STL (St. Louis) to ORD (Chicago) flights arrive on time 76% of the time. The most reliable airline on this route is Republic Airways at 83%. The average delay is 90 minutes. Delays on this route are most often caused by the airline (crew, maintenance, or boarding).
Source: Bureau of Transportation Statistics. Updated March 2026.STL → ORD
STL (St. Louis) to ORD (Chicago)
STL → ORD on-time performance by month
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JanFebMarAprMayJunJulAugSepOctNovDec
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This route is on time most of the time. About 76% of flights arrive on schedule.
Delays on this route are most often caused by the airline (crew, maintenance, or boarding).
Accurate?
Republic Airways is significantly more reliable on this route at 83% on time vs United Airlines at 65%.
Airline Comparison
Republic Airways leads at 83% on time; United Airlines trails at 65%.
Accurate?
Good to know
Departing from STL
81% on timeTSA is currently ~20 min. Best time: 4 AM (about 5 min).
Arriving at ORD
80% on timeWhen flights into ORD are late, the average delay is 76 minutes. Build buffer if you have ground plans.
If connecting at ORD: TSA is ~10 min right now. Allow at least 60 minutes for a domestic connection.
Flight cancelled or delayed?
Check what Republic Airways owes you — refund rights, action plan, complaint email. Free.
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Data last updated March 2026. Source: Bureau of Transportation Statistics.