GSP (Greenville) to IAH (Houston) flights arrive on time 85% of the time. The most reliable airline on this route is United Airlines at 86%. The average delay is 116 minutes. Delays on this route are most often caused by the airline (crew, maintenance, or boarding).
Source: Bureau of Transportation Statistics. Updated March 2026.GSP → IAH
GSP (Greenville) to IAH (Houston)
GSP → IAH on-time performance by month
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JanFebMarAprMayJunJulAugSepOctNovDec
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This route is usually on time. About 85% of flights arrive on schedule.
Delays on this route are most often caused by the airline (crew, maintenance, or boarding).
Accurate?
United Airlines edges out SkyWest Airlines on this route — 86% vs 81% on time.
Airline Comparison
United Airlines leads at 86% on time; SkyWest Airlines trails at 81%.
Accurate?
Good to know
Departing from GSP
83% on timeExpect ~19 min sitting on the taxiway after your gate pushes back. GSP has long runway queues.
TSA is currently ~5 min. Best time: 4 AM (about 5 min).
Arriving at IAH
80% on timeWhen flights into IAH are late, the average delay is 75 minutes. Build buffer if you have ground plans.
If connecting at IAH: 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.