IAD (Washington) to DEN (Denver) flights arrive on time 82% of the time. The most reliable airline on this route is Southwest Airlines at 82%. The average delay is 67 minutes. Delays on this route are most often caused by the incoming plane arriving late.
Source: Bureau of Transportation Statistics. Updated March 2026.IAD → DEN
IAD (Washington) to DEN (Denver)
IAD → DEN on-time performance by month
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This route is on time most of the time. About 82% of flights arrive on schedule.
Delays on this route are most often caused by the incoming plane arriving late.
Accurate?
Airlines are roughly equal on this route — Southwest Airlines leads slightly at 82% vs United Airlines at 82%.
Airline Comparison
Southwest Airlines leads at 82% on time; United Airlines trails at 82%.
Accurate?
Good to know
Departing from IAD
83% on timeExpect ~19 min sitting on the taxiway after your gate pushes back. IAD has long runway queues.
TSA is currently ~5 min. Best time: 4 AM (about 5 min).
Arriving at DEN
78% on timeWhen flights into DEN are late, the average delay is 67 minutes. Build buffer if you have ground plans.
If connecting at DEN: TSA is ~9 min right now. Allow at least 60 minutes for a domestic connection.
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Data last updated March 2026. Source: Bureau of Transportation Statistics.