Frontier AirlinesF9
live
Direct flights from Denver (DEN) to Ontario (ONT): 21 nonstop departures observed each week across 3 airlines. 73% of the last 11 operated flights arrived within 15 minutes of schedule. The median arrival is 8 minutes early. No cancellations were recorded across the 11 tracked flights. The nonstop covers 1,316 km, an estimated 2 hours 11 minutes in the air. Measured by Pro Flight Search from live flight boards at Denver and Ontario. Updated 10 September 2026 at 20:38 UTC.
DEN
Denver
smooth · +3
ONT
Ontario
smooth · +0
1,316 km · ~2h 11m est.
Runs mixed · 3 airlines · 21x weekly · nonstop
73% on time
of the last 11 operated DEN → ONT flights arrived within 15 minutes
Median arrival delay is −8 min. 0 of 11 tracked legs cancelled in the sample. Will a delayed flight be cancelled? →
Median arrival−8 minacross the last 11 operated legs
Flight time~2h 11mestimated from route distance
Weekly departures21x3 direct airlines on the leg
Cancelled0.0%recent route rate · 0 of 11
The week
scheduled departures · origin local time06121824
Mon
Tue
Wed
Thu
Fri
Sat
Sun
Frontier AirlinesSouthwest AirlinesUnited Airlines
Each mark is a scheduled departure at its origin-local time, observed operating in the last 7 days. Today is highlighted.
Who flies it
observed on the boards · 7 daysHistory
operated legs · board outcomes09-09UA2028dep +28 → arr+13
Actual board outcomes rather than schedules, paired departure and arrival per flight and day.
Full board history, day by day →
Airports right now
live boardsWeather lens
Current conditions put the pressure at DEN and ONT: 43% odds of a 15+ minute delay and around +9 min expected when it bites, measured from this route's own weather-matched delay history. See live delays → · Weather risk by airport →
next sweep in 120s
How the Denver to Ontario route actually runs
Pro Flight Search records official board updates for nonstop DEN to ONT flights through the day: schedules, estimates, gate pushes and actual departures. The verdict above comes from operated flights, so it reflects what this route does rather than what the timetable promises.
Planning around a delay? Live airport delays · Weather delay risk map · Will a delayed flight be cancelled? · Do planes make up time in the air? · How we measure
Cite this data
Journalists, bloggers, and researchers may cite this page with attribution and a link to Pro Flight Search.
Suggested citation
Pro Flight Search — Denver (DEN) to Ontario (ONT) route reliability, measured from operated flights on official airport boards.
Canonical URL
How we measure this →
https://proflightsearch.com/search-flights/DEN-ONT
DEN to ONT questions
Is DEN–ONT running on time right now?
Smooth skies ahead. The departure side at DEN is the weaker end, route health score 96/100. The airports section above carries the live status and delay window at both ends.
Morning or evening flight on DEN–ONT?
Operators schedule morning departures around 08:45 and evening departures around 17:50 from DEN. Earlier flights typically land before destination-airport delays accumulate later in the day; check the ONT delay card to confirm conditions when you'd arrive.
How long is the flight from DEN to ONT?
Great-circle distance is 1,316 km. With typical jet cruise speed plus taxi, climb and descent, expect roughly 123–143 min gate-to-gate on this route.
How often does DEN–ONT fly?
3 carriers operate this route, around 45 flights a week between them. Compare carrier days and times in the airline list above.
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