O'Fallon
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The O'Fallon album
Outdoors in O'Fallon
Parks & trails →Trails & parks © OpenStreetMap contributors · Conserved land: USGS PAD-US
About O'Fallon
City in Illinois, United StatesO'Fallon is a city in St. Clair County, Illinois, United States. The 2020 census listed the population at 32,289. The city is the second largest city in the Metro East region and Southern Illinois. It sits 5 miles (8.0 km) from Scott Air Force Base and 18 miles (29 km) from Downtown St. Louis. Like its namesake in St. Charles County, Missouri, O'Fallon is part of the St. Louis metro area. This makes O'Fallon (along with the two Troys in Illinois and Missouri) one of the few pairs of like-named municipalities to be part of the same metro region.
From Wikipedia, licensed CC BY-SA 4.0 · facts via Wikidata (CC0)
How O'Fallon ranks
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Housing in O'Fallon
The median sale price was $300,000 in May 2026.
A strong seller's market
Safety in O'Fallon
Safety Grade B
O'Fallon reports less crime per resident than 55% of the U.S. towns and cities we grade.
Health in O'Fallon
Health Grade A
Healthier than 88% of U.S. towns on seven CDC estimates.
Compared with Illinois
of 32 measures CDC estimates. The other 18 are too close to call.
What stands out
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Where O'Fallon is
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