SEA (Seattle) to BOS (Boston) flights arrive on time 75% of the time. The most reliable airline on this route is Delta Air Lines at 83%. The average delay is 62 minutes. Delays on this route are most often caused by the airline (crew, maintenance, or boarding).
Source: Bureau of Transportation Statistics. Updated October 2026.SEA → BOS
SEA (Seattle) to BOS (Boston)
SEA → BOS on-time performance by month
24
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JanFebMarAprMayJunJulAugSepOctNovDec
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This route is delayed fairly often. About 75% of flights arrive on schedule.
Delays on this route are most often caused by the airline (crew, maintenance, or boarding).
Accurate?
Delta Air Lines is significantly more reliable on this route at 83% on time vs JetBlue Airways at 63%.
Airline Comparison
Delta Air Lines leads at 83% on time; JetBlue Airways trails at 63%.
Accurate?
Good to know
Departing from SEA
81% on timeExpect ~20 min sitting on the taxiway after your gate pushes back. SEA has long runway queues.
TSA is currently ~23 min. Best time: 4 AM (about 5 min).
Arriving at BOS
77% on timeWhen flights into BOS are late, the average delay is 75 minutes. Build buffer if you have ground plans.
If connecting at BOS: TSA is ~28 min right now. Allow at least 60 minutes for a domestic connection.
Flight cancelled or delayed?
Check what Delta Air Lines owes you — refund rights, action plan, complaint email. Free.
Flying out of SEA? We'll brief you.
Delays, TSA, weather, gates — we'll let you know if something matters.
Know someone flying soon?
Send them the link — delay data, TSA waits, weather, all free.
Data last updated October 2026. Source: Bureau of Transportation Statistics.