O'Fallon in numbers
- Coordinates
- 38.5923, -89.9112
- Population
- 29 002
- Region
- Illinois
- Country
- United States, North America
- Capital
- Washington, D.C. — 1116 km away
- Same name
- 2 more places in the world share this name
Check the current local time in O'Fallon, Illinois, United States, which sits in the America/Chicago time zone (−6).
O'Fallon, United States
Sunday, 15 November 2026
UTC−6 · America/Chicago
Local time in O'Fallon
UTC−6 · no daylight saving time
O'Fallon keeps America/Chicago clock_time.
Sunrise 6:43 AM Solar noon 11:46 AM Sunset 4:48 PM Daylight 10 h 05 min Night 13 h 55 min Civil twilight 6:14 AM – 5:17 PM
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Weather data by Open-Meteo, updated every 30 minutes.
Postal codes come from the free GeoNames dataset. Where a code is listed with a distance, it belongs to a nearby settlement — GeoNames spells that name differently from ours.
Addresses in O'Fallon fall under 10 postal codes.
Hours in O'Fallon are kept by America/Chicago, standing at UTC−6. Daylight saving observed: No.
The horizon brightens over O'Fallon at 6:43 AM, and the sun sets at 4:48 PM. Daylight runs 10 h 05 min.
The hour in O'Fallon is the hour in Petersburg and Glenview as well.