STL (St. Louis) to IAH (Houston) flights arrive on time 78% of the time. The most reliable airline on this route is United Airlines at 78%. The average delay is 82 minutes. Delays on this route are most often caused by the airline (crew, maintenance, or boarding).
Source: Bureau of Transportation Statistics. Updated October 2026.STL → IAH
STL (St. Louis) to IAH (Houston)
STL → IAH on-time performance by month
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JanFebMarAprMayJunJulAugSepOctNovDec
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This route is on time most of the time. About 78% of flights arrive on schedule.
Delays on this route are most often caused by the airline (crew, maintenance, or boarding).
Accurate?
Airlines are roughly equal on this route — United Airlines leads slightly at 78% vs SkyWest Airlines at 77%.
Airline Comparison
United Airlines leads at 78% on time; SkyWest Airlines trails at 77%.
Accurate?
Good to know
Departing from STL
80% on timeTSA is currently ~30 min. Best time: 4 AM (about 5 min).
Arriving at IAH
79% on timeWhen flights into IAH are late, the average delay is 76 minutes. Build buffer if you have ground plans.
If connecting at IAH: TSA is ~24 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 STL? We'll brief you.
Delays, TSA, weather, gates — we'll let you know if something matters.
Know someone flying soon?
Send them the link — delay data, TSA waits, weather, all free.
Data last updated October 2026. Source: Bureau of Transportation Statistics.