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

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

The cheapest flights to Seattle - Tacoma Intl. found within the past 7 days were CA $382 round trip and CA $222 one way. Prices and availability subject to change. Additional terms may apply.

Thu, Sep. 4 - Thu, Sep. 11
IAD
Washington
SEA
Seattle
CA $382 Roundtrip, found 5 days ago
CA $382
Roundtrip
found 5 days ago
Select Alaska Airlines flight, departing Thu, Sep. 4 from Washington to Seattle, returning Thu, Sep. 11, priced at CA $382 found 5 days ago
Mon, Sep. 22 - Mon, Sep. 29
IAD
Washington
SEA
Seattle
CA $391 Roundtrip, found 1 day ago
CA $391
Roundtrip
found 1 day ago
Select Alaska Airlines flight, departing Mon, Sep. 22 from Washington to Seattle, returning Mon, Sep. 29, priced at CA $391 found 1 day ago
Fri, Sep. 5 - Mon, Sep. 8
IAD
Washington
SEA
Seattle
CA $417 Roundtrip, found 4 days ago
CA $417
Roundtrip
found 4 days ago
Select Alaska Airlines flight, departing Fri, Sep. 5 from Washington to Seattle, returning Mon, Sep. 8, priced at CA $417 found 4 days ago
Mon, Sep. 22 - Mon, Sep. 29
IAD
Washington
SEA
Seattle
CA $418 Roundtrip, found 1 day ago
CA $418
Roundtrip
found 1 day ago
Select Alaska Airlines flight, departing Mon, Sep. 22 from Washington to Seattle, returning Mon, Sep. 29, priced at CA $418 found 1 day ago
Thu, Sep. 4 - Thu, Sep. 11
IAD
Washington
SEA
Seattle
CA $450 Roundtrip, found 5 days ago
CA $450
Roundtrip
found 5 days ago
Select Alaska Airlines flight, departing Thu, Sep. 4 from Washington to Seattle, returning Thu, Sep. 11, priced at CA $450 found 5 days ago
Mon, Sep. 22 - Mon, Sep. 29
IAD
Washington
SEA
Seattle
CA $460 Roundtrip, found 1 day ago
CA $460
Roundtrip
found 1 day ago
Select Alaska Airlines flight, departing Mon, Sep. 22 from Washington to Seattle, returning Mon, Sep. 29, priced at CA $460 found 1 day ago
Fri, Feb. 27 - Sat, Mar. 7
IAD
Washington
SEA
Seattle
CA $465 Roundtrip, found 1 day ago
CA $465
Roundtrip
found 1 day ago
Select Alaska Airlines flight, departing Fri, Feb. 27 from Washington to Seattle, returning Sat, Mar. 7, priced at CA $465 found 1 day ago
Thu, Jan. 22 - Wed, Jan. 28
IAD
Washington
SEA
Seattle
CA $466 Roundtrip, found 18 hours ago
CA $466
Roundtrip
found 18 hours ago
Select Alaska Airlines flight, departing Thu, Jan. 22 from Washington to Seattle, returning Wed, Jan. 28, priced at CA $466 found 18 hours ago
Mon, Sep. 22 - Mon, Sep. 29
IAD
Washington
SEA
Seattle
CA $489 Roundtrip, found 1 day ago
CA $489
Roundtrip
found 1 day ago
Select Alaska Airlines flight, departing Mon, Sep. 22 from Washington to Seattle, returning Mon, Sep. 29, priced at CA $489 found 1 day ago
Fri, Sep. 5 - Mon, Sep. 8
IAD
Washington
SEA
Seattle
CA $517 Roundtrip, found 4 days ago
CA $517
Roundtrip
found 4 days ago
Select Alaska Airlines flight, departing Fri, Sep. 5 from Washington to Seattle, returning Mon, Sep. 8, priced at CA $517 found 4 days ago

Frequently asked questions

Are there direct flights from Dulles Intl. Airport to SEA?
Sometimes, a vacation is all about the journey; sometimes the magic is in the destination. If you just want to get to Seattle fast, multiple airlines advertise direct flights from Washington Dulles Intl. Airport (IAD) to SEA, including Alaska Airlines and United Airlines.
What airlines fly from IAD to Sea-Tac Airport?
You can take your pick from a number of airlines advertising direct flights between Sterling and Seattle. Alaska Airlines (AS) is one of the most well-known. This carrier operates roughly 52 flights each month. You should also look up the deals on offer from United Airlines (UA). Another leading airline, it operates 30 flights every month on the Sterling to Seattle route. Compare the two airlines to walk away with 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.
*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.