Cheap Flights from Seattle (SEA) to Washington (IAD) from HK$1,250~

View HK$1,250 flight on Tue, 26 Aug 2025Opens in a new window

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

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Find Cheap Flights from Seattle (SEA) to Washington (IAD)

Prices were available within the past 7 days and start at HK$1,250 for one-way flights and HK$3,608 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

United
Thu, 14 Aug - Wed, 27 Aug
SEA
Seattle
IAD
Washington
HK$3,608 Return, found 1 day ago
HK$3,608
Return
found 1 day ago
Select United flight, departing Thu, 14 Aug from Seattle to Washington, returning Wed, 27 Aug, priced at HK$3,608 found 1 day ago
United
Thu, 14 Aug - Wed, 27 Aug
SEA
Seattle
IAD
Washington
HK$3,685 Return, found 1 day ago
HK$3,685
Return
found 1 day ago
Select United flight, departing Thu, 14 Aug from Seattle to Washington, returning Wed, 27 Aug, priced at HK$3,685 found 1 day ago
United
Thu, 14 Aug - Sat, 30 Aug
SEA
Seattle
IAD
Washington
HK$3,833 Return, found 1 day ago
HK$3,833
Return
found 1 day ago
Select United flight, departing Thu, 14 Aug from Seattle to Washington, returning Sat, 30 Aug, priced at HK$3,833 found 1 day ago
Delta
Sat, 16 Aug - Wed, 27 Aug
SEA
Seattle
IAD
Washington
HK$3,983 Return, found 1 day ago
HK$3,983
Return
found 1 day ago
Select Delta flight, departing Sat, 16 Aug from Seattle to Washington, returning Wed, 27 Aug, priced at HK$3,983 found 1 day ago
American Airlines
Thu, 14 Aug - Wed, 27 Aug
SEA
Seattle
IAD
Washington
HK$3,995 Return, found 1 day ago
HK$3,995
Return
found 1 day ago
Select American Airlines flight, departing Thu, 14 Aug from Seattle to Washington, returning Wed, 27 Aug, priced at HK$3,995 found 1 day ago
United
Thu, 14 Aug - Wed, 27 Aug
SEA
Seattle
IAD
Washington
HK$4,038 Return, found 1 day ago
HK$4,038
Return
found 1 day ago
Select United flight, departing Thu, 14 Aug from Seattle to Washington, returning Wed, 27 Aug, priced at HK$4,038 found 1 day ago
American Airlines
Thu, 14 Aug - Wed, 27 Aug
SEA
Seattle
IAD
Washington
HK$4,071 Return, found 1 day ago
HK$4,071
Return
found 1 day ago
Select American Airlines flight, departing Thu, 14 Aug from Seattle to Washington, returning Wed, 27 Aug, priced at HK$4,071 found 1 day ago
United
Thu, 14 Aug - Wed, 27 Aug
SEA
Seattle
IAD
Washington
HK$4,115 Return, found 1 day ago
HK$4,115
Return
found 1 day ago
Select United flight, departing Thu, 14 Aug from Seattle to Washington, returning Wed, 27 Aug, priced at HK$4,115 found 1 day ago
Delta
Sat, 16 Aug - Sun, 24 Aug
SEA
Seattle
IAD
Washington
HK$4,145 Return, found 1 day ago
HK$4,145
Return
found 1 day ago
Select Delta flight, departing Sat, 16 Aug from Seattle to Washington, returning Sun, 24 Aug, priced at HK$4,145 found 1 day ago
Hawaiian Airlines
Thu, 14 Aug - Fri, 29 Aug
SEA
Seattle
IAD
Washington
HK$4,383 Return, found 1 day ago
HK$4,383
Return
found 1 day ago
Select Hawaiian Airlines flight, departing Thu, 14 Aug from Seattle to Washington, returning Fri, 29 Aug, priced at HK$4,383 found 1 day ago

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

September is typically the cheapest month to fly

From HK$1,438 - HK$2,331 per traveller.

Graph displaying average flight prices per month

Seattle to Washington route information
Origin airport
Seattle - Tacoma Intl.
Destination airport
Washington Dulles Intl.
Airlines serving
American Airlines, Delta, Hawaiian Airlines, United
Return price
HK$3,608
Distance
3679 km
Average flight time
8 hours 12 mins

Flights from Seattle to Chantilly

Book cheap flights from Seattle (SEA) to Chantilly (IAD) on Expedia.com.hk. Find the best flight deals to destinations around the world for your next leisure or business travel on Expedia.com.hk.

Search for flights from Seattle (SEA) to Chantilly (IAD) to find great flight deals suitable to your travel date and time. Expedia.com.hk flight booking search engine is simple to use and looking for cheap flights is as easy as a click of a mouse or on your mobile devices.

Be assured that you’re seeing the best price guaranteed! Our friendly customer service representatives are here to serve you 24 hours day to provide assistance and answer any questions that you may have about booking your Seattle (SEA) to Chantilly (IAD) trip. Call us at 3077-4857 (direct number - 24 hours day for English).

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If you would like to book flights to Chantilly more flexibly, many prefer to purchase one-way tickets with options to take different airlines. A one way ticket to Chantilly is HK$1,250 now!

 

Frequently asked questions

How much is a flight from Sea-Tac Airport to Washington Dulles Intl. Airport (IAD)?
The lowest price advertised for a round-trip journey between SEA and Washington Dulles Intl. Airport (IAD) is HK$3,608. But you better act quick. This price is based on fares quoted within the last 7 days on Expedia for flights departing within the next year. 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 Washington Dulles Intl. Airport (IAD)?
Most flights can be canceled online, but whether or not you incur a fee varies between airlines. If you do need to cancel your getaway, follow the instructions in the Customer Service Portal.
How do I find cheap flights from 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 SEA to IAD flights, you'll see a "no change fees" filter for you to select.
How far is the flight from Sea-Tac Airport to Dulles Intl. Airport?
The flight distance between Sea-Tac Airport (SEA) and Washington Dulles Intl. Airport (IAD) (IAD) is 3,700 kilometers. Sneak in a nap or make a start on the latest bestseller and the trip will zip on by.
Which airlines fly direct from Seattle - Tacoma Intl. Airport (SEA) to Dulles Intl. Airport?
There are a few airlines that fly directly from Seattle - Tacoma Intl. Airport (SEA) to IAD. United Airlines (UA) is a great choice, offering 60 flights every month. Offering 56 flights every month along this route, Alaska Airlines (AS) is another good option.
Are SEA to Washington Dulles Intl. Airport (IAD) flight tickets cheaper when they're purchased at the last minute?
Booking last minute from Seattle - Tacoma Intl. Airport (SEA) to IAD can be hit-or-miss. You might be lucky and score a bargain, but you could also miss out completely! If you'd rather play it safe and start your travel planning early on, Expedia compares flight deals up to a year in advance. Just remember that not all airlines advertise their prices that far in advance. Our top tip? Check back often as prices are updated regularly.

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