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 $223 round trip and CA $142 one way. Prices and availability subject to change. Additional terms may apply.

Thu, Jan 22 - Tue, Feb 3
SEA
Seattle
IAD
Washington
CA $223 Roundtrip, found 1 day ago
CA $223
Roundtrip
found 1 day ago
Select Delta flight, departing Thu, Jan 22 from Seattle to Washington, returning Tue, Feb 3, priced at CA $223 found 1 day ago
Thu, Jan 22 - Wed, Jan 28
SEA
Seattle
IAD
Washington
CA $224 Roundtrip, found 1 day ago
CA $224
Roundtrip
found 1 day ago
Select Alaska Airlines flight, departing Thu, Jan 22 from Seattle to Washington, returning Wed, Jan 28, priced at CA $224 found 1 day ago
Thu, Jan 29 - Wed, Feb 4
SEA
Seattle
IAD
Washington
CA $225 Roundtrip, found 3 hours ago
CA $225
Roundtrip
found 3 hours ago
Select Alaska Airlines flight, departing Thu, Jan 29 from Seattle to Washington, returning Wed, Feb 4, priced at CA $225 found 3 hours ago
Mon, Jan 19 - Tue, Feb 3
SEA
Seattle
IAD
Washington
CA $228 Roundtrip, found 1 day ago
CA $228
Roundtrip
found 1 day ago
Select Delta flight, departing Mon, Jan 19 from Seattle to Washington, returning Tue, Feb 3, priced at CA $228 found 1 day ago
Thu, Jan 22 - Fri, Feb 6
SEA
Seattle
IAD
Washington
CA $236 Roundtrip, found 1 day ago
CA $236
Roundtrip
found 1 day ago
Select Delta flight, departing Thu, Jan 22 from Seattle to Washington, returning Fri, Feb 6, priced at CA $236 found 1 day ago
Mon, Jan 19 - Fri, Feb 6
SEA
Seattle
IAD
Washington
CA $241 Roundtrip, found 1 day ago
CA $241
Roundtrip
found 1 day ago
Select Delta flight, departing Mon, Jan 19 from Seattle to Washington, returning Fri, Feb 6, priced at CA $241 found 1 day ago
Sat, Feb 7 - Sun, Feb 8
SEA
Seattle
IAD
Washington
CA $256 Roundtrip, found 1 day ago
CA $256
Roundtrip
found 1 day ago
Select Alaska Airlines flight, departing Sat, Feb 7 from Seattle to Washington, returning Sun, Feb 8, priced at CA $256 found 1 day ago
Tue, Jan 27 - Fri, Feb 13
SEA
Seattle
IAD
Washington
CA $279 Roundtrip, found 1 day ago
CA $279
Roundtrip
found 1 day ago
Select Hawaiian Airlines flight, departing Tue, Jan 27 from Seattle to Washington, returning Fri, Feb 13, priced at CA $279 found 1 day ago
Fri, Mar 6 - Mon, Mar 9
SEA
Seattle
IAD
Washington
CA $279 Roundtrip, found 1 day ago
CA $279
Roundtrip
found 1 day ago
Select Alaska Airlines flight, departing Fri, Mar 6 from Seattle to Washington, returning Mon, Mar 9, priced at CA $279 found 1 day ago
Mon, Jan 5 - Tue, Jan 20
SEA
Seattle
IAD
Washington
CA $285 Roundtrip, found 1 day ago
CA $285
Roundtrip
found 1 day ago
Select Hawaiian Airlines flight, departing Mon, Jan 5 from Seattle to Washington, returning Tue, Jan 20, priced at CA $285 found 1 day ago

Washington Dulles Intl. flight + hotel packages - economy flights

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

Hamilton Hotel Washington DC

4 out of 5
Price was CA $655, price is now CA $489 per person
CA $489
per person
Jan 16 - Jan 20
found 1 day ago
Roundtrip flight included
Seattle (SEA) to Washington (DCA)
Sofitel Washington DC Lafayette Square

Sofitel Washington DC Lafayette Square

5 out of 5
Price was CA $966, price is now CA $560 per person
CA $560
per person
Jan 16 - Jan 20
found 1 day ago
Roundtrip flight included
Seattle (SEA) to Washington (DCA)
Hotel Arboretum

Hotel Arboretum

2 out of 5
Price was CA $785, price is now CA $511 per person
CA $511
per person
Jan 16 - Jan 20
found 1 day ago
Roundtrip flight included
Seattle (SEA) to Washington (DCA)
Crowne Plaza Crystal City-Washington, D.C. by IHG

Crowne Plaza Crystal City-Washington, D.C. by IHG

3.5 out of 5
Price was CA $713, price is now CA $512 per person
CA $512
per person
Jan 16 - Jan 20
found 1 day ago
Roundtrip flight included
Seattle (SEA) to Washington (DCA)
Embassy Suites by Hilton Washington D.C. – Convention Center

Embassy Suites by Hilton Washington D.C. – Convention Center

3.5 out of 5
Price was CA $761, price is now CA $592 per person
CA $592
per person
Jan 16 - Jan 20
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.