SFO (San Francisco) to ONT (Ontario) flights arrive on time 81% of the time. The most reliable airline on this route is SkyWest Airlines at 84%. The average delay is 71 minutes. Delays on this route are most often caused by the incoming plane arriving late.
Source: Bureau of Transportation Statistics. Updated May 2026.SFO → ONT
SFO (San Francisco) to ONT (Ontario)
SFO → ONT on-time performance by month
24
25
JanFebMarAprMayJunJulAugSepOctNovDec
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This route is on time most of the time. About 81% of flights arrive on schedule.
Delays on this route are most often caused by the incoming plane arriving late.
Accurate?
SkyWest Airlines is significantly more reliable on this route at 84% on time vs Frontier Airlines at 67%.
Airline Comparison
SkyWest Airlines leads at 84% on time; Frontier Airlines trails at 67%.
Accurate?
Good to know
Departing from SFO
80% on timeExpect ~20 min sitting on the taxiway after your gate pushes back. SFO has long runway queues.
TSA is currently ~21 min. Best time: 4 AM (about 5 min).
Arriving at ONT
82% on timeWhen flights into ONT are late, the average delay is 63 minutes. Build buffer if you have ground plans.
If connecting at ONT: TSA is ~13 min right now. Allow at least 60 minutes for a domestic connection.
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Data last updated May 2026. Source: Bureau of Transportation Statistics.