STL (St. Louis) to ATL (Atlanta) flights arrive on time 86% of the time. The most reliable airline on this route is Delta Air Lines at 89%. The average delay is 69 minutes. Delays on this route are most often caused by the incoming plane arriving late.
Source: Bureau of Transportation Statistics. Updated August 2026.STL → ATL
STL (St. Louis) to ATL (Atlanta)
STL → ATL on-time performance by month
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JanFebMarAprMayJunJulAugSepOctNovDec
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This route is usually on time. About 86% of flights arrive on schedule.
Delays on this route are most often caused by the incoming plane arriving late.
Accurate?
Delta Air Lines is significantly more reliable on this route at 89% on time vs Frontier Airlines at 65%.
Airline Comparison
Delta Air Lines leads at 89% on time; Frontier Airlines trails at 65%.
Accurate?
Good to know
Departing from STL
81% on timeTSA is currently ~5 min. Best time: 4 AM (about 5 min).
Arriving at ATL
80% on timeWhen flights into ATL are late, the average delay is 72 minutes. Build buffer if you have ground plans.
If connecting at ATL: TSA is ~5 min right now. Allow at least 60 minutes for a domestic connection.
Flight cancelled or delayed?
Check what Delta Air Lines 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 August 2026. Source: Bureau of Transportation Statistics.