BOS (Boston) to SEA (Seattle) flights arrive on time 75% of the time. The most reliable airline on this route is JetBlue Airways at 78%. The average delay is 57 minutes. Delays on this route are most often caused by the incoming plane arriving late.
Source: Bureau of Transportation Statistics. Updated July 2026.BOS → SEA
BOS (Boston) to SEA (Seattle)
BOS → SEA on-time performance by month
24
25
26
JanFebMarAprMayJunJulAugSepOctNovDec
Worse
Better
This route is delayed fairly often. About 75% of flights arrive on schedule.
Delays on this route are most often caused by the incoming plane arriving late.
Accurate?
JetBlue Airways edges out Alaska Airlines on this route — 78% vs 73% on time.
Airline Comparison
JetBlue Airways leads at 78% on time; Alaska Airlines trails at 73%.
Accurate?
Good to know
Departing from BOS
77% on timeExpect ~21 min sitting on the taxiway after your gate pushes back. BOS has long runway queues.
TSA is currently ~6 min. Best time: 4 AM (about 5 min).
Arriving at SEA
80% on timeWhen flights into SEA are late, the average delay is 57 minutes. Build buffer if you have ground plans.
If connecting at SEA: TSA is ~12 min right now. Allow at least 60 minutes for a domestic connection.
Flight cancelled or delayed?
Check what JetBlue Airways owes you — refund rights, action plan, complaint email. Free.
Flying out of BOS? 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 July 2026. Source: Bureau of Transportation Statistics.