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 65 minutes. Delays on this route are most often caused by the incoming plane arriving late.
Source: Bureau of Transportation Statistics. Updated March 2026.STL → ATL
STL (St. Louis) to ATL (Atlanta)
STL → ATL on-time performance by month
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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 72%.
Airline Comparison
Delta Air Lines leads at 89% on time; Frontier Airlines trails at 72%.
Accurate?
Good to know
Departing from STL
81% on timeTSA is currently ~5 min. Best time: 4 AM (about 5 min).
Arriving at ATL
83% on timeWhen flights into ATL are late, the average delay is 68 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.
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Check what Delta Air Lines owes you — refund rights, action plan, complaint email. Free.
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Data last updated March 2026. Source: Bureau of Transportation Statistics.