per Capita Income	# 327	78th
Diversity Index	# 808	45th

Variable Description

Rank

Percentile

Total Population

# 358

76th

Population Density

# 649

56th

Median Household Income

# 218

85th

Housing Affordability Index

# 967

66th

Per Capita Income

# 327

78th

Diversity Index

# 808

45th

Illinois Census Data Comparison Tool

Auburn, IL Profile: Facts & Data

Auburn, Illinois - Basic Facts

Auburn, IL Data & Demographics (As of July 1, 2025)

POPULATION

INCOME

HOUSING

HOUSEHOLDS

GROWTH RATE / YEAR

Auburn, IL - Peer Comparisons by Rank and Percentile

Auburn, IL - Most Popular Things to Do

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Sangamon County