Ontario (ONT) to Chicago (ORD): On-Time Performance
Data through May 2026
Ontario (ONT) to Chicago (ORD) is a thinner route than most in this dataset — 291 departures over the past year, roughly 6 a week — so treat these numbers as indicative rather than definitive. Of the flights that did operate, 79% arrived on time.
- On-time
- 79%
- arrived <15 min late
- Avg delay
- 17 min
- completed flights
- Cancelled
- 0.7%
- Flights/day
- 0.80
- last 12 months
- Duration
- 4h 2m
- scheduled
- Distance
- 1,700 mi
Monthly on-time trend
Best time to fly from ONT to ORD
By day of week
| Day | On-time | Avg delay |
|---|---|---|
| Monday | 88% | 13 min |
| Tuesday | 73% | 23 min |
| Wednesdaybest | 90% | 19 min |
| Thursday | 77% | 11 min |
| Friday | 76% | 14 min |
| Saturday | 82% | 20 min |
| Sunday | 66% | 18 min |
What causes delays on this route
Share of total delay minutes by cause, as reported by carriers to the US DOT.
- Late-arriving aircraft18%
- Airline operations42%
- National airspace system41%
Frequently asked questions
- How often are flights from ONT to ORD delayed?
- 21% of ONT–ORD flights arrived 15 or more minutes late (the US DOT definition of a delay) between 2024-06 and 2026-05. The average arrival delay across completed flights was 17 minutes.
- How long is the flight from ONT to ORD?
- The scheduled ONT–ORD flight time averages 4h 2m over 1,700 miles. Actual arrival times vary — flights on this route land 15+ minutes late 21% of the time.
- How often are ONT to ORD flights cancelled?
- 0.7% of scheduled flights on this route were cancelled between 2024-06 and 2026-05, at or below the national rate of 1.6%.
- What day of the week is most reliable for ONT to ORD?
- Wednesday flights have the best record at 90% on-time. Day-of-week differences on this route are meaningful — Sunday trails at 66%.
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Based on 301 flights, 2024-06–2026-05. Source: US DOT Bureau of Transportation Statistics. Updated 2026-07-01.