CA $177 Cheap Flights from Washington (IAD) to Seattle (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 $177 for one-way flights and CA $355 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

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

Frequently asked questions

How much is a flight from Washington Dulles Intl. Airport (IAD) to Seattle - Tacoma Intl. Airport (SEA)?
Start packing your bags, because round-trip flights from IAD to Sea-Tac Airport start from CA $355. That’s based on fares advertised within the last 7 days on Expedia for flights departing within the next year. Prices can change quickly, so book today to get the best deal. Prices and availability are subject to change. Additional terms apply.
Do I need to pay a cancellation fee if I cancel my flight from IAD to Sea-Tac Airport?
Most flights can be conveniently canceled online, but whether you incur a fee differs between airlines. If you do need to cancel your vacation, follow the instructions in the Customer Service Portal.
How do I find cheap flights from Dulles Intl. Airport to Seattle - Tacoma Intl. Airport (SEA) that have flexible change policies?
Many airlines offer the option to reschedule your flight without a change fee. All you pay is the difference between the original flight and the new flight. When you’re searching for Dulles Intl. Airport to Seattle - Tacoma Intl. Airport (SEA) flights, you’ll see a “no change fees” filter for you to select.
How far is the flight from Dulles Intl. Airport to Seattle - Tacoma Intl. Airport (SEA)?
You’ll be in the air for a while, as the flight distance between Chantilly and SeaTac is 3,700 kilometers. Set up a playlist of your favorite songs before leaving home to keep yourself entertained during your trip.
Which airlines fly direct from Washington Dulles Intl. Airport (IAD) to SEA?
United Airlines (UA) is a popular option. It offers 60 flights from IAD to Sea-Tac Airport each month. Offering 56 flights a month along this route, Alaska Airlines (AS) is another top pick.
Are IAD to Sea-Tac Airport flight tickets cheaper when they're purchased at the last minute?
It is possible to find a fantastic last-minute deal from IAD to Seattle - Tacoma Intl. Airport (SEA), but it can also be hit-or-miss. As many airlines release seats up to 12 months in advance, it’s worthwhile keeping an eye on fares early and being ready to pounce when you see a good bargain. Expedia compares air carrier prices and updates flight deals frequently, so you can rest assured you’re always seeing the latest offers.
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