￥18,640 Cheap Flights from Seattle (SEA) to Washington (IAD)

View ￥18,640 flight on Tue, Jan 20, 2026Opens in a new window

Popular airlines from Seattle to Washington, DC (IAD-Washington Dulles Intl.)

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Cheap Flights from Seattle to Washington (SEA-IAD)

Prices were available within the past 7 days and start at ￥18,640 for one-way flights and ￥31,030 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Delta
Fri, Mar 6 - Mon, Mar 9
SEA
Seattle
IAD
Washington
￥31,030 Roundtrip, found 2 days ago
￥31,030
Roundtrip
found 2 days ago
Select Delta flight, departing Fri, Mar 6 from Seattle to Washington, returning Mon, Mar 9, priced at ￥31,030 found 2 days ago
Delta
Fri, Mar 6 - Mon, Mar 9
SEA
Seattle
IAD
Washington
￥32,550 Roundtrip, found 2 days ago
￥32,550
Roundtrip
found 2 days ago
Select Delta flight, departing Fri, Mar 6 from Seattle to Washington, returning Mon, Mar 9, priced at ￥32,550 found 2 days ago
American Airlines
Sun, Jan 25 - Sun, Feb 1
SEA
Seattle
IAD
Washington
￥34,220 Roundtrip, found 6 days ago
￥34,220
Roundtrip
found 6 days ago
Select American Airlines flight, departing Sun, Jan 25 from Seattle to Washington, returning Sun, Feb 1, priced at ￥34,220 found 6 days ago
Hawaiian Airlines
Mon, Jan 5 - Thu, Jan 22
SEA
Seattle
IAD
Washington
￥37,050 Roundtrip, found 4 days ago
￥37,050
Roundtrip
found 4 days ago
Select Hawaiian Airlines flight, departing Mon, Jan 5 from Seattle to Washington, returning Thu, Jan 22, priced at ￥37,050 found 4 days ago
Delta
Fri, Mar 6 - Mon, Mar 9
SEA
Seattle
IAD
Washington
￥37,280 Roundtrip, found 2 days ago
￥37,280
Roundtrip
found 2 days ago
Select Delta flight, departing Fri, Mar 6 from Seattle to Washington, returning Mon, Mar 9, priced at ￥37,280 found 2 days ago
Delta
Mon, Feb 2 - Fri, Feb 6
SEA
Seattle
IAD
Washington
￥37,400 Roundtrip, found 1 day ago
￥37,400
Roundtrip
found 1 day ago
Select Delta flight, departing Mon, Feb 2 from Seattle to Washington, returning Fri, Feb 6, priced at ￥37,400 found 1 day ago
Delta
Fri, Mar 6 - Mon, Mar 9
SEA
Seattle
IAD
Washington
￥38,800 Roundtrip, found 2 days ago
￥38,800
Roundtrip
found 2 days ago
Select Delta flight, departing Fri, Mar 6 from Seattle to Washington, returning Mon, Mar 9, priced at ￥38,800 found 2 days ago
Delta
Sun, Jan 25 - Sun, Feb 1
SEA
Seattle
IAD
Washington
￥38,900 Roundtrip, found 6 days ago
￥38,900
Roundtrip
found 6 days ago
Select Delta flight, departing Sun, Jan 25 from Seattle to Washington, returning Sun, Feb 1, priced at ￥38,900 found 6 days ago
Alaska Airlines
Fri, Mar 6 - Mon, Mar 9
SEA
Seattle
IAD
Washington
￥43,290 Roundtrip, found 2 days ago
￥43,290
Roundtrip
found 2 days ago
Select Alaska Airlines flight, departing Fri, Mar 6 from Seattle to Washington, returning Mon, Mar 9, priced at ￥43,290 found 2 days ago
United
Sun, Jan 25 - Sun, Feb 1
SEA
Seattle
IAD
Washington
￥46,860 Roundtrip, found 6 days ago
￥46,860
Roundtrip
found 6 days ago
Select United flight, departing Sun, Jan 25 from Seattle to Washington, returning Sun, Feb 1, priced at ￥46,860 found 6 days ago

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

February is typically the cheapest month to fly

From ￥24,729 - ￥46,058 per traveler.
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Flights from Seattle (SEA) to Washington (IAD)
Origin airport
Seattle - Tacoma Intl.
Destination airport
Washington Dulles Intl.
Airlines serving
Alaska Airlines, American Airlines, Delta, United
Roundtrip price
￥31,030
Distance
3679 km

Seattle to Washington 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 Seattle to 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 Washington.

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 SEA to IAD flights that won’t make your bank account wince. Ready to temporarily leave behind Seattle 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 IAD 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 Seattle - Tacoma Intl. Airport (SEA) to Washington Dulles Intl. Airport (IAD)?
Within the past 7 days on Expedia, for flights departing within the next year, the lowest price listed for a round-trip journey from Sea-Tac Airport to Dulles Intl. Airport was ￥31,030. Fares this good don't hang around, so 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 Sea-Tac Airport to Dulles Intl. Airport?
Every airline has different terms and conditions. If you decide to cancel your escape, visit our Customer Service Portal.
How do I find cheap flights from Seattle - Tacoma Intl. Airport (SEA) to IAD 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 Seattle - Tacoma Intl. Airport (SEA) to IAD flights, you'll see a "no change fees" filter for you to select.
How many hours is the flight from SEA to Dulles Intl. Airport?
It takes about 4 hours and 59 minutes to journey from SEA to Washington Dulles Intl. Airport (IAD). But with your favorite playlist and a good novel, the hours will pass by quicker.
How far is the flight from SEA to Dulles Intl. Airport?
The flight distance between Sea-Tac Airport and Dulles Intl. Airport is 3,700 kilometers. Pack yourself a drink, some snacks and a good book to read. Keep yourself busy in the air and the hours will zip by.
Which airlines fly direct from Sea-Tac Airport to Washington Dulles Intl. Airport (IAD)?
Many people like to fly with United Airlines (UA) from SEA to IAD. This leading airline offers 108 flights a month, so you can easily find a flight time that's right for you. If you'd like more options, check out the ticket prices from Alaska Airlines (AS). This carrier offers 82 flights monthly between these airports.
Are SEA to IAD flight tickets cheaper when they're purchased at the last minute?
Booking your trip from Sea-Tac Airport to Dulles Intl. Airport last minute could be your ticket to an awesome deal. However, it could end up costing a good deal more! If you'd rather avoid the risk, book well ahead of your departure date. In fact, Expedia has some of the best bargains up to 12 months in advance. If your preferred air carrier hasn't released tickets yet, check back frequently as deals are updated all the time on Expedia.

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