BOS (Boston) to STL (St. Louis) flights arrive on time 81% of the time. The most reliable airline on this route is Republic Airways at 94%. 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 May 2026.BOS → STL
BOS (Boston) to STL (St. Louis)
BOS → STL on-time performance by month
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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 94% on time vs Southwest Airlines at 79%.
Airline Comparison
Republic Airways leads at 94% on time; Southwest Airlines trails at 79%.
Accurate?
Good to know
Departing from BOS
79% on timeExpect ~19 min sitting on the taxiway after your gate pushes back. BOS has long runway queues.
TSA is currently ~21 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 ~24 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.