₩217,600 Cheap Flights from Washington (IAD) to Seattle (SEA)

View ₩217,600 flight on Tue, Oct 14, 2025Opens in a new window

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

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Cheap Flights from Washington to Seattle (IAD-SEA)

Prices were available within the past 7 days and start at ₩217,600 for one-way flights and ₩380,100 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Delta
Sat, Aug 23 - Sat, Aug 30
IAD
Washington
SEA
Seattle
₩380,100 Roundtrip, found 5 days ago
₩380,100
Roundtrip
found 5 days ago
Select Delta flight, departing Sat, Aug 23 from Washington to Seattle, returning Sat, Aug 30, priced at ₩380,100 found 5 days ago
Delta
Wed, Nov 12 - Sat, Nov 15
IAD
Washington
SEA
Seattle
₩384,200 Roundtrip, found 6 days ago
₩384,200
Roundtrip
found 6 days ago
Select Delta flight, departing Wed, Nov 12 from Washington to Seattle, returning Sat, Nov 15, priced at ₩384,200 found 6 days ago
Delta
Mon, Aug 25 - Tue, Sep 2
IAD
Washington
SEA
Seattle
₩411,800 Roundtrip, found 6 days ago
₩411,800
Roundtrip
found 6 days ago
Select Delta flight, departing Mon, Aug 25 from Washington to Seattle, returning Tue, Sep 2, priced at ₩411,800 found 6 days ago
Delta
Mon, Sep 15 - Sun, Sep 28
IAD
Washington
SEA
Seattle
₩412,100 Roundtrip, found 11 hours ago
₩412,100
Roundtrip
found 11 hours ago
Select Delta flight, departing Mon, Sep 15 from Washington to Seattle, returning Sun, Sep 28, priced at ₩412,100 found 11 hours ago
Delta
Fri, Oct 17 - Thu, Oct 23
IAD
Washington
SEA
Seattle
₩448,700 Roundtrip, found 4 days ago
₩448,700
Roundtrip
found 4 days ago
Select Delta flight, departing Fri, Oct 17 from Washington to Seattle, returning Thu, Oct 23, priced at ₩448,700 found 4 days ago
Delta
Wed, Oct 1 - Wed, Oct 8
IAD
Washington
SEA
Seattle
₩463,800 Roundtrip, found 4 days ago
₩463,800
Roundtrip
found 4 days ago
Select Delta flight, departing Wed, Oct 1 from Washington to Seattle, returning Wed, Oct 8, priced at ₩463,800 found 4 days ago
Delta
Wed, Oct 1 - Wed, Oct 8
IAD
Washington
SEA
Seattle
₩503,400 Roundtrip, found 4 days ago
₩503,400
Roundtrip
found 4 days ago
Select Delta flight, departing Wed, Oct 1 from Washington to Seattle, returning Wed, Oct 8, priced at ₩503,400 found 4 days ago
Delta
Wed, Oct 1 - Wed, Oct 8
IAD
Washington
SEA
Seattle
₩503,600 Roundtrip, found 4 days ago
₩503,600
Roundtrip
found 4 days ago
Select Delta flight, departing Wed, Oct 1 from Washington to Seattle, returning Wed, Oct 8, priced at ₩503,600 found 4 days ago
United
Wed, Nov 12 - Sat, Nov 15
IAD
Washington
SEA
Seattle
₩522,600 Roundtrip, found 6 days ago
₩522,600
Roundtrip
found 6 days ago
Select United flight, departing Wed, Nov 12 from Washington to Seattle, returning Sat, Nov 15, priced at ₩522,600 found 6 days ago
American Airlines
Mon, Aug 25 - Tue, Sep 2
IAD
Washington
SEA
Seattle
₩530,800 Roundtrip, found 4 days ago
₩530,800
Roundtrip
found 4 days ago
Select American Airlines flight, departing Mon, Aug 25 from Washington to Seattle, returning Tue, Sep 2, priced at ₩530,800 found 4 days ago

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

September is typically the cheapest month to fly

From ₩254,153 - ₩410,963 per traveler.

Graph displaying average flight prices per month

Flights from Washington (IAD) to Seattle (SEA)
Origin airport
Washington Dulles Intl.
Destination airport
Seattle - Tacoma Intl.
Airlines serving
American Airlines, Delta, United
Roundtrip price
₩380,100
Distance
3679 km
Average flight time
2 hours 48 mins

Chantilly to Seattle Flights

Sometimes you just need to get out of town or maybe you’re looking for a change of scenery. Regardless of the reason, a flight from Chantilly to Seattle will do just the trick! Go on, plan to see all the famous landmarks and eat your weight in the local cuisine. Your trip is beckoning, so answer the call by packing your suitcase and filling your travel itinerary with exploring Seattle.

Whether you’re flying for business or jet-setting on your personal time, you’ve come to the right place. Here at Expedia.com, we’ll pair you up with IAD to SEA flights that won’t make your bank account wince. Ready to temporarily leave behind Chantilly for new horizons? Browse through our cheap airfare, and filter by flight times and dates until you find just what you had in mind. From flights without layovers to ones that arrive early in the morning, you’ll come across plane tickets that suit your travel preferences. You can even bundle your flight to SEA with hotels and car rentals to score even bigger savings.

All set to hit the clouds? Book your travel arrangements with us today and have left-over money to put toward your travel outings and adventures.

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 ₩380,100. 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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