Chicago to Ontario time converter
Ontario is 1 hour ahead of Chicago. When it is 9:00 AM in Chicago, it is 10:00 AM in Ontario.
4:21 PM in Chicago, Sunday, October 18, 2026
Shared working hours (9:00–18:00)
Chicago to Ontario conversion table
Every hour of today in Chicago and the matching time in Ontario. Light rows are typical working hours (9:00–18:00).
| Chicago | Ontario |
|---|---|
| 12:00 AM | 1:00 AM |
| 1:00 AM | 2:00 AM |
| 2:00 AM | 3:00 AM |
| 3:00 AM | 4:00 AM |
| 4:00 AM | 5:00 AM |
| 5:00 AM | 6:00 AM |
| 6:00 AM | 7:00 AM |
| 7:00 AM | 8:00 AM |
| 8:00 AM | 9:00 AM |
| 9:00 AM | 10:00 AM |
| 10:00 AM | 11:00 AM |
| 11:00 AM | 12:00 PM |
| 12:00 PM | 1:00 PM |
| 1:00 PM | 2:00 PM |
| 2:00 PM | 3:00 PM |
| 3:00 PM | 4:00 PM |
| 4:00 PM | 5:00 PM |
| 5:00 PM | 6:00 PM |
| 6:00 PM | 7:00 PM |
| 7:00 PM | 8:00 PM |
| 8:00 PM | 9:00 PM |
| 9:00 PM | 10:00 PM |
| 10:00 PM | 11:00 PM |
| 11:00 PM | 12:00 AM+1 day |
Best time to call or meet
Both sides are at work from 9:00 AM – 5:00 PM in Chicago (10:00 AM – 6:00 PM in Ontario).
Daylight saving time and the difference
The difference changes during the year because Chicago and Ontario switch clocks on different dates:
- Oct 18, 2026 – Nov 1, 2026: +1h
- Nov 1, 2026 – Nov 1, 2026: ±0
- Nov 1, 2026 – Mar 14, 2027: +1h
- Mar 14, 2027 – Mar 14, 2027: +2h
- Mar 14, 2027 – Oct 18, 2027: +1h
More conversions
Questions and answers
What is the time difference between Chicago and Ontario?
Ontario is 1 hour ahead of Chicago.
What time is it in Ontario when it is 9 AM in Chicago?
When it is 9:00 AM in Chicago, it is 10:00 AM in Ontario.
When is the best time to call Ontario from Chicago?
Both sides are at work from 9:00 AM – 5:00 PM in Chicago (10:00 AM – 6:00 PM in Ontario).
Does the time difference between Chicago and Ontario change?
Yes, for part of the year, because daylight saving time starts and ends on different dates or applies on one side only.