CA $161 Cheap Flights from Seattle (SEA) to Washington (IAD)

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

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

Prices were available within the past 7 days and start at CA $161 for one-way flights and CA $268 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

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

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Alternative airports near Washington

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

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

January is typically the cheapest month to fly

From CA $233 - CA $496 per traveller.

Frequently asked questions

How much is a flight from Sea-Tac Airport to IAD?
Start packing your suitcase, because round-trip flights from Sea-Tac Airport to Washington Dulles Intl. Airport (IAD) start from CA $268. That's based on fares advertised within the last 7 days on Expedia for flights departing within the next year. Prices can go up quickly, so book now to nab 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 Sea-Tac Airport to Dulles Intl. Airport?
When it comes to cancellation fees, each airline has its own terms and conditions. If you decide to cancel your vacation, head to our Customer Service Portal.
How do I find cheap flights from Sea-Tac Airport to IAD that have flexible change policies?
Plenty of carriers will allow you to move your flight without a change fee. All you pay is the difference in the ticket price. When looking for Sea-Tac Airport to Washington Dulles Intl. Airport (IAD) flights, you'll find a "No change fees" box for you to select.
How many hours is the flight from SEA to Washington Dulles Intl. Airport (IAD)?
The average flight between SEA and Dulles Intl. Airport is 13 hours and 20 minutes. If you're travelling with kids, it's always a good idea to pack some snacks or fruit in your carry-on luggage.
How far is the flight from Sea-Tac Airport to IAD?
It's around 3,700 kilometres from SeaTac to Chantilly, so expect to be up in the air for a while. Keep yourself occupied by packing things like a magazine or a thrilling novel.
Which airlines fly direct from Sea-Tac Airport to IAD?
Many adventurers choose to fly with Alaska Airlines (AS) from Sea-Tac Airport to Washington Dulles Intl. Airport (IAD). It offers 30 flights every month, so you can pick a flight time that's perfect for you. You could also check out the fares available with United Airlines (UA). This carrier operates 30 monthly flights between SeaTac and Chantilly.
Are Sea-Tac Airport to Dulles Intl. Airport flight tickets cheaper when they're purchased at the last minute?
Last-minute bookings from Sea-Tac Airport to Dulles Intl. Airport can be hit-or-miss. It is possible to score a bargain, but you could also miss out completely! If you'd prefer to start planning ahead of time, Expedia compares flight deals up to 12 months in advance. Just bear in mind that not all airlines issue their prices that far in advance. Our top tip? Check back often as prices are updated frequently.

Travel information

Origin airport
Seattle - Tacoma Intl.
Destination airport
Washington Dulles Intl.
Airlines serving
Alaska Airlines, American Airlines, Delta, United
Roundtrip price
CA $268
Distance
3679 km
Average flight time
8 hours 32 mins

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