
Most accurate provider | CheapOair 3 stars |
|---|---|
Most trusted provider | CheapOair 3 stars |
Round-trip from | $237 (Cheapflightsfares) |
One-way from | $141 (United Airlines) |
Popular in | December |
Cheapest in | September |
Average price | $376 |
Good round-trip deal | $361 or less |
Good one-way deal | $216 or less |
Fly from
Fly to
Route
Depart
Return
Price
Washington, D.C.Seattle
IAD - SEA
IADSEA
Washington, D.C. Dulles Intl
Wed 12/3
7:15 am-10:12 am
Nonstop5h 57m
Seattle/Tacoma Intl
Sat 12/13
3:30 pm-11:27 pm
Nonstop4h 57m
Washington, D.C.Seattle
IAD - SEA
IADSEA
Washington, D.C. Dulles Intl
Tue 12/9
5:37 pm-12:12 am
1 stop9h 35m
Seattle/Tacoma Intl
Sat 12/13
8:40 am-4:36 pm
Nonstop4h 56m
Washington, D.C.Seattle
IAD - SEA
IADSEA
Washington, D.C. Dulles Intl
Fri 12/5
5:37 pm-12:12 am
1 stop9h 35m
Seattle/Tacoma Intl
Sun 12/14
10:11 pm-6:06 am
Nonstop4h 55m
Washington, D.C.Seattle
IAD - SEA
IADSEA
Washington, D.C. Dulles Intl
Thu 12/4
5:37 pm-12:12 am
1 stop9h 35m
Seattle/Tacoma Intl
Mon 12/8
10:11 pm-6:06 am
Nonstop4h 55m
Washington, D.C.Seattle
IAD - SEA
IADSEA
Washington, D.C. Dulles Intl
Thu 12/4
5:37 pm-12:12 am
1 stop9h 35m
Seattle/Tacoma Intl
Wed 12/10
8:40 am-4:36 pm
Nonstop4h 56m
Washington, D.C.Seattle
IAD - SEA
IADSEA
Washington, D.C. Dulles Intl
Tue 12/9
5:37 pm-12:12 am
1 stop9h 35m
Seattle/Tacoma Intl
Sun 12/14
10:11 pm-6:06 am
Nonstop4h 55m
Washington, D.C.Seattle
IAD - SEA
IADSEA
Washington, D.C. Dulles Intl
Thu 1/8
12:23 pm-8:00 pm
1 stop10h 37m
Seattle/Tacoma Intl
Sun 1/11
3:20 pm-11:10 pm
Nonstop4h 50m
Washington, D.C.Seattle
IAD - SEA
IADSEA
Washington, D.C. Dulles Intl
Wed 12/3
5:37 pm-12:52 pm
1 stop22h 15m
Seattle/Tacoma Intl
Thu 12/11
10:11 pm-6:06 am
Nonstop4h 55m
Washington, D.C.Spokane
IAD - GEG
IADGEG
Washington, D.C. Dulles Intl
Mon 12/8
7:15 am-12:29 pm
1 stop8h 14m
Spokane
Mon 12/15
1:10 pm-11:27 pm
1 stop7h 17m
Washington, D.C.Spokane
IAD - GEG
IADGEG
Washington, D.C. Dulles Intl
Thu 12/11
7:15 am-2:55 pm
1 stop10h 40m
Spokane
Mon 12/15
1:10 pm-11:27 pm
1 stop7h 17m
Currently, April is the cheapest month in which you can book a flight from Washington, D.C. Dulles Intl Airport to State of Washington (average of $158). Flying from Washington, D.C. Dulles Intl Airport to State of Washington in March is currently the most expensive (average of $243). 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.
Unlike at noon, when flights are generally more expensive, you can save up to 7% on flights from Washington, D.C. Dulles Intl Airport to State of Washington by exploring options for tickets in the evening.
Travelers seeking maximum savings on their Washington, D.C. Dulles Intl Airport to State of Washington flight should consider departing on Tuesday afternoons 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.
The most flights from IAD to USWA are scheduled on a Wednesday (23 on average). You will have fewer flight options on Friday, which is when the least amount of flights are scheduled (14 on average).
Comfort
Overall
Crew
Boarding
Food
Entertainment
Reviews
Anonymous,Aug 2025
MFR - SEA
Comfort
Overall
Crew
Boarding
Food
Entertainment
Reviews
Anonymous,Aug 2025
MFR - SEA
Comfort
Overall
Crew
Boarding
Food
Entertainment
Reviews
Anonymous,Aug 2025
MFR - SEA
Comfort
Overall
Crew
Boarding
Food
Entertainment
Reviews
Anonymous,Aug 2025
MFR - SEA
Comfort
Overall
Crew
Boarding
Food
Entertainment
Reviews
Anonymous,Aug 2025
MFR - SEA
Comfort
Overall
Crew
Boarding
Food
Entertainment
Reviews
Anonymous,Aug 2025
MFR - SEA
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$111 | Average$260 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$149 | Average$393 | FlexibilityNo cancel fee | On-time85% | |
| Cheapest$184 | Average$393 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$260 | Average$500 | FlexibilityNo cancel fee | On-time75% | |
| Cheapest$278 | Average$451 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$321 | Average$527 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$367 | Average$498 | FlexibilityNo cancel fee | On-time63% |