
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $322 (CheapOair) |
One-way from | $173 (United Airlines) |
Popular in | June |
Cheapest in | January |
Average price | $546 |
Good round-trip deal | $385 or less |
Good one-way deal | $244 or less |
Fly from
Fly to
Route
Depart
Return
Washington, D.C.Seattle
IAD - SEA
IADSEA
Washington, D.C. Dulles Intl
Sat 8/15
6:03 am-8:48 am
Nonstop5h 45m
Seattle/Tacoma Intl
Mon 8/24
9:35 pm-5:40 am
Nonstop5h 05m
Washington, D.C.Seattle
IAD - SEA
IADSEA
Washington, D.C. Dulles Intl
Thu 8/6
7:53 pm-9:19 am
1 stop16h 26m
Seattle/Tacoma Intl
Fri 8/14
10:43 pm-6:39 am
Nonstop4h 56m
Washington, D.C.Seattle
IAD - SEA
IADSEA
Washington, D.C. Dulles Intl
Fri 7/3
5:55 pm-8:46 pm
Nonstop5h 51m
Seattle/Tacoma Intl
Wed 7/8
8:15 am-4:24 pm
Nonstop5h 09m
Washington, D.C.Seattle
IAD - SEA
IADSEA
Washington, D.C. Dulles Intl
Tue 8/4
5:55 pm-8:46 pm
Nonstop5h 51m
Seattle/Tacoma Intl
Wed 8/12
1:57 pm-12:44 am
1 stop7h 47m
Washington, D.C.Seattle
IAD - SEA
IADSEA
Washington, D.C. Dulles Intl
Wed 7/22
6:14 pm-9:09 pm
Nonstop5h 55m
Seattle/Tacoma Intl
Thu 7/30
4:01 pm-11:59 pm
Nonstop4h 58m
Washington, D.C.Seattle
IAD - SEA
IADSEA
Washington, D.C. Dulles Intl
Tue 8/11
7:10 am-9:55 am
Nonstop5h 45m
Seattle/Tacoma Intl
Wed 8/19
5:30 am-4:38 pm
1 stop8h 08m
Washington, D.C.Seattle
IAD - SEA
IADSEA
Washington, D.C. Dulles Intl
Sun 7/19
6:03 am-8:48 am
Nonstop5h 45m
Seattle/Tacoma Intl
Wed 7/29
6:21 am-6:45 pm
1 stop9h 24m
Washington, D.C.Seattle
IAD - SEA
IADSEA
Washington, D.C. Dulles Intl
Tue 8/4
5:55 pm-8:46 pm
Nonstop5h 51m
Seattle/Tacoma Intl
Tue 8/18
1:57 pm-12:44 am
1 stop7h 47m
Washington, D.C.Seattle
IAD - SEA
IADSEA
Washington, D.C. Dulles Intl
Mon 8/3
9:30 am-12:16 pm
Nonstop5h 46m
Seattle/Tacoma Intl
Thu 8/13
10:43 pm-6:39 am
Nonstop4h 56m
Washington, D.C.Seattle
IAD - SEA
IADSEA
Washington, D.C. Dulles Intl
Tue 8/25
8:31 am-8:43 pm
2 stops15h 12m
Seattle/Tacoma Intl
Wed 8/26
11:00 pm-11:52 am
1 stop9h 52m
| Provider | Price Accuracy | Trust Score* |
|---|---|---|
| Price Accuracy1 star | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*3 stars | |
| Price Accuracy1 star | Trust Score*3 stars | |
| Price Accuracy- | Trust Score*1 star |
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 52 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 $231). Flying from Washington, D.C. Dulles Intl Airport to Seattle in June is currently the most expensive (average of $546). 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 evening tend to be the most expensive. A flight at noon could potentially save you up to 16% on airfare.
Travelers seeking maximum savings on their Washington, D.C. Dulles Intl Airport to Seattle flight should consider departing on Friday evenings when fares are most often at their lowest. Monday evenings flights should be avoided if possible as fares are typically the most expensive at this time.
Food
Comfort
Entertainment
Crew
Overall
Boarding
Reviews
Anonymous,Jun 2026
RDU - SEA
Food
Comfort
Entertainment
Crew
Overall
Boarding
Reviews
Anonymous,Jun 2026
RDU - SEA
Food
Comfort
Entertainment
Crew
Overall
Boarding
Reviews
Anonymous,Jun 2026
RDU - SEA
Food
Comfort
Entertainment
Crew
Overall
Boarding
Reviews
Anonymous,Jun 2026
RDU - SEA
Food
Comfort
Entertainment
Crew
Overall
Boarding
Reviews
Anonymous,Jun 2026
RDU - SEA
Food
Comfort
Entertainment
Crew
Overall
Boarding
Reviews
Anonymous,Jun 2026
RDU - SEA
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$121 | Average$307 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$138 | Average$317 | FlexibilityNo cancel fee | On-time85% | |
| Cheapest$144 | Average$358 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$199 | Average$437 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$221 | Average$434 | FlexibilityNo cancel fee | On-time75% | |
| Cheapest$337 | Average$527 | FlexibilityNo cancel fee | On-time71% |