The Town FilesO'Fallon, Illinois
City in St. Clair County · population 32,289 (2020 Census)
- Median home
- $295,700
- Household income
- $105,982
- Jan low / Jul high
- 24° / 90°
- Snow a year
- 11 in
- Tornadoes ≤10 mi since 1950
- 40
- Median age
- 37.8
O'Fallon is a city of 32,289 people in St. Clair County, Illinois. The median home is worth $295,700, above the typical Illinois town ($156,600). It ranks better for young professionals than 92% of Illinois towns, more upscale than 89% of Illinois towns, better for first-time buyers than 76% of Illinois towns.
How O'Fallon ranks
Percentile among Illinois towns with at least 500 people on The Town Files lifestyle rankings. 50 is typical for the state; 90 means better than 90% of Illinois towns.
Homes and cost of living
The median home in O'Fallon is worth $295,700, above the typical Illinois town ($156,600). Homes cost about 2.8 times the median household income of $105,982, which is more affordable than 27% of Illinois towns. Median rent is $1,332 a month. 70.2% of households own their home.
| Housing | O'Fallon | Typical Illinois town |
|---|---|---|
| Median home value | $295,700 | $156,600 |
| Median rent | $1,332 | $960 |
| Median household income | $105,982 | $72,500 |
| Home value ÷ income | 2.8× | 2.2× |
| Homeownership | 70.2% | 76.6% |
| Median year built | 1997 | 1967 |
| Seasonal / vacation homes | 0.8% | — |
Who lives in O'Fallon
| People | O'Fallon | Typical Illinois town |
|---|---|---|
| Median age | 37.8 | 40.4 |
| Age 65 and over | 16.7% | 18.7% |
| Under 18 | 26.2% | — |
| Bachelor's degree or higher | 52.4% | 21.8% |
| Below the poverty line | 6.2% | 9.9% |
| Veterans | 20.2% | — |
| Born outside the U.S. | 3.8% | — |
| Work from home | 20.4% | 8.9% |
| Average commute | 25.3 min | 26.1 min |
| Homes with broadband | 94.5% | 90.4% |
Weather in O'Fallon
July highs average 90.2°F and January lows 24.3°F. About 43.4 inches of rain and melted snow fall a year, with 11.2 inches of snow (typical Illinois town: 24.2 in). Expect about 53 days a year at 90°F or hotter and 94 nights at or below freezing.
Tornadoes, storms and disasters
40 tornadoes have passed within 10 miles of O'Fallon since 1950, compared with 27 for the typical Illinois town. 12 rated (E)F2 or stronger. The strongest, an F4, struck on February 25, 1956 about 1.7 miles from the town center and killed 6. Tornadoes within 10 miles have caused 7 deaths and 59 injuries since 1950. The most recent was on April 27, 2026.
Hail of 1 inch or larger has been reported within 10 miles 149 times; the largest was 3.50 inches on April 28, 2012.
Severe weather in St. Clair County since 1996
St. Clair County has been included in 19 federal disaster or emergency declarations since 1953, most often for flood, tornado, hurricane.
| Declared | Incident | Declaration |
|---|---|---|
| September 20, 2024 | Flood | DR-4819: Severe Storms, Tornadoes, Straight-Line Winds, And Floodng |
| October 14, 2022 | Flood | DR-4676: Severe Storm And Flooding |
| March 26, 2020 | Biological | DR-4489: Covid-19 Pandemic |
| March 13, 2020 | Biological | EM-3435: Covid-19 |
| September 19, 2019 | Flood | DR-4461: Severe Storms And Flooding |
Jobs and pay in St. Clair County
St. Clair County had 89,981 jobs in 2024, paying an average of $57,001 a year. Unemployment was 4.6% in 2023; in O'Fallon itself the ACS puts it at 3.7%.
Public schools in O'Fallon
10 public schools with 7,177 students, about 16.8 students per teacher.
| School | Grades | Students | Per teacher |
|---|---|---|---|
| O Fallon High School | 9-12 | 2,559 | 16.5 |
| Amelia V Carriel Jr High | 6-8 | 695 | 19.9 |
| Fulton Jr High School | 6-8 | 659 | 19.4 |
| Marie Schaefer Elem School | PK-5 | 641 | 18.9 |
| Delores Moye Elem School | PK-5 | 582 | 14.6 |
| Estelle Kampmeyer Elem School | PK-5 | 489 | 17.5 |
| J Emmett Hinchcliffe Sr Elem Sch | PK-5 | 482 | 18.5 |
| Laverna Evans Elem School | PK-5 | 434 | 20.7 |
| Dawn Elser Elementary School | PK-4 | 384 | 11.0 |
| Joseph Arthur Middle School | 5-8 | 252 | 12.6 |
Towns near O'Fallon
- Shiloh, IL3.3 mi · 14,098 people · home $274,000
- Fairview Heights, IL4.8 mi · 16,706 people · home $177,700
- Swansea, IL5.1 mi · 14,386 people · home $223,600
- Scott AFB, IL5.2 mi · 3,688 people · home —
- Lebanon, IL5.7 mi · 4,691 people · home $170,700
- Caseyville, IL6.7 mi · 4,400 people · home $96,800
- Belleville, IL7.1 mi · 42,404 people · home $141,300
- Collinsville, IL7.3 mi · 24,366 people · home $163,600
O'Fallon questions
Is O'Fallon, Illinois a good place to retire?
On The Town Files lifestyle rankings, O'Fallon scores better for retirees than 35% of Illinois towns and quieter than 14%. 16.7% of residents are 65 or older (median age 37.8).
How much does a house cost in O'Fallon?
The median owner-occupied home in O'Fallon is valued at $295,700 (Census ACS 2020–2024), against a median household income of $105,982, so homes cost about 2.8 times income. Median rent is $1,332 a month.
What is the weather like in O'Fallon?
July highs average 90.2°F and January lows 24.3°F (NOAA 1991–2020 normals). It gets about 43.4 inches of precipitation a year and 11.2 inches of snow.
Does O'Fallon get tornadoes?
40 tornadoes have passed within 10 miles of O'Fallon since 1950 (NOAA Storm Events); the strongest was a F4 on February 25, 1956. The typical Illinois town has had 27.
- U.S. Census Bureau, American Community Survey 5-year estimates (2020–2024)
- U.S. Census Bureau, 2020 Census and 2025 Gazetteer (2020 / 2025)
- NOAA NCEI U.S. Climate Normals (1991–2020)
- NOAA NCEI Storm Events Database (1950–2026)
- FEMA OpenFEMA Disaster Declarations (this product uses the FEMA OpenFEMA API but is not endorsed by FEMA) (1953–2026)
- NCES Common Core of Data (2023–24)
- BLS Quarterly Census of Employment and Wages; USDA ERS county unemployment (BLS LAUS) (2000–2024)
- The Town Files lifestyle rankings, built from federal demographic, school, crime and housing data (2025)