ONT → DEN: cancellations & delays
Over Jan 2023 - Apr 2026, 0.9% of Ontario International Airport (ONT) to Denver International Airport (DEN) flights were cancelled and 17.8% arrived at least 15 minutes late, across 9,202 flights, flown by WN, UA, F9, OO. Cancellations peak in August.
Check today's live ONT departures →Airport pages: Ontario International Airport (ONT) · Denver International Airport (DEN)
Rates are historical averages from U.S. DOT (BTS) on-time records; a specific flight's live estimate can differ with weather and the day's disruptions.