Alaska AirlinesAS60% on time
Flights AS288 07:18 daily · AS279 08:47 Mo Tu Su · AS306 09:03 daily · AS460 15:32 daily
live
Direct flights from Seattle (SEA) to Boston (BOS): 58 nonstop departures observed each week across 2 airlines. 67% of the last 9 tracked flights arrived within 15 minutes of schedule. The median arrival is 5 minutes early. No cancellations were recorded across the 9 tracked flights. The nonstop covers 4,006 km, an estimated 5 hours 38 minutes in the air. Measured by Pro Flight Search from live flight boards at Seattle and Boston. Updated 4 November 2026 at 06:22 UTC.
Today, SEA → BOS
Tue 3 Nov · local times- 07:24 DL459Delta Departed Landed 15:53 −7
- 08:47 AS279Alaska Departed BOS est. 17:10In the air · sched 17:17
- 13:40 DL438Delta Departed Landed 22:51 +41
- 15:36 AS460Alaska Departed Landed 23:50 −8
- 21:20 AS214Alaska Departed BOS est. 05:44In the air · sched 05:40
- 23:10 DL473Delta On scheduleGate S9A BOS est. 07:42 +7sched 07:35
Checked SEA board 22:22 · BOS board 01:09
SEA
Seattle
smooth · +11
BOS
Boston
smooth · +0
4,006 km · ~5h 38m est.
Runs mixed · 2 airlines · 58x weekly · nonstop
67% on time
of the last 9 tracked SEA → BOS flights arrived within 15 minutes
Median arrival delay is −5 min. 0 of 9 tracked legs cancelled in the sample. Will a delayed flight be cancelled? →
Median arrival−5 minacross the last 9 arrivals
Flight time~5h 38mestimated from route distance
Weekly departures58x2 direct airlines on the leg
The week
scheduled departures · origin local time06121824
Mon
Tue
Wed
Thu
Fri
Sat
Sun
Alaska AirlinesDelta Air Lines
Each mark is a scheduled departure at its origin-local time, observed operating in the last 7 days. Today is highlighted.
Who flies it
observed on the boards · 7 daysHistory
operated legs · board outcomesActual board outcomes rather than schedules, paired departure and arrival per flight and day.
Full board history, day by day →
Airports right now
live boardsWeather lens
Conditions are tightest at BOS: a 37% chance of a 15+ minute delay. In this weather, the more delayed of the two airports is typically about +5 min. Both figures come from the two airports' delay records in similar weather. See live delays → · Weather risk by airport →
next sweep in 120s
How the Seattle to Boston route actually runs
Pro Flight Search records official board updates for nonstop SEA to BOS flights through the day: schedules, estimates, gate pushes and actual departures. The verdict above comes from operated flights, so it reflects what this route does rather than what the timetable promises.
Planning around a delay? Live airport delays · Weather delay risk map · Will a delayed flight be cancelled? · Do planes make up time in the air? · How we measure
Cite this data
Journalists, bloggers, and researchers may cite this page with attribution and a link to Pro Flight Search.
Suggested citation
Pro Flight Search: Seattle (SEA) to Boston (BOS) route reliability, measured from operated flights on official airport boards.
Canonical URL
How we measure this →
https://proflightsearch.com/search-flights/SEA-BOS
SEA to BOS questions
Is SEA–BOS running on time right now?
Smooth skies ahead. The departure side at SEA is the weaker end, route health score 92/100. The airports section above carries the live status and delay window at both ends.
Morning or evening flight on SEA–BOS?
Operators schedule morning departures around 07:18 and evening departures around 23:00 from SEA. Earlier flights typically land before destination-airport delays accumulate later in the day; check the BOS delay card to confirm conditions when you'd arrive.
How long is the flight from SEA to BOS?
Great-circle distance is 4,006 km. With typical jet cruise speed plus taxi, climb and descent, expect roughly 313–373 min gate-to-gate on this route.
How often does SEA–BOS fly?
2 carriers operate this route, around 58 flights a week between them. Compare carrier days and times in the airline list above.
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