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

Total population
66,876
-0.0% year-over-year change
Median household income
$65,604/yr
0.1% year-over-year change
Housing units
32,084
0.4% year-over-year change

Williamson County population

How many people live in Williamson County

Williamson County is home to 66,876 residents, according to the most recent Census data. Gender-wise, 50.2% of Williamson County locals are male, and 49.8% are female.

Total population
66,876
-0.0% year-over-year change
Gender ratio
Male
50.2%
33,585
Female
49.8%
33,291
Value Percent YoY change
Male 33,585 50.2% -0.2%
Female 33,291 49.8% 0.1%
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 Williamson County is 42, with the population distributed as follows: about 17.5% are children under 15, then 10.3% are in the 15 to 24 age group. Adults between 25 and 44 make up 26.5% of the population, while another 26.1% fall into the 45 to 64 bracket. Finally, around 19.6% are 65 or older.

Median age
41.6
Age breakdown
Under 15
17.5%
15 to 24
10.3%
25 to 44
26.5%
45 to 64
26.1%
Over 65
19.6%
Value Percent YoY change
Under 15 11,725 17.5% -1.7%
15 to 24 6,864 10.3% -1.2%
25 to 44 17,704 26.5% 0.8%
45 to 64 17,447 26.1% 0.5%
Over 65 13,136 19.6% 0.2%
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 Williamson County, 97.5% of the population are US-born citizens, while 1.6% have gained naturalized citizenship. At the same time, 1% of residents are non-citizens. As for race, 89% of locals are Caucasian, 4.5% are African American and 1.5% have Asian roots. There’s also a share of 4.5% that includes residents with two or more races.

Citizenship
U.S.-born citizens
97.5%
Non-U.S.-born citizens
1.6%
Non-citizens
1%
Value Percent YoY change
U.S.-born citizens 65,207 97.5% -0.2%
Non-U.S.-born citizens 1,036 1.6% 27.1%
Non-citizens 633 1% -18.6%
Racial breakdown
White
89%
Black or African American
4.5%
American Indian and Alaska Native
0.3%
Asian
1.5%
Native Hawaiian and other Pacific Islander
0%
Two or more races
4.5%
Other
0.3%
Value Percent
White 59,489 89%
Black or African American 2,988 4.5%
American Indian and Alaska Native 186 0.3%
Asian 1,000 1.5%
Two or more races 2,987 4.5%
Other 226 0.3%

Households in Williamson County

A peek inside Williamson County households

Williamson County has 28,983 households, with an average of 2 members in each. Of these, 62.8% are families, while the remaining 37.2% are made up of individuals living alone or with non-relatives, such as roommates.

Households stats

Total households
28,983
0.7% year-over-year change
Average people per household
2
Non-family households
10,777
Family households
18,206
Value Percent YoY change
Non-family households 10,777 37.2% 2.4%
Family households 18,206 62.8% -0.3%
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 Williamson County

The housing landscape of Williamson County

Williamson County's housing consists of 32,084 units, with 74.9% being detached single-family homes ideal for those wanting space. Attached options, including duplexes and townhouses, make up 1.5% 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 6.8% of the housing landscape.

Housing units
32,084
0.4% year-over-year change
Housing types
Value Percent
1 unit, detached 24,045 74.9%
1 unit, attached 494 1.5%
2 units 2,118 6.6%
3 or 4 units 1,418 4.4%
5 to 9 units 984 3.1%
10 to 19 units 312 1%
20 to 49 units 171 0.5%
50 or more units 303 0.9%
Mobile home 2,178 6.8%
Boat, RV, van, etc. 61 0.2%
Homes built since 2020
411
96.7% year-over-year change

The age of buildings in Williamson County

In Williamson County, the median construction year is 1981. About 14.7% of homes were built before the 1940s, with another 5% going up by 1949. Most development happened in the second half of the 20th century. Then, 15% of homes were added from 2000 to 2009, 11.2% between 2010 and 2019, and 1.3% are part of the newest wave of development.

Construction year breakdown by decade
Value Percent YoY change
Built in 1939 or earlier 4,703 14.7% 3.4%
Built between 1940 and 1949 1,605 5% -7.7%
Built between 1950 and 1959 2,179 6.8% 7.3%
Built between 1960 and 1969 2,890 9% 3.0%
Built between 1970 and 1979 4,318 13.5% -5.6%
Built between 1980 and 1989 3,589 11.2% -0.2%
Built between 1990 and 1999 3,977 12.4% -3.7%
Built between 2000 and 2009 4,803 15% 1.2%
Built between 2010 and 2019 3,609 11.2% 0.9%
Built in 2020 or later 411 1.3% 96.7%
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.

Williamson County occupancy rates

Out of the 28,983 occupied housing units in Williamson County, 70.6% are owner-occupied, while 29.4% are lived in by tenants. Meanwhile, 9.7% of all homes on the local market sit vacant.

Occupied housing units
28,983
0.7% year-over-year change
Occupancy breakdown
Renter occupied
8,506
Owner occupied
20,477
Value Percent YoY
change
Renter occupied 8,506 29.4% 2.4%
Owner occupied 20,477 70.6% 0.1%
Unoccupied housing units
9.7%
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.

Williamson County housing costs

Housing costs in Williamson County come to a median of $950 per month, while tenants specifically pay a median gross rent of $930.

Median housing costs per month
$950/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 Williamson County
$930/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 Williamson County

Williamson County education at a glance

About 35% of the population in Williamson County went to high school, while 26.3% pursued college studies. Another 11.8% earned an associate degree and 15.2% hold a bachelor’s. Meanwhile, 9.8% went even further, earning a master’s or doctorate.

Education level
Value Percent YoY change
No high school 986 1.9% -18.3%
High school diploma 18,451 35% 2.4%
College diploma 13,864 26.3% 1.2%
Associate degree 6,206 11.8% 4.4%
Bachelor's degree 8,006 15.2% -4.2%
Graduate degree 5,136 9.8% -2.4%
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 Williamson County

How much people earn in Williamson County

The average annual household income in Williamson County was $85,846 in 2024, the most recent annual data available, according to the U.S. Census Bureau. This marked a +0.3% change from the previous year. At the same time, the median income stood at $65,604, reflecting a +0.1% shift over the same period.

Average household income in Williamson County
$85,846/year
0.3% year-over-year change
Median household income in Williamson County
$65,604/year
0.1% year-over-year change

Williamson County income by age

In Williamson County, households led by residents aged 25 to 44 — usually in the early to mid stages of their careers — have a median income of $76,561. Those with someone between 45 and 64 in charge, often well established professionally, earn $84,340 overall. Younger households, where the main provider is under 25 and just starting out, report a median income of $43,419, while those led by someone over 65, many of whom may be retired, have about $46,501 in earnings. Overall, 86.3% of the locals in this community live above the poverty line.

Income breakdown by age
Value YoY change
Under 25 $43,419 -0.2%
25 - 44 $76,561 1.2%
45 - 64 $84,340 2.8%
Over 65 $46,501 1.6%
Above poverty level
55,089
Below poverty level
8,776
Value Percent YoY
change
Above poverty level 55,089 86.3% 0.6%
Below poverty level 8,776 13.7% -3.1%

Employment in Williamson County

Workforce and job types in Williamson County

The job market in Williamson County is powered by 30,212 working residents, spread across a range of industries and roles. 76.8% of the working population are employed in professional or administrative positions, while 23.2% are in hands-on or service-based jobs. Also, 9.5% run their own businesses, 60.2% are employed by private companies, and 20.5% work in the public sector.

Workforce demographics

Working population
30,212
0.5% year-over-year change
White collar
23,205
Blue collar
7,007
Value Percent YoY change
White collar 23,205 76.8% -1.0%
Blue collar 7,007 23.2% 5.8%
Employer type
Self employees
9.5%
Private companies
60.2%
Governmental workers
20.5%
Not for profit companies
9.8%
Value Percent YoY change
Self employees 2,868 9.5% 0.3%
Private companies 18,196 60.2% 3.5%
Governmental workers 6,187 20.5% 2.2%
Not for profit companies 2,961 9.8% -17.0%
Unemployment rate
5.0%
17.1% year-over-year change

Available workforce

The unemployment rate in Williamson County stands at 5%, 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 Williamson County

How people get around in Williamson County

Commuting methods vary: 89.3% of residents travel by personal vehicle and 0.5% 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 26,482 89.3% 0.7%
Taxicab 10 0% -83.9%
Bus or trolleybus 88 0.3% 8.6%
Railroad 2 0% 0.0%
Motorcycle 115 0.4% 3.6%
Bicycle 31 0.1% -49.2%
Walk 135 0.5% -42.5%
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 Williamson County by zipcode?

Zipcode Population Number of households Median income Average income
62841 118 53 $31,750 $57,855
62915 384 215 $31,875 $45,401
62917 2,303 986 $50,119 $103,110
62918 10,658 4,521 $70,920 $94,171
62921 233 115 $0 $55,530
62922 2,608 1,065 $74,245 $98,691
62890 2,377 989 $54,271 $67,371
62896 10,627 4,501 $55,458 $70,921
62901 22,946 9,910 $35,089 $55,302
62902 4,135 1,841 $84,223 $120,373

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FAQs about Williamson County demographics 

What is the total population of Williamson County?

Williamson County has a total population of 66,876 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 -0.0% compared to a year ago.

What is the gender ratio in Williamson County?

The gender ratio in Williamson County is as follows:
  • 50.2% males (33,585 residents)
  • 49.8% females (33,291 residents)

What is the median age in Williamson County?

The median age in Williamson County is 41.6.

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

The age distribution in Williamson County is as follows:
  • Under 15: 17.5% (11,725 residents)
  • Ages 15-24: 10.3% (6,864 residents)
  • Ages 25-44: 26.5% (17,704 residents)
  • Ages 45-64: 26.1% (17,447 residents)
  • Over 65: 19.6% (13,136 residents)

What is the racial and ethnic makeup of Williamson County?

The racial and ethnic makeup of Williamson County is as follows:
  • White: 89% (59,489 residents)
  • Black or African American: 4.5% (2,988 residents)
  • American Indian and Alaska Native: 0.3% (186 residents)
  • Asian: 1.5% (1,000 residents)
  • Native Hawaiian and Other Pacific Islander: 0% (0 residents)
  • Two or More Races: 4.5% (2,987 residents)
  • Other: 0.3% (226 residents)

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

U.S.-born citizens represent 97.5% of the population in Williamson County.

How many housing units are there in Williamson County?

There are 32,084 housing units in Williamson County, reflecting a +0.4% change compared to the previous year, according to the latest data from the U.S. Census Bureau.

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

Williamson County has a total of 28,983 households, with an average of 2 people in each.

What is the median household income in Williamson County?

Williamson County has a median household income of $65,604, representing a +0.1% shift from the previous year, according to the U.S. Census Bureau.

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

The employment rate is 95% in Williamson County, with a workforce of 30,212 residents. Here’s a detailed breakdown of the local job market:

Job types:
  • White-collar workers: 76.8% (23,205 residents)
  • Blue-collar workers: 23.2% (7,007 residents)

Places of employment:
  • Self-employed: 9.5% (2,868 residents)
  • Private companies: 60.2% (18,196 residents)
  • Governmental workers: 20.5% (6,187 residents)
  • Not-for-profit companies: 9.8% (2,961 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