Chicago (ORD) to Ontario (ONT): On-Time Performance
Data through July 2026
Chicago (ORD) to Ontario (ONT) is a thinner route than most in this dataset — 290 departures over the past year, roughly 6 a week — so treat these numbers as indicative rather than definitive. Of the flights that did operate, 60% arrived on time, noticeably below the national average of 78%.
- On-time
- 60%
- arrived <15 min late
- Avg delay
- 32 min
- completed flights
- Cancelled
- 1.4%
- Flights/day
- 0.79
- last 12 months
- Duration
- 4h 31m
- scheduled
- Distance
- 1,700 mi
Monthly on-time trend
Best time to fly from ORD to ONT
By day of week
| Day | On-time | Avg delay |
|---|---|---|
| Monday | 51% | 36 min |
| Tuesday | 56% | 39 min |
| Wednesday | 66% | 26 min |
| Thursday | 64% | 29 min |
| Friday | 57% | 31 min |
| Saturdaybest | 67% | 31 min |
| Sunday | 58% | 32 min |
What causes delays on this route
Share of total delay minutes by cause, as reported by carriers to the US DOT.
- Late-arriving aircraft56%
- Airline operations25%
- National airspace system15%
- Weather4%
Frequently asked questions
- How often are flights from ORD to ONT delayed?
- 40% of ORD–ONT flights arrived 15 or more minutes late (the US DOT definition of a delay) between 2024-07 and 2026-07. The average arrival delay across completed flights was 32 minutes.
- How long is the flight from ORD to ONT?
- The scheduled ORD–ONT flight time averages 4h 31m over 1,700 miles. Actual arrival times vary — flights on this route land 15+ minutes late 40% of the time.
- How often are ORD to ONT flights cancelled?
- 1.4% of scheduled flights on this route were cancelled between 2024-07 and 2026-07, at or below the national rate of 1.6%.
- What day of the week is most reliable for ORD to ONT?
- Saturday flights have the best record at 67% on-time. Day-of-week differences on this route are meaningful — Monday trails at 51%.
Explore related pages
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Related guides
Based on 361 flights, 2024-07–2026-07. Source: US DOT Bureau of Transportation Statistics. Updated 2026-09-28.