For a smooth check-in at IAD, locate your airline’s counter by walking around the first row if not visible initially.
Round-trip from | $257 (American Airlines) |
---|---|
One-way from | $148 (Alaska Airlines) |
Popular in | December |
Cheapest in | February |
Average price | $457 |
Good round-trip deal | $364 or less |
Good one-way deal | $201 or less |
Fly from
Fly to
Route
Depart
Return
Price
Washington, D.C.Seattle
IAD - SEA
IADSEA
Washington, D.C. Dulles Intl
Wed 9/3
2:21 pm-10:29 pm
1 stop11h 08m
Seattle/Tacoma Intl
Tue 9/9
5:26 am-4:50 pm
1 stop8h 24m
Washington, D.C.Seattle
IAD - SEA
IADSEA
Washington, D.C. Dulles Intl
Wed 8/13
6:30 am-9:17 am
Nonstop5h 47m
Seattle/Tacoma Intl
Wed 8/20
4:20 pm-12:20 am
Nonstop5h 00m
Washington, D.C.Seattle
IAD - SEA
IADSEA
Washington, D.C. Dulles Intl
Sat 8/30
9:00 am-11:43 am
Nonstop5h 43m
Seattle/Tacoma Intl
Sat 9/6
11:30 pm-7:33 am
Nonstop5h 03m
Washington, D.C.Seattle
IAD - SEA
IADSEA
Washington, D.C. Dulles Intl
Mon 8/11
7:30 am-2:06 pm
1 stop9h 36m
Seattle/Tacoma Intl
Thu 8/14
3:11 pm-6:34 am
1 stop12h 23m
Washington, D.C.Seattle
IAD - SEA
IADSEA
Washington, D.C. Dulles Intl
Wed 8/13
1:05 pm-3:53 pm
Nonstop5h 48m
Seattle/Tacoma Intl
Tue 8/19
5:35 pm-5:24 am
1 stop8h 49m
Washington, D.C.Seattle
IAD - SEA
IADSEA
Washington, D.C. Dulles Intl
Thu 10/16
11:52 am-5:25 pm
1 stop8h 33m
Seattle/Tacoma Intl
Sun 10/19
11:59 pm-11:26 am
1 stop8h 27m
Washington, D.C.Seattle
IAD - SEA
IADSEA
Washington, D.C. Dulles Intl
Sat 9/13
1:00 pm-10:07 pm
1 stop12h 07m
Seattle/Tacoma Intl
Tue 9/30
9:55 pm-6:01 am
Nonstop5h 06m
Washington, D.C.Seattle
IAD - SEA
IADSEA
Washington, D.C. Dulles Intl
Sat 8/30
5:05 pm-9:50 pm
1 stop7h 45m
Seattle/Tacoma Intl
Sat 9/20
7:35 am-10:45 pm
2 stops12h 10m
Washington, D.C.Seattle
IAD - SEA
IADSEA
Washington, D.C. Dulles Intl
Wed 8/13
8:10 am-4:54 pm
1 stop11h 44m
Washington, D.C.Seattle
IAD - SEA
IADSEA
Washington, D.C. Dulles Intl
Mon 8/18
7:35 am-10:20 am
Nonstop5h 45m
The price you pay for your flight from Washington, D.C. Dulles Intl Airport to Seattle may vary depending on when you book. For the best chance of a lower fare, look to book 58 days in advance of your trip. Fares are likely to increase a fortnight or so before your departure date.
Currently, January is the cheapest month in which you can book a flight from Washington, D.C. Dulles Intl Airport to Seattle (average of $238). Flying from Washington, D.C. Dulles Intl Airport to Seattle in June is currently the most expensive (average of $388). 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.
One of the essential ways to save on airfare from Washington, D.C. Dulles Intl Airport to Seattle is to remain as flexible as possible. Flights that are in the morning tend to be the most expensive. A flight in the evening could potentially save you up to 18% on airfare.
Travelers seeking maximum savings on their Washington, D.C. Dulles Intl Airport to Seattle flight should consider departing on Thursday evenings when fares are most often at their lowest. Sunday mornings flights should be avoided if possible as fares are typically the most expensive at this time.
The most flights from IAD to SEA are scheduled on a Thursday (31 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (11 on average).
Boarding
Comfort
Food
Entertainment
Crew
Overall
Reviews
Anonymous,Jul 2025
EUG - SEA
Boarding
Comfort
Food
Entertainment
Crew
Overall
Reviews
Anonymous,Jul 2025
EUG - SEA
Boarding
Comfort
Food
Entertainment
Crew
Overall
Reviews
Anonymous,Jul 2025
EUG - SEA
Boarding
Comfort
Food
Entertainment
Crew
Overall
Reviews
Anonymous,Jul 2025
EUG - SEA
Boarding
Comfort
Food
Entertainment
Crew
Overall
Reviews
Anonymous,Jul 2025
EUG - SEA
Boarding
Comfort
Food
Entertainment
Crew
Overall
Reviews
Anonymous,Jul 2025
EUG - SEA
Airline | Cheapest | Average | Flexibility | On-time |
---|---|---|---|---|
Cheapest$111 | Average$240 | FlexibilityNo cancel fee | On-time62% | |
Cheapest$144 | Average$370 | FlexibilityNo cancel fee | On-time83% | |
Cheapest$168 | Average$391 | FlexibilityNo cancel fee | On-time85% | |
Cheapest$218 | Average$382 | FlexibilityNo cancel fee | On-timeN/A | |
Cheapest$263 | Average$426 | FlexibilityNo cancel fee | On-time75% | |
Cheapest$284 | Average$470 | FlexibilityNo cancel fee | On-time69% | |
Cheapest$297 | Average$522 | FlexibilityNo cancel fee | On-time71% |