SEA (Seattle) to MIA (Miami) flights arrive on time 80% of the time. The most reliable airline on this route is American Airlines at 82%. The average delay is 58 minutes. Delays on this route are most often caused by air traffic and busy airspace.
Source: Bureau of Transportation Statistics. Updated March 2026.SEA → MIA
SEA (Seattle) to MIA (Miami)
SEA → MIA on-time performance by month
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This route is on time most of the time. About 80% of flights arrive on schedule.
Delays on this route are most often caused by air traffic and busy airspace.
Accurate?
Airlines are roughly equal on this route — American Airlines leads slightly at 82% vs Alaska Airlines at 78%.
Airline Comparison
American Airlines leads at 82% on time; Alaska Airlines trails at 78%.
Accurate?
Good to know
Departing from SEA
82% on timeExpect ~19 min sitting on the taxiway after your gate pushes back. SEA has long runway queues.
TSA is currently ~5 min. Best time: 4 AM (about 5 min).
Arriving at MIA
76% on timeWhen flights into MIA are late, the average delay is 75 minutes. Build buffer if you have ground plans.
If connecting at MIA: TSA is ~5 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.