Alaska AirlinesAS67% on time
Flights AS1574 07:00 daily · AS375 09:03 daily · AS737 varies daily
live
Direct flights from Washington (IAD) to Seattle (SEA): 21 nonstop departures observed each week across 3 airlines. 60% of the last 10 operated flights arrived within 15 minutes of schedule. The median arrival is 15 minutes late. No cancellations were recorded across the 10 tracked flights. The nonstop covers 3,702 km, an estimated 5 hours 15 minutes in the air. Measured by Pro Flight Search from live flight boards at Washington and Seattle. Updated 14 September 2026 at 09:23 UTC.
IAD
Washington
disrupted · +79
SEA
Seattle
busy · +21
3,702 km · ~5h 15m est.
Runs mixed · 3 airlines · 21x weekly · nonstop
60% on time
of the last 10 operated IAD → SEA flights arrived within 15 minutes
Median arrival delay is +15 min. 0 of 10 tracked legs cancelled in the sample. Will a delayed flight be cancelled? →
Median arrival+15 minacross the last 10 operated legs
Flight time~5h 15mestimated from route distance
Weekly departures21x3 direct airlines on the leg
Cancelled0.0%recent route rate · 0 of 10
The week
scheduled departures · origin local time06121824
Mon
Tue
Wed
Thu
Fri
Sat
Sun
Alaska AirlinesDelta Air LinesUnited Airlines
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
Current conditions put the pressure at IAD and SEA: 35% odds of a 15+ minute delay and around +2 min expected when it bites, measured from this route's own weather-matched delay history. See live delays → · Weather risk by airport →
next sweep in 120s
How the Washington to Seattle route actually runs
Pro Flight Search records official board updates for nonstop IAD to SEA 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 — Washington (IAD) to Seattle (SEA) route reliability, measured from operated flights on official airport boards.
Canonical URL
How we measure this →
https://proflightsearch.com/search-flights/IAD-SEA
IAD to SEA questions
Is IAD–SEA running on time right now?
Significant delay risk. The departure side at IAD is the weaker end, route health score 36/100. The airports section above carries the live status and delay window at both ends.
Morning or evening flight on IAD–SEA?
Operators schedule morning departures around 07:00 from IAD. Earlier flights typically land before destination-airport delays accumulate later in the day; check the SEA delay card to confirm conditions when you'd arrive.
How long is the flight from IAD to SEA?
Great-circle distance is 3,702 km. With typical jet cruise speed plus taxi, climb and descent, expect roughly 291–347 min gate-to-gate on this route.
How often does IAD–SEA fly?
3 carriers operate this route, around 41 flights a week between them. Compare carrier days and times in the airline list above.
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