Jefferson County, IL demographics:
population, income, and more

Total population
36,550
-0.7% year-over-year change
Median household income
$63,118/yr
3.3% year-over-year change
Housing units
16,629
-0.1% year-over-year change

Jefferson County population

How many people live in Jefferson County

Jefferson County is home to 36,550 residents, according to the most recent Census data. Gender-wise, 51.6% of Jefferson County locals are male, and 48.4% are female.

Total population
36,550
-0.7% year-over-year change
Gender ratio
Male
51.6%
18,871
Female
48.4%
17,679
Value Percent YoY change
Male 18,871 51.6% -0.4%
Female 17,679 48.4% -1.0%
A higher population often means more rental variety and livelier areas. The gender balance—how many men live here compared to women—can reveal a lot about the community and the lifestyles of its residents. Use this info to get a sense of the area's pace and personality.

Age demographics

The median age in Jefferson County is 41, with the population distributed as follows: about 18.3% are children under 15, then 11.1% are in the 15 to 24 age group. Adults between 25 and 44 make up 24.8% of the population, while another 25.7% fall into the 45 to 64 bracket. Finally, around 20% are 65 or older.

Median age
41.2
Age breakdown
Under 15
18.3%
15 to 24
11.1%
25 to 44
24.8%
45 to 64
25.7%
Over 65
20%
Value Percent YoY change
Under 15 6,704 18.3% -2.2%
15 to 24 4,071 11.1% -1.0%
25 to 44 9,078 24.8% 0.2%
45 to 64 9,399 25.7% -1.3%
Over 65 7,298 20% 0.5%
The age composition helps you get insight into who lives in the area. A younger population might mean a more active, fast-paced vibe, while an older one could suggest a quieter, slower lifestyle. If there's a balanced makeup, you’re likely to find a variety of services, housing types, and community spaces that cater to different life stages.

Racial makeup

In Jefferson County, 97.7% of the population are US-born citizens, while 1.5% have gained naturalized citizenship. At the same time, 0.8% of residents are non-citizens. As for race, 84% of locals are Caucasian, 6.2% are African American and 1% have Asian roots. There’s also a share of 7.6% that includes residents with two or more races.

Citizenship
U.S.-born citizens
97.7%
Non-U.S.-born citizens
1.5%
Non-citizens
0.8%
Value Percent YoY change
U.S.-born citizens 35,695 97.7% -0.8%
Non-U.S.-born citizens 545 1.5% -7.3%
Non-citizens 310 0.8% 24.5%
Racial breakdown
White
84%
Black or African American
6.2%
American Indian and Alaska Native
0.3%
Asian
1%
Native Hawaiian and other Pacific Islander
0%
Two or more races
7.6%
Other
0.9%
Value Percent
White 30,687 84%
Black or African American 2,272 6.2%
American Indian and Alaska Native 122 0.3%
Asian 376 1%
Two or more races 2,776 7.6%
Other 317 0.9%

Households in Jefferson County

A peek inside Jefferson County households

Jefferson County has 14,820 households, with an average of 2 members in each. Of these, 63.8% are families, while the remaining 36.2% are made up of individuals living alone or with non-relatives, such as roommates.

Households stats

Total households
14,820
0.1% year-over-year change
Average people per household
2
Non-family households
5,371
Family households
9,449
Value Percent YoY change
Non-family households 5,371 36.2% 4.6%
Family households 9,449 63.8% -2.3%
The mix between family and non-family households gives a glimpse into daily life. A higher percentage of families might mean more parks and schools, while more non-family setups can mean flexible housing and diverse living styles. For renters, this can signal what kinds of homes are common and can help you figure out if the area matches your lifestyle.

Housing in Jefferson County

The housing landscape of Jefferson County

Jefferson County's housing consists of 16,629 units, with 69% being detached single-family homes ideal for those wanting space. Attached options, including duplexes and townhouses, make up 0.8% and offer a more compact, shared living style. Then there are the multifamily buildings in the area, and for those seeking flexibility, non-traditional options like mobile homes account for 17% of the housing landscape.

Housing units
16,629
-0.1% year-over-year change
Housing types
Value Percent
1 unit, detached 11,479 69%
1 unit, attached 130 0.8%
2 units 213 1.3%
3 or 4 units 572 3.4%
5 to 9 units 467 2.8%
10 to 19 units 420 2.5%
20 to 49 units 187 1.1%
50 or more units 317 1.9%
Mobile home 2,819 17%
Boat, RV, van, etc. 25 0.2%
Homes built since 2020
141
42.4% year-over-year change

The age of buildings in Jefferson County

In Jefferson County, the median construction year is 1977. About 11.1% of homes were built before the 1940s, with another 6.5% going up by 1949. Most development happened in the second half of the 20th century. Then, 10.8% of homes were added from 2000 to 2009, 5% between 2010 and 2019, and 0.8% are part of the newest wave of development.

Construction year breakdown by decade
Value Percent YoY change
Built in 1939 or earlier 1,851 11.1% -1.5%
Built between 1940 and 1949 1,074 6.5% -4.6%
Built between 1950 and 1959 1,729 10.4% -9.2%
Built between 1960 and 1969 1,395 8.4% 5.9%
Built between 1970 and 1979 3,081 18.5% 2.5%
Built between 1980 and 1989 2,019 12.1% -4.0%
Built between 1990 and 1999 2,702 16.2% 6.2%
Built between 2000 and 2009 1,801 10.8% -1.7%
Built between 2010 and 2019 836 5% -0.5%
Built in 2020 or later 141 0.8% 42.4%
As a renter, knowing when homes were built helps you understand the potential condition and design of rental units. Newer builds may have more contemporary layouts, while older homes can offer character or larger lots, depending on the area.

Jefferson County occupancy rates

Out of the 14,820 occupied housing units in Jefferson County, 71.7% are owner-occupied, while 28.3% are lived in by tenants. Meanwhile, 10.9% of all homes on the local market sit vacant.

Occupied housing units
14,820
0.1% year-over-year change
Occupancy breakdown
Renter occupied
4,197
Owner occupied
10,623
Value Percent YoY
change
Renter occupied 4,197 28.3% 0.7%
Owner occupied 10,623 71.7% -0.1%
Unoccupied housing units
10.9%
Unoccupied housing units refer to homes that are currently without residents—whether they're waiting for renters or owners, used seasonally, or simply unclaimed. A higher share of empty homes may mean more housing availability, while a low number can reflect a tighter market with more competition. This, along with the renter-vs.-owner mix, helps paint a clearer picture of what types of housing and services are likely to be available in the area.

Jefferson County housing costs

Housing costs in Jefferson County come to a median of $877 per month, while tenants specifically pay a median gross rent of $885.

Median housing costs per month
$877/month
This figure sums up typical monthly housing costs for all households in the area. If you own, it includes mortgage payments in addition to property taxes, insurance and HOA fees. If you rent, it accounts for rent plus extras like utilities. It’s useful for seeing how local living expenses stack up compared to other places.
Median gross rent in Jefferson County
$885/month
Gross rent gives a more complete look at what renters actually pay, including not just base rent, but also utilities and fees. It’s a key number for evaluating rental affordability in your area of interest and understanding how it compares to nearby locations.

Education in Jefferson County

Jefferson County education at a glance

About 41.6% of the population in Jefferson County went to high school, while 25.7% pursued college studies. Another 13.2% earned an associate degree and 10.8% hold a bachelor’s. Meanwhile, 6.2% went even further, earning a master’s or doctorate.

Education level
Value Percent YoY change
No high school 714 2.5% -6.0%
High school diploma 11,805 41.6% 1.4%
College diploma 7,314 25.7% -5.0%
Associate degree 3,742 13.2% 4.2%
Bachelor's degree 3,077 10.8% -0.4%
Graduate degree 1,758 6.2% -0.4%
A community’s education mix can offer insights into the local economy and housing market. Higher levels of education often align with more job opportunities and stable incomes, which can increase demand for homes and influence both rent prices and rental availability.

Income in Jefferson County

How much people earn in Jefferson County

The average annual household income in Jefferson County was $80,324 in 2024, the most recent annual data available, according to the U.S. Census Bureau. This marked a +3.6% change from the previous year. At the same time, the median income stood at $63,118, reflecting a +3.3% shift over the same period.

Average household income in Jefferson County
$80,324/year
3.6% year-over-year change
Median household income in Jefferson County
$63,118/year
3.3% year-over-year change

Jefferson County income by age

In Jefferson County, households led by residents aged 25 to 44 — usually in the early to mid stages of their careers — have a median income of $64,381. Those with someone between 45 and 64 in charge, often well established professionally, earn $72,534 overall. Younger households, where the main provider is under 25 and just starting out, report a median income of $55,607, while those led by someone over 65, many of whom may be retired, have about $52,038 in earnings. Overall, 86.6% of the locals in this community live above the poverty line.

Income breakdown by age
Value YoY change
Under 25 $55,607 4.7%
25 - 44 $64,381 3.1%
45 - 64 $72,534 1.3%
Over 65 $52,038 7.0%
Above poverty level
29,955
Below poverty level
4,654
Value Percent YoY
change
Above poverty level 29,955 86.6% 0.3%
Below poverty level 4,654 13.4% -4.7%

Employment in Jefferson County

Workforce and job types in Jefferson County

The job market in Jefferson County is powered by 16,340 working residents, spread across a range of industries and roles. 67.5% of the working population are employed in professional or administrative positions, while 32.5% are in hands-on or service-based jobs. Also, 9.4% run their own businesses, 69% are employed by private companies, and 12.5% work in the public sector.

Workforce demographics

Working population
16,340
1.5% year-over-year change
White collar
11,034
Blue collar
5,306
Value Percent YoY change
White collar 11,034 67.5% 2.8%
Blue collar 5,306 32.5% -1.2%
Employer type
Self employees
9.4%
Private companies
69%
Governmental workers
12.5%
Not for profit companies
9%
Value Percent YoY change
Self employees 1,538 9.4% 8.8%
Private companies 11,278 69% 1.1%
Governmental workers 2,046 12.5% 6.3%
Not for profit companies 1,478 9% -7.8%
Unemployment rate
5.8%
-11.2% year-over-year change

Available workforce

The unemployment rate in Jefferson County stands at 5.8%, representing the share of the workforce currently without a job and actively looking for one.

For renters, the unemployment rate helps paint a picture of job security and financial stability in the area. Rates around 4% to 5% are considered typical. A lower-than-average rate might suggest strong job prospects and a thriving local economy, while a higher rate could hint at fewer opportunities—both useful to consider when planning a move.

Transportation in Jefferson County

How people get around in Jefferson County

Commuting methods vary: 92.2% of residents travel by personal vehicle and 0.7% prefer to walk, while the remaining share relies on public transit or on two wheelers to get from A to B.

Means of transportation
Value Percent YoY change
Car 14,797 92.2% 1.6%
Taxicab 113 0.7% -6.6%
Bus or trolleybus 36 0.2% 12.5%
Ferryboat 9 0.1% N/A
Motorcycle 6 0% 50.0%
Bicycle 4 0% 0.0%
Walk 106 0.7% -36.1%
Understanding how locals get to work can help you plan your own routine. High car usage might mean you’ll need a vehicle, while strong public transit or walkability could save you the hassle. Commute times also play a big role in quality of life—shorter trips can give you more time for the things you enjoy.

What is the median and average household income in Jefferson County by zipcode?

Zipcode Population Number of households Median income Average income
62814 1,668 652 $59,462 $76,805
62816 1,133 540 $53,036 $61,368
62830 1,416 588 $62,400 $71,219
62846 1,798 318 $65,500 $77,005
62801 19,827 7,801 $52,017 $69,768
62808 1,602 604 $69,015 $85,283
62810 1,188 470 $57,969 $71,428
62864 22,779 9,680 $60,451 $80,400
62872 1,153 435 $62,344 $79,980
62883 693 234 $104,808 $124,729

Find your place

Explore more communities

FAQs about Jefferson County demographics 

What is the total population of Jefferson County?

Jefferson County has a total population of 36,550 residents, according to the latest release from the U.S. Census Bureau: the 2019-2023 American Community Survey (ACS) 5-year estimates. This figure changed by -0.7% compared to a year ago.

What is the gender ratio in Jefferson County?

The gender ratio in Jefferson County is as follows:
  • 51.6% males (18,871 residents)
  • 48.4% females (17,679 residents)

What is the median age in Jefferson County?

The median age in Jefferson County is 41.2.

What is the age distribution of the population in Jefferson County?

The age distribution in Jefferson County is as follows:
  • Under 15: 18.3% (6,704 residents)
  • Ages 15-24: 11.1% (4,071 residents)
  • Ages 25-44: 24.8% (9,078 residents)
  • Ages 45-64: 25.7% (9,399 residents)
  • Over 65: 20% (7,298 residents)

What is the racial and ethnic makeup of Jefferson County?

The racial and ethnic makeup of Jefferson County is as follows:
  • White: 84% (30,687 residents)
  • Black or African American: 6.2% (2,272 residents)
  • American Indian and Alaska Native: 0.3% (122 residents)
  • Asian: 1% (376 residents)
  • Native Hawaiian and Other Pacific Islander: 0% (0 residents)
  • Two or More Races: 7.6% (2,776 residents)
  • Other: 0.9% (317 residents)

What percentage of the population in Jefferson County are U.S.-born citizens?

U.S.-born citizens represent 97.7% of the population in Jefferson County.

How many housing units are there in Jefferson County?

There are 16,629 housing units in Jefferson County, reflecting a -0.1% change compared to the previous year, according to the latest data from the U.S. Census Bureau.

How many households are in Jefferson County and what is the average household size?

Jefferson County has a total of 14,820 households, with an average of 2 people in each.

What is the median household income in Jefferson County?

Jefferson County has a median household income of $63,118, representing a +3.3% shift from the previous year, according to the U.S. Census Bureau.

What is the employment rate and job market overview for Jefferson County?

The employment rate is 94.2% in Jefferson County, with a workforce of 16,340 residents. Here’s a detailed breakdown of the local job market:

Job types:
  • White-collar workers: 67.5% (11,034 residents)
  • Blue-collar workers: 32.5% (5,306 residents)

Places of employment:
  • Self-employed: 9.4% (1,538 residents)
  • Private companies: 69% (11,278 residents)
  • Governmental workers: 12.5% (2,046 residents)
  • Not-for-profit companies: 9% (1,478 residents)

Data source & methodology

The demographic data on this page was sourced from the latest U.S. Census Bureau release—the 2019–2023 American Community Survey (ACS) 5-year estimates.

The information, issued annually, is compiled and published by the Point2Homes Research Team as soon as new data becomes available.

No representation, guarantee, or warranty is made concerning the accuracy or completeness of modified or aggregated information for particular areas.

Page last updated: September 2025