IAH (Houston) to SEA (Seattle) flights arrive on time 76% of the time. The most reliable airline on this route is Alaska Airlines at 77%. The average delay is 60 minutes. Delays on this route are most often caused by the incoming plane arriving late.
Source: Bureau of Transportation Statistics. Updated April 2026.IAH → SEA
IAH (Houston) to SEA (Seattle)
IAH → SEA on-time performance by month
24
25
JanFebMarAprMayJunJulAugSepOctNovDec
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This route is on time most of the time. About 76% 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 — Alaska Airlines leads slightly at 77% vs United Airlines at 77%.
Airline Comparison
Alaska Airlines leads at 77% on time; United Airlines trails at 77%.
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 ~25 min. Best time: 4 AM (about 5 min).
Arriving at SEA
82% on timeWhen flights into SEA are late, the average delay is 57 minutes. Build buffer if you have ground plans.
If connecting at SEA: TSA is ~15 min right now. Allow at least 60 minutes for a domestic connection.
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Data last updated April 2026. Source: Bureau of Transportation Statistics.