CA $190 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 $190 for one-way flights and CA $377 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Alaska Airlines
Delta
Hawaiian Airlines
Alaska Airlines
Delta
American Airlines
American Airlines
Delta
Delta
United

Find the cheapest month to fly from Washington (IAD) to Seattle (SEA)

September is typically the cheapest month to fly

From CA $251 - CA $406 per traveller.

Graph displaying average flight prices per month

Flight from Washington to Seattle (IAD - SEA) route information
Origin airport
Washington Dulles Intl.
Destination airport
Seattle - Tacoma Intl.
Airlines serving
Alaska Airlines, American Airlines, Delta, Hawaiian Airlines, United
Roundtrip price
CA $377
Distance
3679 km
Average flight time
2 hours 48 mins

Chantilly to Seattle Flights

The easy way to book your flights from Washington to Seattle 

With Expedia, it’s simple to find and book flights to Seattle from Washington whether you’re traveling for business or pleasure. Enter your travel dates, hit search, and choose your flight from 20 airlines that cover this route. There are American Airlines, Qatar Airways, JAL, Austrian, China Eastern Airlines, Delta Air Lines, Copa Airlines, United Airlines, Ethiopian Airlines, Alaska Airlines, Avianca, Iberia, Hawaiian Airlines, Korean Air, Air Tahiti Nui, Brussels Airlines, Lufthansa nonstop flights to Seattle - Tacoma Intl., too.  

Choose your preferred carrier and cabin class with the advanced search tool and select your ideal departure time. Then, if you want, you can see just nonstop or refundable flights. And if you’re traveling last minute, just enter the date to check out flights from Washington to Seattle today, tomorrow, or this week.  

 

Save dollars with cheap flights from Washington Dulles Intl., IAD to Seattle - Tacoma Intl., SEA 

Sort your search results by price to find great deals on your flight from Washington to Seattle—you get all your cheapest options first. Grab yourself a bargain now—the lowest price on flights to Seattle from Washington currently is just CA $377 rising to CA $572.  

Here are more money-saving tips: 

  • Fly in September when flight prices are normally at their lowest 
  • Book about a month to 6 weeks before you travel for the best prices to Seattle  
  • Avoid peak season and weekends when flights can cost more
  • Early morning and late-night flights are sometimes cheaper, so try varying your travel times 
  • One surefire way to save money on your flight is to book your flight and hotel together with Expedia. Sometimes, the savings are so large that the flight is basically free! 

 

Reasons to choose Expedia for your flight to Seattle from Washington 

Whatever your destination, budget, or reason to travel, in just one quick search, you can choose from loads of flights, airlines, and cabin classes. The filters make it quick and easy to find your ideal flights, and if you choose one of the flexible options, you won’t be charged to change your flight. So book your flight to Seattle with Expedia today.

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 $377. 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.

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