STL (St. Louis) to PDX (Portland) flights arrive on time 69% of the time. The most reliable airline on this route is Southwest Airlines at 71%. The average delay is 37 minutes. Delays on this route are most often caused by the airline (crew, maintenance, or boarding).
Source: Bureau of Transportation Statistics. Updated May 2026.STL → PDX
STL (St. Louis) to PDX (Portland)
STL → PDX on-time performance by month
24
25
JanFebMarAprMayJunJulAugSepOctNovDec
Worse
Better
This route is delayed fairly often. About 69% of flights arrive on schedule.
Delays on this route are most often caused by the airline (crew, maintenance, or boarding).
Accurate?
Accurate?
Good to know
Departing from STL
81% on timeTSA is currently ~24 min. Best time: 4 AM (about 5 min).
Arriving at PDX
83% on timeWhen flights into PDX are late, the average delay is 60 minutes. Build buffer if you have ground plans.
If connecting at PDX: TSA is ~8 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.