STL (St. Louis) to PHL (Philadelphia) flights arrive on time 81% of the time. The most reliable airline on this route is Republic Airways at 90%. The average delay is 82 minutes. Delays on this route are most often caused by the incoming plane arriving late.
Source: Bureau of Transportation Statistics. Updated May 2026.STL → PHL
STL (St. Louis) to PHL (Philadelphia)
STL → PHL on-time performance by month
24
25
JanFebMarAprMayJunJulAugSepOctNovDec
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This route is on time most of the time. About 81% of flights arrive on schedule.
Delays on this route are most often caused by the incoming plane arriving late.
Accurate?
Republic Airways is significantly more reliable on this route at 90% on time vs Frontier Airlines at 58%.
Airline Comparison
Republic Airways leads at 90% on time; Frontier Airlines trails at 58%.
Accurate?
Good to know
Departing from STL
81% on timeTSA is currently ~24 min. Best time: 4 AM (about 5 min).
Arriving at PHL
79% on timeWhen flights into PHL are late, the average delay is 79 minutes. Build buffer if you have ground plans.
If connecting at PHL: TSA is ~31 min right now. Allow at least 60 minutes for a domestic connection.
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Data last updated May 2026. Source: Bureau of Transportation Statistics.