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Round-trip from | £195 |
---|---|
One-way from | £110 |
Popular in | December |
Cheapest in | February |
Average price | £341 |
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Route
Depart
Return
Price
Washington, D.C.Seattle
IAD - SEA
IADSEA
Washington, D.C. Dulles Intl
Wed 13/8
06:30-09:17
Nonstop5h 47m
Seattle/Tacoma Intl
Wed 20/8
16:20-00:20
Nonstop5h 00m
Washington, D.C.Seattle
IAD - SEA
IADSEA
Washington, D.C. Dulles Intl
Tue 12/8
18:13-21:00
Nonstop5h 47m
Seattle/Tacoma Intl
Wed 20/8
16:20-00:20
Nonstop5h 00m
Washington, D.C.Seattle
IAD - SEA
IADSEA
Washington, D.C. Dulles Intl
Tue 9/9
07:35-10:20
Nonstop5h 45m
Seattle/Tacoma Intl
Sat 20/9
21:55-06:01
Nonstop5h 06m
Washington, D.C.Seattle
IAD - SEA
IADSEA
Washington, D.C. Dulles Intl
Wed 13/8
22:06-00:56
Nonstop5h 50m
Seattle/Tacoma Intl
Wed 20/8
23:58-11:28
1 stop8h 30m
Washington, D.C.Seattle
IAD - SEA
IADSEA
Washington, D.C. Dulles Intl
Wed 17/9
05:45-16:55
2 stops14h 10m
Seattle/Tacoma Intl
Wed 24/9
05:15-16:15
1 stop8h 00m
Washington, D.C.Seattle
IAD - SEA
IADSEA
Washington, D.C. Dulles Intl
Sun 9/11
12:50-17:15
1 stop7h 25m
Seattle/Tacoma Intl
Thu 13/11
18:25-10:59
1 stop13h 34m
Washington, D.C.Seattle
IAD - SEA
IADSEA
Washington, D.C. Dulles Intl
Wed 13/8
17:25-23:51
1 stop9h 26m
Washington, D.C.Seattle
IAD - SEA
IADSEA
Washington, D.C. Dulles Intl
Mon 18/8
17:55-20:48
Nonstop5h 53m
Washington, D.C.Seattle
IAD - SEA
IADSEA
Washington, D.C. Dulles Intl
Fri 3/10
18:30-17:01
1 stop25h 31m
Washington, D.C.Seattle
IAD - SEA
IADSEA
Washington, D.C. Dulles Intl
Wed 8/10
17:42-09:20
1 stop18h 38m
The best time to book flights from Washington, D.C. Dulles Intl Airport to Seattle is 58 days before your desired departure date. The cost of your flight will likely increase significantly if you book two weeks in advance of your flight.
Currently, January is the cheapest month in which you can book a flight from Washington, D.C. Dulles Intl Airport to Seattle (average of £622). Flying from Washington, D.C. Dulles Intl Airport to Seattle in July is currently the most expensive (average of £946). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.
When flying from Washington, D.C. Dulles Intl Airport to Seattle, the time of day you decide to fly out makes little to no difference towards the overall price you’ll pay on tickets.
The most flights from IAD to SEA are scheduled on a Thursday (32 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (12 on average).
Overall
Comfort
Boarding
Food
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Entertainment
Reviews
Anonymous,Jul 2025
EUG - SEA
Overall
Comfort
Boarding
Food
Crew
Entertainment
Reviews
Anonymous,Jul 2025
EUG - SEA
Overall
Comfort
Boarding
Food
Crew
Entertainment
Reviews
Anonymous,Jul 2025
EUG - SEA
Overall
Comfort
Boarding
Food
Crew
Entertainment
Reviews
Anonymous,Jul 2025
EUG - SEA
Overall
Comfort
Boarding
Food
Crew
Entertainment
Reviews
Anonymous,Jul 2025
EUG - SEA
Overall
Comfort
Boarding
Food
Crew
Entertainment
Reviews
Anonymous,Jul 2025
EUG - SEA
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