SJC (San Jose) to ONT (Ontario) flights arrive on time 86% of the time. The most reliable airline on this route is Southwest Airlines at 86%. The average delay is 52 minutes. Delays on this route are most often caused by the incoming plane arriving late.
Source: Bureau of Transportation Statistics. Updated May 2026.SJC → ONT
SJC (San Jose) to ONT (Ontario)
SJC → ONT on-time performance by month
24
25
JanFebMarAprMayJunJulAugSepOctNovDec
Worse
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This route is usually on time. About 86% of flights arrive on schedule.
Delays on this route are most often caused by the incoming plane arriving late.
Accurate?
Accurate?
Good to know
Departing from SJC
84% on timeTSA is currently ~16 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.