IAH (Houston) to STL (St. Louis) flights arrive on time 72% of the time. The most reliable airline on this route is United Airlines at 73%. The average delay is 68 minutes. Delays on this route are most often caused by the incoming plane arriving late.
Source: Bureau of Transportation Statistics. Updated August 2026.IAH → STL
IAH (Houston) to STL (St. Louis)
IAH → STL on-time performance by month
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JanFebMarAprMayJunJulAugSepOctNovDec
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This route is delayed fairly often. About 72% 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 — United Airlines leads slightly at 73% vs SkyWest Airlines at 70%.
Airline Comparison
United Airlines leads at 73% on time; SkyWest Airlines trails at 70%.
Accurate?
Good to know
Departing from IAH
79% on timeExpect ~20 min sitting on the taxiway after your gate pushes back. IAH has long runway queues.
TSA is currently ~5 min. Best time: 4 AM (about 5 min).
Arriving at STL
81% on timeWhen flights into STL are late, the average delay is 66 minutes. Build buffer if you have ground plans.
If connecting at STL: TSA is ~5 min right now. Allow at least 60 minutes for a domestic connection.
Flight cancelled or delayed?
Check what United Airlines owes you — refund rights, action plan, complaint email. Free.
Flying out of IAH? We'll brief you.
Delays, TSA, weather, gates — we'll let you know if something matters.
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Send them the link — delay data, TSA waits, weather, all free.
Data last updated August 2026. Source: Bureau of Transportation Statistics.