Saver Fare allows a carry-on bag, unlike many basic economy options.
Alaska Lounge offers fresh seasonal food and craft cocktails, surpassing many competitors.

Most accurate provider | eDreams 3 stars |
|---|---|
Most trusted provider | eDreams 3 stars |
Round-trip from | $233 (United Airlines) |
One-way from | $139 (United Airlines) |
Popular in | December |
Cheapest in | October |
Average price | $483 |
Good round-trip deal | $337 or less |
Good one-way deal | $193 or less |
Fly from
Fly to
Route
Depart
Return
Price
SeattleWashington, D.C.
SEA - IAD
SEAIAD
Seattle/Tacoma Intl
Fri 1/16
7:00 am-5:35 pm
1 stop7h 35m
Washington, D.C. Dulles Intl
Mon 1/19
5:17 pm-10:43 pm
1 stop8h 26m
SeattleWashington, D.C.
SEA - IAD
SEAIAD
Seattle/Tacoma Intl
Tue 12/9
8:40 am-4:36 pm
Nonstop4h 56m
Washington, D.C. Dulles Intl
Tue 12/16
7:34 am-10:35 am
Nonstop6h 01m
SeattleWashington, D.C.
SEA - IAD
SEAIAD
Seattle/Tacoma Intl
Wed 12/10
10:40 am-9:18 pm
1 stop7h 38m
Washington, D.C. Dulles Intl
Fri 12/12
6:30 am-11:45 am
1 stop8h 15m
SeattleWashington, D.C.
SEA - IAD
SEAIAD
Seattle/Tacoma Intl
Thu 1/1
10:55 pm-9:46 am
1 stop7h 51m
Washington, D.C. Dulles Intl
Thu 1/8
6:00 am-10:42 am
1 stop7h 42m
SeattleWashington, D.C.
SEA - IAD
SEAIAD
Seattle/Tacoma Intl
Thu 1/8
9:55 am-9:55 pm
1 stop9h 00m
Washington, D.C. Dulles Intl
Sun 1/11
5:30 am-1:30 pm
2 stops11h 00m
SeattleWashington, D.C.
SEA - IAD
SEAIAD
Seattle/Tacoma Intl
Thu 12/25
10:00 am-6:09 pm
Nonstop5h 09m
Washington, D.C. Dulles Intl
Thu 1/1
7:33 am-10:20 am
Nonstop5h 47m
SeattleWashington, D.C.
SEA - IAD
SEAIAD
Seattle/Tacoma Intl
Thu 1/15
5:10 pm-7:35 am
1 stop11h 25m
Washington, D.C. Dulles Intl
Sun 1/18
5:17 pm-10:43 pm
1 stop8h 26m
SeattleWashington, D.C.
SEA - IAD
SEAIAD
Seattle/Tacoma Intl
Fri 1/2
11:15 pm-7:11 am
Nonstop4h 56m
Washington, D.C. Dulles Intl
Mon 1/5
9:47 am-6:06 pm
1 stop11h 19m
SeattleWashington, D.C.
SEA - IAD
SEAIAD
Seattle/Tacoma Intl
Wed 1/14
8:40 am-11:18 pm
2 stops11h 38m
Washington, D.C. Dulles Intl
Sun 1/18
5:17 pm-10:43 pm
1 stop8h 26m
SeattleWashington, D.C.
SEA - IAD
SEAIAD
Seattle/Tacoma Intl
Mon 12/8
10:40 am-11:21 pm
2 stops9h 41m
Washington, D.C. Dulles Intl
Fri 12/12
4:10 pm-12:50 am
1 stop11h 40m
| Provider | Price Accuracy | Trust Score* |
|---|---|---|
| Price Accuracy2 stars | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*1 star | |
| Price Accuracy3 stars | Trust Score*3 stars | |
| Price Accuracy1 star | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*3 stars | |
| Price Accuracy2 stars | Trust Score*3 stars | |
| Price Accuracy- | Trust Score*1 star |
Booking 77 days in advance of your planned departure date is, on average, the best time to get cheap flights from Seattle to Washington, D.C. Dulles Intl Airport. The general trend is that the closer you book to the departure date, the more expensive your flight will be.
Currently, March is the cheapest month in which you can book a flight from Seattle to Washington, D.C. Dulles Intl Airport (average of $143). Flying from Seattle to Washington, D.C. Dulles Intl Airport in June is currently the most expensive (average of $295). 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.
A simple way to save on the total cost of your ticket is to fly from Seattle to Washington, D.C. Dulles Intl Airport in the afternoon. If you’re flexible enough to do this you can expect to save up to 34% on your trip compared to booking a flight in the morning.
Travelers seeking maximum savings on their Seattle to Washington, D.C. Dulles Intl Airport flight should consider departing on Saturday afternoons when fares are most often at their lowest. Sunday at noon flights should be avoided if possible as fares are typically the most expensive at this time.
Comfort
Entertainment
Overall
Boarding
Food
Crew
Reviews
Anonymous,Sep 2025
SEA - MKE
Comfort
Entertainment
Overall
Boarding
Food
Crew
Reviews
Anonymous,Sep 2025
SEA - MKE
Comfort
Entertainment
Overall
Boarding
Food
Crew
Reviews
Anonymous,Sep 2025
SEA - MKE
Comfort
Entertainment
Overall
Boarding
Food
Crew
Reviews
Anonymous,Sep 2025
SEA - MKE
Comfort
Entertainment
Overall
Boarding
Food
Crew
Reviews
Anonymous,Sep 2025
SEA - MKE
Comfort
Entertainment
Overall
Boarding
Food
Crew
Reviews
Anonymous,Sep 2025
SEA - MKE
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$143 | Average$332 | FlexibilityNo cancel fee | On-time85% | |
| Cheapest$188 | Average$298 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$192 | Average$380 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$275 | Average$431 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$280 | Average$426 | FlexibilityNo cancel fee | On-time75% | |
| Cheapest$336 | Average$708 | FlexibilityNo cancel fee | On-time71% |