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 $294 round trip and CA $164 one way. Prices and availability subject to change. Additional terms may apply.

Sat, Apr 25 - Fri, May 1
IAD
Washington
SEA
Seattle
CA $294 Roundtrip, found 3 days ago
CA $294
Roundtrip
found 3 days ago
Select Alaska Airlines flight, departing Sat, Apr 25 from Washington to Seattle, returning Fri, May 1, priced at CA $294 found 3 days ago
Thu, Apr 23 - Mon, Apr 27
IAD
Washington
SEA
Seattle
CA $306 Roundtrip, found 2 days ago
CA $306
Roundtrip
found 2 days ago
Select Alaska Airlines flight, departing Thu, Apr 23 from Washington to Seattle, returning Mon, Apr 27, priced at CA $306 found 2 days ago
Sat, Apr 25 - Fri, May 1
IAD
Washington
SEA
Seattle
CA $343 Roundtrip, found 1 day ago
CA $343
Roundtrip
found 1 day ago
Select Alaska Airlines flight, departing Sat, Apr 25 from Washington to Seattle, returning Fri, May 1, priced at CA $343 found 1 day ago
Sat, Apr 25 - Fri, May 1
IAD
Washington
SEA
Seattle
CA $347 Roundtrip, found 6 days ago
CA $347
Roundtrip
found 6 days ago
Select Alaska Airlines flight, departing Sat, Apr 25 from Washington to Seattle, returning Fri, May 1, priced at CA $347 found 6 days ago
Thu, Apr 23 - Mon, Apr 27
IAD
Washington
SEA
Seattle
CA $373 Roundtrip, found 2 days ago
CA $373
Roundtrip
found 2 days ago
Select Alaska Airlines flight, departing Thu, Apr 23 from Washington to Seattle, returning Mon, Apr 27, priced at CA $373 found 2 days ago
Thu, Apr 9 - Mon, Apr 13
IAD
Washington
SEA
Seattle
CA $373 Roundtrip, found 6 days ago
CA $373
Roundtrip
found 6 days ago
Select Alaska Airlines flight, departing Thu, Apr 9 from Washington to Seattle, returning Mon, Apr 13, priced at CA $373 found 6 days ago
Sat, May 2 - Fri, May 8
IAD
Washington
SEA
Seattle
CA $374 Roundtrip, found 6 days ago
CA $374
Roundtrip
found 6 days ago
Select Alaska Airlines flight, departing Sat, May 2 from Washington to Seattle, returning Fri, May 8, priced at CA $374 found 6 days ago
Fri, Apr 24 - Mon, Apr 27
IAD
Washington
SEA
Seattle
CA $400 Roundtrip, found 2 days ago
CA $400
Roundtrip
found 2 days ago
Select Alaska Airlines flight, departing Fri, Apr 24 from Washington to Seattle, returning Mon, Apr 27, priced at CA $400 found 2 days ago
Fri, Apr 24 - Mon, Apr 27
IAD
Washington
SEA
Seattle
CA $407 Roundtrip, found 2 days ago
CA $407
Roundtrip
found 2 days ago
Select Alaska Airlines flight, departing Fri, Apr 24 from Washington to Seattle, returning Mon, Apr 27, priced at CA $407 found 2 days ago
Fri, May 1 - Thu, May 7
IAD
Washington
SEA
Seattle
CA $411 Roundtrip, found 4 days ago
CA $411
Roundtrip
found 4 days ago
Select Alaska Airlines flight, departing Fri, May 1 from Washington to Seattle, returning Thu, May 7, priced at CA $411 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.

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*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.