ONT (Ontario) to LAS (Las Vegas) flights arrive on time 79% of the time. The most reliable airline on this route is Southwest Airlines at 80%. The average delay is 77 minutes. Delays on this route are most often caused by the incoming plane arriving late.
Source: Bureau of Transportation Statistics. Updated May 2026.ONT → LAS
ONT (Ontario) to LAS (Las Vegas)
ONT → LAS on-time performance by month
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25
JanFebMarAprMayJunJulAugSepOctNovDec
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This route is on time most of the time. About 79% of flights arrive on schedule.
Delays on this route are most often caused by the incoming plane arriving late.
Accurate?
Airlines are roughly equal on this route — Southwest Airlines leads slightly at 80% vs Frontier Airlines at 77%.
Airline Comparison
Southwest Airlines leads at 80% on time; Frontier Airlines trails at 77%.
Accurate?
Good to know
Departing from ONT
82% on timeTSA is currently ~13 min. Best time: 4 AM (about 5 min).
Arriving at LAS
77% on timeWhen flights into LAS are late, the average delay is 62 minutes. Build buffer if you have ground plans.
If connecting at LAS: TSA is ~15 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.