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

Wander Wisely with exceptional service, 24/7 supportOpens in a new window

Feel at ease with free flight cancellations within 24 hours of booking

Change your flight without a fee on select flights

Find The Best Dates To Fly

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

The cheapest flights to Washington Dulles Intl. found within the past 7 days were CA $268 round trip and CA $166 one way. Prices and availability subject to change. Additional terms may apply.

Tue, Mar 10 - Sun, Mar 15
SEA
Seattle
IAD
Washington
CA $268 Roundtrip, found 1 day ago
CA $268
Roundtrip
found 1 day ago
Select Delta flight, departing Tue, Mar 10 from Seattle to Washington, returning Sun, Mar 15, priced at CA $268 found 1 day ago
Thu, Mar 12 - Sun, Mar 15
SEA
Seattle
IAD
Washington
CA $275 Roundtrip, found 1 day ago
CA $275
Roundtrip
found 1 day ago
Select Delta flight, departing Thu, Mar 12 from Seattle to Washington, returning Sun, Mar 15, priced at CA $275 found 1 day ago
Mon, Mar 9 - Sun, Mar 15
SEA
Seattle
IAD
Washington
CA $281 Roundtrip, found 1 day ago
CA $281
Roundtrip
found 1 day ago
Select Delta flight, departing Mon, Mar 9 from Seattle to Washington, returning Sun, Mar 15, priced at CA $281 found 1 day ago
Thu, Mar 12 - Sun, Mar 15
SEA
Seattle
IAD
Washington
CA $288 Roundtrip, found 1 day ago
CA $288
Roundtrip
found 1 day ago
Select Delta flight, departing Thu, Mar 12 from Seattle to Washington, returning Sun, Mar 15, priced at CA $288 found 1 day ago
Tue, Mar 10 - Sat, Mar 14
SEA
Seattle
IAD
Washington
CA $323 Roundtrip, found 1 day ago
CA $323
Roundtrip
found 1 day ago
Select Hawaiian Airlines flight, departing Tue, Mar 10 from Seattle to Washington, returning Sat, Mar 14, priced at CA $323 found 1 day ago
Thu, Mar 5 - Wed, Mar 11
SEA
Seattle
IAD
Washington
CA $332 Roundtrip, found 6 days ago
CA $332
Roundtrip
found 6 days ago
Select Alaska Airlines flight, departing Thu, Mar 5 from Seattle to Washington, returning Wed, Mar 11, priced at CA $332 found 6 days ago
Mon, Mar 9 - Thu, Mar 12
SEA
Seattle
IAD
Washington
CA $336 Roundtrip, found 1 day ago
CA $336
Roundtrip
found 1 day ago
Select Delta flight, departing Mon, Mar 9 from Seattle to Washington, returning Thu, Mar 12, priced at CA $336 found 1 day ago
Tue, Mar 10 - Mon, Mar 16
SEA
Seattle
IAD
Washington
CA $350 Roundtrip, found 1 day ago
CA $350
Roundtrip
found 1 day ago
Select Hawaiian Airlines flight, departing Tue, Mar 10 from Seattle to Washington, returning Mon, Mar 16, priced at CA $350 found 1 day ago
Tue, Apr 21 - Sat, Apr 25
SEA
Seattle
IAD
Washington
CA $355 Roundtrip, found 5 days ago
CA $355
Roundtrip
found 5 days ago
Select Alaska Airlines flight, departing Tue, Apr 21 from Seattle to Washington, returning Sat, Apr 25, priced at CA $355 found 5 days ago
Thu, Mar 19 - Sun, Mar 22
SEA
Seattle
IAD
Washington
CA $358 Roundtrip, found 6 hours ago
CA $358
Roundtrip
found 6 hours ago
Select Alaska Airlines flight, departing Thu, Mar 19 from Seattle to Washington, returning Sun, Mar 22, priced at CA $358 found 6 hours ago

Washington Dulles Intl. flight + hotel packages - economy flights

Price found within the past 48 hours. Click for updated prices.
Arlo Washington DC

Arlo Washington DC

4 out of 5
Price was CA $2,718, price is now CA $1,865 per person
CA $1,865
per person
Mar 21 - Mar 27
found 1 day ago
Roundtrip flight included
Seattle (SEA) to Washington (DCA)
Eurostars Saint Gregory Dupont Circle Georgetown

Eurostars Saint Gregory Dupont Circle Georgetown

4 out of 5
Price was CA $2,977, price is now CA $1,878 per person
CA $1,878
per person
Mar 21 - Mar 27
found 1 day ago
Roundtrip flight included
Seattle (SEA) to Washington (DCA)
Placemakr Buzzard Point

Placemakr Buzzard Point

2.5 out of 5
Price was CA $3,193, price is now CA $2,452 per person
CA $2,452
per person
Mar 21 - Mar 27
found 1 day ago
Roundtrip flight included
Seattle (SEA) to Washington (DCA)
Hampton Inn & Suites Washington DC-Navy Yard

Hampton Inn & Suites Washington DC-Navy Yard

3 out of 5
Price was CA $2,753, price is now CA $2,115 per person
CA $2,115
per person
Mar 21 - Mar 27
found 1 day ago
Roundtrip flight included
Seattle (SEA) to Washington (DCA)
Hilton Arlington National Landing

Hilton Arlington National Landing

4 out of 5
Price was CA $2,416, price is now CA $1,866 per person
CA $1,866
per person
Mar 21 - Mar 27
found 1 day ago
Roundtrip flight included
Seattle (SEA) to Washington (DCA)
Don't see what you're looking for?
See all available trips from Seattle - Tacoma Intl. to Washington Dulles Intl.
View all trips

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.