ONT → SFO: cancellations & delays
Over Jan 2023 - Apr 2026, 1.3% of Ontario International Airport (ONT) to San Francisco International Airport (SFO) flights were cancelled and 25.3% arrived at least 15 minutes late, across 4,655 flights, flown by OO, UA, F9. Cancellations peak in February.
Check today's live ONT departures →Airport pages: Ontario International Airport (ONT) · San Francisco International Airport (SFO)
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.