Cheap Flights From Seattle - Tacoma Intl. (SEA) To Washington Dulles Intl. (IAD)

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Cheapest Flights from Seattle (SEA) to Washington (IAD)

The cheapest flights to Washington Dulles Intl. found within the past 7 days were CA $353 round trip and CA $204 one way. Prices and availability subject to change. Additional terms may apply.

Wed, Sep. 3 - Sat, Sep. 6
SEA
Seattle
IAD
Washington
CA $353 Roundtrip, found 9 hours ago
CA $353
Roundtrip
found 9 hours ago
Select Alaska Airlines flight, departing Wed, Sep. 3 from Seattle to Washington, returning Sat, Sep. 6, priced at CA $353 found 9 hours ago
Tue, Aug. 26 - Sat, Aug. 30
SEA
Seattle
IAD
Washington
CA $359 Roundtrip, found 2 hours ago
CA $359
Roundtrip
found 2 hours ago
Select Alaska Airlines flight, departing Tue, Aug. 26 from Seattle to Washington, returning Sat, Aug. 30, priced at CA $359 found 2 hours ago
Wed, Oct. 8 - Tue, Oct. 14
SEA
Seattle
IAD
Washington
CA $376 Roundtrip, found 6 days ago
CA $376
Roundtrip
found 6 days ago
Select Alaska Airlines flight, departing Wed, Oct. 8 from Seattle to Washington, returning Tue, Oct. 14, priced at CA $376 found 6 days ago
Tue, Oct. 7 - Tue, Oct. 14
SEA
Seattle
IAD
Washington
CA $377 Roundtrip, found 3 days ago
CA $377
Roundtrip
found 3 days ago
Select Hawaiian Airlines flight, departing Tue, Oct. 7 from Seattle to Washington, returning Tue, Oct. 14, priced at CA $377 found 3 days ago
Tue, Sep. 30 - Wed, Oct. 8
SEA
Seattle
IAD
Washington
CA $377 Roundtrip, found 3 days ago
CA $377
Roundtrip
found 3 days ago
Select Delta flight, departing Tue, Sep. 30 from Seattle to Washington, returning Wed, Oct. 8, priced at CA $377 found 3 days ago
Thu, Sep. 11 - Sat, Sep. 13
SEA
Seattle
IAD
Washington
CA $380 Roundtrip, found 17 hours ago
CA $380
Roundtrip
found 17 hours ago
Select Alaska Airlines flight, departing Thu, Sep. 11 from Seattle to Washington, returning Sat, Sep. 13, priced at CA $380 found 17 hours ago
Wed, Sep. 10 - Sun, Sep. 14
SEA
Seattle
IAD
Washington
CA $381 Roundtrip, found 3 hours ago
CA $381
Roundtrip
found 3 hours ago
Select Alaska Airlines flight, departing Wed, Sep. 10 from Seattle to Washington, returning Sun, Sep. 14, priced at CA $381 found 3 hours ago
Sat, Aug. 30 - Sat, Sep. 6
SEA
Seattle
IAD
Washington
CA $383 Roundtrip, found 5 days ago
CA $383
Roundtrip
found 5 days ago
Select Alaska Airlines flight, departing Sat, Aug. 30 from Seattle to Washington, returning Sat, Sep. 6, priced at CA $383 found 5 days ago
Wed, Aug. 27 - Tue, Sep. 2
SEA
Seattle
IAD
Washington
CA $384 Roundtrip, found 3 days ago
CA $384
Roundtrip
found 3 days ago
Select Alaska Airlines flight, departing Wed, Aug. 27 from Seattle to Washington, returning Tue, Sep. 2, priced at CA $384 found 3 days ago
Thu, Sep. 25 - Wed, Oct. 1
SEA
Seattle
IAD
Washington
CA $388 Roundtrip, found 1 hour ago
CA $388
Roundtrip
found 1 hour ago
Select Alaska Airlines flight, departing Thu, Sep. 25 from Seattle to Washington, returning Wed, Oct. 1, priced at CA $388 found 1 hour ago

Frequently asked questions

Are there direct flights from Sea-Tac Airport to Washington Dulles Intl. Airport (IAD)?
Sometimes, it's the journey that counts; other times, it's all about the destination. If you're eager to get to where you're going fast, multiple airlines advertise direct flights from Sea-Tac Airport to Washington Dulles Intl. Airport (IAD), including Alaska Airlines and United Airlines.
What airlines fly from SEA to IAD?
If you're heading to Sterling from Seattle, there are several airlines with direct flights. One of the top carriers is Alaska Airlines (AS), which operates 52 flights each month. You should also check out the deals available through United Airlines (UA). This carrier operates 30 flights monthly on the Seattle to Sterling route. Be sure to compare the two airlines to score the best fare.
What is the best day to buy a plane ticket?
Airfares offered on Friday tend to be the cheapest, according to flight demand on Travelocity.ca in 2021. Purchasing your airfares on a Thursday or Saturday can also provide better value, however our advice if you're looking to save money is to avoid booking on a Wednesday or Sunday. Our data shows that those two days have the highest ticket values on average, so keep this in mind if you're browsing flight deals.
What are the cheapest days to fly?
Frequent travellers may already know this, but earlier in the week is often the cheapest time to fly. Flights departing on a Monday are the cheapest of the week. Since flights towards the middle of the week tend to be more popular, this causes the prices to rise. This is why, on average, airfares booked on Travelocity.ca in 2021 were most expensive for Wednesday departures.
How far in advance can you book a flight?
Here's the deal: It is typically possible to start comparing international airfares on Travelocity.ca up to 12 months in advance. However, it does depend on the carrier as not all airlines release their prices that far out. According to our 2021 flight demand trends, last minute planners can still bag a bargain with some of the cheapest fares appearing 2-4 weeks prior to their travel dates.*According to flight demand on Travelocity.ca from January to December 2021. Savings are subject to change and may vary depending on selections made.

Popular Flight Routes from Seattle (SEA)

Travelers at SEA love to visit these top cities. Roam to the top destinations from Seattle (SEA) today with the cheap prices from Travelocity!

Popular Flight Routes from Washington (IAD)

Travelers at IAD love to visit these top cities. Roam to the top destinations from Washington(IAD) today with the cheap prices from Travelocity!

*Price based on the lowest price found within past 24 hours and based upon one night stay for two adults over the next thirty days. Prices and availability subject to change. Additional terms may apply.