Koster in numbers
- Coordinates
- 41.0917, -87.6850
- Elevation
- 193 m above sea level
- Region
- Illinois
- Country
- United States, North America
- Capital
- Washington, D.C. — 939 km away
- Same name
- 4 more places in the world share this name
The page gives the present local time in Koster, Illinois, United States, whose time zone is America/Chicago (−6).
Koster, United States
Sunday, 8 November 2026
UTC−6 · America/Chicago
Local time in Koster
UTC−6 · no daylight saving time
Local time in Koster, Illinois.
Sunrise 6:31 AM Solar noon 11:36 AM Sunset 4:40 PM Daylight 10 h 09 min Night 13 h 51 min Civil twilight 6:02 AM – 5:09 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.
Koster includes 4 postal codes.
Koster sets its clocks by America/Chicago, which runs UTC−6. Daylight saving time here: No.
Sunrise comes to Koster at 6:31 AM and sunset at 4:40 PM today. Together that makes 10 h 09 min of light.
The same local time applies in Koster, Collins (historical) and Wichert.