IAH (Houston) to STL (St. Louis) flights arrive on time 72% of the time. The most reliable airline on this route is SkyWest Airlines at 74%. 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 March 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 — SkyWest Airlines leads slightly at 74% vs United Airlines at 71%.
Airline Comparison
SkyWest Airlines leads at 74% on time; United Airlines trails at 71%.
Accurate?
Good to know
Departing from IAH
80% on timeExpect ~18 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 63 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.
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Data last updated March 2026. Source: Bureau of Transportation Statistics.