CA $170 Cheap Flights from Washington (IAD) to Seattle (SEA)

Popular airlines from Washington Dulles International Airport (IAD) to Seattle-Tacoma International Airport (SEA)

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Cheap flights from Washington (IAD) to Seattle (SEA)

Prices were available within the past 7 days and start at CA $170 for one-way flights and CA $353 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Alaska Airlines
American Airlines
American Airlines
Alaska Airlines
American Airlines
Alaska Airlines
Alaska Airlines
Delta
United
Sun Country Airlines

Alternative airports near Seattle

Prices were available within the past 7 days. Prices and availability are subject to change.

Frequently asked questions

How much is a flight from IAD to SEA?
Within the past 7 days on Expedia, for flights departing within the next year, the lowest price advertised for a round-trip flight between Dulles Intl. Airport and Sea-Tac Airport was CA $353. Fares this good don't stick around for long, so make sure you book yours today. Prices and availability are subject to change. Additional terms apply.
Do I need to pay a cancellation fee if I cancel my flight from Washington Dulles Intl. Airport (IAD) to Sea-Tac Airport?
The majority of flights can be conveniently cancelled online, but whether you are charged a fee depends on your airline. If you do have to cancel your trip, follow the instructions in the Customer Service Portal.
How do I find cheap flights from Dulles Intl. Airport to Sea-Tac Airport that have flexible change policies?
Plenty of airlines will allow you to reschedule your flight at no extra charge. All you pay is the difference in the ticket price. When searching for IAD to Sea-Tac Airport flights, you'll find a "No change fees" box for you to select.
How many hours is the flight from Dulles Intl. Airport to Sea-Tac Airport?
There are plenty of ways to make the 13 hours and 12 minutes between Dulles Intl. Airport and Seattle - Tacoma Intl. Airport (SEA) fly by. If you want to be productive, organize your camera roll or delete all those backed-up emails. A good snooze also helps pass the time!
How far is the flight from IAD to Seattle - Tacoma Intl. Airport (SEA)?
The flying distance between Washington Dulles Intl. Airport (IAD) (IAD) and Sea-Tac Airport (SEA) is 3,700 kilometres. Work your way through your travel song playlist or bury your nose in a book and the trip will zip on by.
Which airlines fly direct from IAD to Seattle - Tacoma Intl. Airport (SEA)?
There are several airlines that fly straight from Washington Dulles Intl. Airport (IAD) to Sea-Tac Airport. Alaska Airlines (AS) is a popular choice, offering 30 flights each month. Operating 30 flights every month on this route, Delta (DL) is another traveller favourite.
Are IAD to Sea-Tac Airport flight tickets cheaper when they're purchased at the last minute?
Fares from Washington Dulles Intl. Airport (IAD) to Sea-Tac Airport are available up to a year before departure on Expedia. And although you may occasionally score great last-minute deal, it's never a sure thing. Also, booking your flights ahead of time means you'll have more choices — and you can avoid getting stuck in the dreaded middle seat! We're constantly updating our fares to make sure you get the biggest bargains, so check back often for all the latest specials.

Travel information

Origin airport
Washington Dulles Intl.
Destination airport
Seattle - Tacoma Intl.
Airlines serving
Alaska Airlines, American Airlines, Delta, United
Roundtrip price
CA $352
Distance
3679 km
Average flight time
2 hours 56 mins

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