O'Fallon, MO demographics:
population, income, and more

Total population
101,784
1.4% year-over-year change
Median household income
$112,459/yr
3.6% year-over-year change
Housing units
39,147
1.6% year-over-year change

O'Fallon population

How many people live in O'Fallon

O'Fallon is home to 101,784 residents, according to the most recent Census data. Gender-wise, 49.2% of O'Fallon locals are male, and 50.8% are female.

Total population
101,784
1.4% year-over-year change
Gender ratio
Male
49.2%
50,121
Female
50.8%
51,663
Value Percent YoY change
Male 50,121 49.2% 0.4%
Female 51,663 50.8% 2.4%
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 O'Fallon is 39, with the population distributed as follows: about 19% are children under 15, then 11.8% are in the 15 to 24 age group. Adults between 25 and 44 make up 27% of the population, while another 27.4% fall into the 45 to 64 bracket. Finally, around 14.8% are 65 or older.

Median age
39
Age breakdown
Under 15
19%
15 to 24
11.8%
25 to 44
27%
45 to 64
27.4%
Over 65
14.8%
Value Percent YoY change
Under 15 19,316 19% -0.8%
15 to 24 12,050 11.8% -0.3%
25 to 44 27,428 27% 1.2%
45 to 64 27,923 27.4% 1.8%
Over 65 15,068 14.8% 5.6%
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 O'Fallon, 93% of the population are US-born citizens, while 4% have gained naturalized citizenship. At the same time, 3% of residents are non-citizens. As for race, 82% of locals are Caucasian, 4.7% are African American and 4.7% have Asian roots. There’s also a share of 7.3% that includes residents with two or more races.

Citizenship
U.S.-born citizens
93%
Non-U.S.-born citizens
4%
Non-citizens
3%
Value Percent YoY change
U.S.-born citizens 94,672 93% 0.7%
Non-U.S.-born citizens 4,058 4% 0.5%
Non-citizens 3,055 3% 34.0%
Racial breakdown
White
82%
Black or African American
4.7%
American Indian and Alaska Native
0%
Asian
4.7%
Native Hawaiian and other Pacific Islander
0%
Two or more races
7.3%
Other
1.2%
Value Percent
White 83,497 82%
Black or African American 4,780 4.7%
American Indian and Alaska Native 51 0%
Asian 4,816 4.7%
Native Hawaiian and other Pacific Islander 40 0%
Two or more races 7,409 7.3%
Other 1,192 1.2%

Households in O'Fallon

A peek inside O'Fallon households

O'Fallon has 38,256 households, with an average of 3 members in each. Of these, 72.6% are families, while the remaining 27.4% are made up of individuals living alone or with non-relatives, such as roommates.

Households stats

Total households
38,256
1.9% year-over-year change
Average people per household
3
Non-family households
10,488
Family households
27,768
Value Percent YoY change
Non-family households 10,488 27.4% 4.8%
Family households 27,768 72.6% 0.9%
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 O'Fallon

The housing landscape of O'Fallon

O'Fallon's housing consists of 39,147 units, with 75.5% being detached single-family homes ideal for those wanting space. Attached options, including duplexes and townhouses, make up 8.5% 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 4.3% of the housing landscape.

Housing units
39,147
1.6% year-over-year change
Housing types
Value Percent
1 unit, detached 29,570 75.5%
1 unit, attached 3,318 8.5%
2 units 129 0.3%
3 or 4 units 858 2.2%
5 to 9 units 930 2.4%
10 to 19 units 1,085 2.8%
20 to 49 units 808 2.1%
50 or more units 781 2%
Mobile home 1,667 4.3%
Homes built since 2020
1,246
43.2% year-over-year change

The age of buildings in O'Fallon

In O'Fallon, the median construction year is 1999. About 1% of homes were built before the 1940s, with another 0.4% going up by 1949. Most development happened in the second half of the 20th century. Then, 30.4% of homes were added from 2000 to 2009, 14.3% between 2010 and 2019, and 3.2% are part of the newest wave of development.

Construction year breakdown by decade
Value Percent YoY change
Built in 1939 or earlier 403 1% 19.9%
Built between 1940 and 1949 164 0.4% -7.3%
Built between 1950 and 1959 795 2% 1.0%
Built between 1960 and 1969 1,467 3.8% -8.8%
Built between 1970 and 1979 2,006 5.1% -1.7%
Built between 1980 and 1989 4,030 10.3% 2.1%
Built between 1990 and 1999 11,516 29.4% 3.8%
Built between 2000 and 2009 11,919 30.4% -3.3%
Built between 2010 and 2019 5,601 14.3% 4.6%
Built in 2020 or later 1,246 3.2% 43.2%
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.

O'Fallon occupancy rates

Out of the 38,256 occupied housing units in O'Fallon, 82% are owner-occupied, while 18% are lived in by tenants. Meanwhile, 2.3% of all homes on the local market sit vacant.

Occupied housing units
38,256
1.9% year-over-year change
Occupancy breakdown
Renter occupied
6,877
Owner occupied
31,379
Value Percent YoY
change
Renter occupied 6,877 18% -2.2%
Owner occupied 31,379 82% 2.9%
Unoccupied housing units
2.3%
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.

O'Fallon housing costs

Housing costs in O'Fallon come to a median of $1,600 per month, while tenants specifically pay a median gross rent of $1,392.

Median housing costs per month
$1,600/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 O'Fallon
$1,392/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 O'Fallon

O'Fallon education at a glance

About 29.1% of the population in O'Fallon went to high school, while 22.4% pursued college studies. Another 8.1% earned an associate degree and 25.3% hold a bachelor’s. Meanwhile, 13.6% went even further, earning a master’s or doctorate.

Education level
Value Percent YoY change
No high school 1,185 1.5% 3.3%
High school diploma 22,623 29.1% 3.1%
College diploma 17,442 22.4% 0.8%
Associate degree 6,284 8.1% -1.7%
Bachelor's degree 19,719 25.3% 2.7%
Graduate degree 10,555 13.6% 5.0%
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 O'Fallon

How much people earn in O'Fallon

The average annual household income in O'Fallon was $121,488 in 2024, the most recent annual data available, according to the U.S. Census Bureau. This marked a +2.8% change from the previous year. At the same time, the median income stood at $112,459, reflecting a +3.6% shift over the same period.

Average household income in O'Fallon
$121,488/year
2.8% year-over-year change
Median household income in O'Fallon
$112,459/year
3.6% year-over-year change

O'Fallon income by age

In O'Fallon, households led by residents aged 25 to 44 — usually in the early to mid stages of their careers — have a median income of $121,274. Those with someone between 45 and 64 in charge, often well established professionally, earn $141,483 overall. Younger households, where the main provider is under 25 and just starting out, report a median income of $72,210, while those led by someone over 65, many of whom may be retired, have about $72,090 in earnings. Overall, 94.4% of the locals in this community live above the poverty line.

Income breakdown by age
Value YoY change
Under 25 $72,210 -27.9%
25 - 44 $121,274 4.7%
45 - 64 $141,483 4.4%
Over 65 $72,090 3.0%
Above poverty level
94,487
Below poverty level
5,569
Value Percent YoY
change
Above poverty level 94,487 94.4% 0.8%
Below poverty level 5,569 5.6% 14.8%

Average renter income in O'Fallon

To get a better sense of what renters earn on average in O'Fallon, their median household income was $61,014 according to 2022 Census data. In addition, the rent-to-income ratio in the area, at 27.4%, shows what portion of their earnings goes toward housing expenses.

Renter median household income
$61,014
Rent-to-income ratio
27.4%
Understanding the rent-to-income ratio can help renters gauge if local housing costs align with their earnings. A ratio under 30% usually signals affordability, while exceeding this mark means rent is taking a larger-than-recommended bite out of income. That could make it harder for you to cover other costs like transportation, healthcare, or child care.

Employment in O'Fallon

Workforce and job types in O'Fallon

83.1% of the working population are employed in professional or administrative positions, while 16.9% are in hands-on or service-based jobs. Also, 7.1% run their own businesses, 74.5% are employed by private companies, and 9.4% work in the public sector.

Workforce demographics

White collar
47,425
Blue collar
9,656
Value Percent YoY change
White collar 47,425 83.1% 2.8%
Blue collar 9,656 16.9% 3.7%
Employer type
Self employees
7.1%
Private companies
74.5%
Governmental workers
9.4%
Not for profit companies
9%
Value Percent YoY change
Self employees 4,050 7.1% 4.0%
Private companies 42,509 74.5% 1.7%
Governmental workers 5,363 9.4% 5.0%
Not for profit companies 5,159 9% 10.2%

Transportation in O'Fallon

How people get around in O'Fallon

Commuting methods vary: 98.7% of residents travel by personal vehicle and 1.2% 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 45,494 98.7% 0.0%
Taxicab 16 0% 23.1%
Bus or trolleybus 2 0% 100.0%
Railroad 20 0% 11.1%
Bicycle 20 0% N/A
Walk 536 1.2% 24.1%
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 O'Fallon by zipcode?

Zipcode Population Number of households Median income Average income
63366 54,769 20,967 $100,621 $116,910
63368 46,966 17,271 $124,297 $140,983

Find your place

Explore more communities

FAQs about O'Fallon demographics 

What is the total population of O'Fallon?

O'Fallon has a total population of 101,784 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 +1.4% compared to a year ago.

What is the gender ratio in O'Fallon?

The gender ratio in O'Fallon is as follows:
  • 49.2% males (50,121 residents)
  • 50.8% females (51,663 residents)

What is the median age in O'Fallon?

The median age in O'Fallon is 39.

What is the age distribution of the population in O'Fallon?

The age distribution in O'Fallon is as follows:
  • Under 15: 19% (19,316 residents)
  • Ages 15-24: 11.8% (12,050 residents)
  • Ages 25-44: 27% (27,428 residents)
  • Ages 45-64: 27.4% (27,923 residents)
  • Over 65: 14.8% (15,068 residents)

What is the racial and ethnic makeup of O'Fallon?

The racial and ethnic makeup of O'Fallon is as follows:
  • White: 82% (83,497 residents)
  • Black or African American: 4.7% (4,780 residents)
  • American Indian and Alaska Native: 0% (51 residents)
  • Asian: 4.7% (4,816 residents)
  • Native Hawaiian and Other Pacific Islander: 0% (40 residents)
  • Two or More Races: 7.3% (7,409 residents)
  • Other: 1.2% (1,192 residents)

What percentage of the population in O'Fallon are U.S.-born citizens?

U.S.-born citizens represent 93% of the population in O'Fallon.

How many housing units are there in O'Fallon?

There are 39,147 housing units in O'Fallon, reflecting a +1.6% change compared to the previous year, according to the latest data from the U.S. Census Bureau.

How many households are in O'Fallon and what is the average household size?

O'Fallon has a total of 38,256 households, with an average of 3 people in each.

What is the median household income in O'Fallon?

O'Fallon has a median household income of $112,459, representing a +3.6% shift from the previous year, according to the U.S. Census Bureau.

What is the job market overview for O'Fallon?

Here’s a detailed breakdown of the local job market:

Job types:
  • White-collar workers: 83.1% (47,425 residents)
  • Blue-collar workers: 16.9% (9,656 residents)

Places of employment:
  • Self-employed: 7.1% (4,050 residents)
  • Private companies: 74.5% (42,509 residents)
  • Governmental workers: 9.4% (5,363 residents)
  • Not-for-profit companies: 9% (5,159 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