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Cheap flights from Washington, D.C. Dulles Intl Airport to Seattle from $107

This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from Washington, D.C. Dulles Intl Airport to Seattle departing on 5/29. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.
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Find the cheapest flights from Washington, D.C. Dulles Intl Airport to Seattle

Cheap round-trip flights

These are some of the best round-trip flight deals from Washington, D.C. Dulles Intl Airport to Seattle that have been recently found on momondo from popular airlines, departing in the coming months.
Frontier Logo
7:45 am - 6:02 pmIAD-SEA
13h 17m1 stop
Frontier Logo
3:11 pm - 5:55 amSEA-IAD
11h 44m1 stop
$218Frontier
Find Deal
Fri, May 9 - Thu, May 22
Frontier Logo
7:45 am - 6:02 pmIAD-SEA
13h 17m1 stop
Frontier Logo
8:22 pm - 6:31 amSEA-IAD
31h 09m1 stop
$221Frontier
Find Deal
Fri, May 9 - Sun, May 11
Delta Logo
7:45 am - 10:33 amIAD-SEA
5h 48mnonstop
Delta Logo
9:55 pm - 5:59 amSEA-IAD
5h 04mnonstop
$237Delta
Find Deal
Tue, Jun 3 - Sat, Jun 14
Alaska Airlines Logo
6:15 pm - 9:00 pmIAD-SEA
5h 45mnonstop
Alaska Airlines Logo
5:59 pm - 5:55 amSEA-IAD
8h 56m1 stop
$247Alaska Airlines
Find Deal
Tue, Jun 3 - Tue, Jun 10
Hawaiian Airlines Logo
7:00 am - 9:40 amIAD-SEA
5h 40mnonstop
Hawaiian Airlines Logo
11:30 pm - 7:36 amSEA-IAD
5h 06mnonstop
$255Hawaiian Airlines
Find Deal
Sat, May 31 - Sat, Jun 7
Hawaiian Airlines Logo
6:15 pm - 9:00 pmIAD-SEA
5h 45mnonstop
Hawaiian Airlines Logo
4:00 pm - 11:59 pmSEA-IAD
4h 59mnonstop
$256Hawaiian Airlines
Find Deal
Tue, May 27 - Tue, Jun 3
Alaska Airlines Logo
6:15 pm - 9:00 pmIAD-SEA
5h 45mnonstop
Alaska Airlines Logo
5:59 pm - 5:55 amSEA-IAD
8h 56m1 stop
$267Alaska Airlines
Find Deal
Tue, Jun 3 - Tue, Jun 10
United Airlines Logo
5:36 pm - 10:30 pmIAD-SEA
7h 54m1 stop
United Airlines Logo
2:30 pm - 12:34 amSEA-IAD
7h 04m1 stop
$277United Airlines
Find Deal
Tue, Jun 3 - Tue, Jun 10
Delta Logo
7:40 am - 10:28 amIAD-SEA
5h 48mnonstop
Delta Logo
9:55 pm - 5:59 amSEA-IAD
5h 04mnonstop
$317Delta
Find Deal
Wed, Jun 11 - Sun, Jun 15
United Airlines Logo
10:09 pm - 12:59 amIAD-SEA
5h 50mnonstop
United Airlines Logo
12:55 pm - 9:02 pmSEA-IAD
5h 07mnonstop
$342United Airlines
Find Deal
Thu, May 22 - Wed, May 28

Frontier flights from Washington, D.C. Dulles Intl Airport to Seattle

Our best Frontier deals on Washington, D.C. Dulles Intl Airport to Seattle flight tickets
Frontier
May 9
IAD7:45 amWashington, D.C. Dulles Intl
13h 17m
1 stop
SEA6:02 pmSeattle/Tacoma Intl
May 22
SEA3:11 pmSeattle/Tacoma Intl
11h 44m
1 stop
IAD5:55 amWashington, D.C. Dulles Intl
Frontier
May 9
IAD7:45 amWashington, D.C. Dulles Intl
13h 17m
1 stop
SEA6:02 pmSeattle/Tacoma Intl
May 11
SEA8:22 pmSeattle/Tacoma Intl
31h 09m
1 stop
IAD6:31 amWashington, D.C. Dulles Intl
Frontier
May 9
IAD7:45 amWashington, D.C. Dulles Intl
13h 17m
1 stop
SEA6:02 pmSeattle/Tacoma Intl
May 11
SEA8:22 pmSeattle/Tacoma Intl
31h 09m
1 stop
IAD6:31 amWashington, D.C. Dulles Intl

Delta flights from Washington, D.C. Dulles Intl Airport to Seattle

Our best Delta deals on Washington, D.C. Dulles Intl Airport to Seattle flight tickets
Delta
Jun 3
IAD7:45 amWashington, D.C. Dulles Intl
5h 48m
SEA10:33 amSeattle/Tacoma Intl
Jun 14
SEA9:55 pmSeattle/Tacoma Intl
5h 04m
IAD5:59 amWashington, D.C. Dulles Intl
Delta
Jun 11
IAD7:40 amWashington, D.C. Dulles Intl
5h 48m
SEA10:28 amSeattle/Tacoma Intl
Jun 15
SEA9:55 pmSeattle/Tacoma Intl
5h 04m
IAD5:59 amWashington, D.C. Dulles Intl
Delta
Jun 29
IAD7:40 amWashington, D.C. Dulles Intl
5h 48m
SEA10:28 amSeattle/Tacoma Intl
Jul 9
SEA9:55 pmSeattle/Tacoma Intl
5h 02m
IAD5:57 amWashington, D.C. Dulles Intl

See travel insights to Seattle from

How to get the cheapest flight ticket from Washington, D.C. Dulles Intl Airport to Seattle

Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip

What is the cheapest month to fly to Seattle?

In general, February is the cheapest month to fly from Washington, D.C. Dulles Intl Airport to Seattle. Due to it being the ‘off-season’ during this time, you can expect flight prices to be around $347. If you don’t want to visit Seattle in February, then you should wait until January to fly from Washington, D.C. Dulles Intl Airport, when ticket prices are also cheap, with an average price of $357.

What is the cheapest day to depart on your flight to Seattle?

On average, the least expensive day to fly to Seattle from Washington, D.C. Dulles Intl Airport is on a Tuesday. momondo users have found tickets for Tuesday departures for as low as $449. However, this price may fluctuate depending on the airline, the season, and holidays. On the other hand, Sunday is the most expensive day to depart from Washington, D.C. Dulles Intl Airport because it is more convenient for both business and leisure travelers. As a result, prices tend to be around $572.

What is the cheapest time of day to depart on your flight to Seattle?

Flying to Seattle from Washington, D.C. Dulles Intl Airport in the evening is the least expensive time of day to depart. momondo users have found prices as low as $409 when looking at flights departing in the evening. Flights to Seattle are more costly in the morning, with an average ticket price of $533. Departure times in the morning fall within the peak daily travel times, which is why tickets can be more expensive.

What is the cheapest Washington, D.C. Dulles Intl to Seattle/Tacoma Intl flight route?

Fly from Washington, D.C. Dulles Intl to Seattle/Tacoma Intl for the best Washington, D.C. Dulles Intl - Seattle/Tacoma Intl flight prices

How far in advance should I book a flight to Seattle?

You are more likely to see cheaper flights to Seattle from Washington, D.C. Dulles Intl Airport when booking 7 weeks ahead of your departure date. In general, you can expect to find flights to Seattle for around $414 when searching 7 weeks out.However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Seattle from Washington, D.C. Dulles Intl Airport for as low as $365 on momondo.

What cabin class options are available on Washington, D.C. Dulles Intl to Seattle/Tacoma Intl flights?

There are 4 cabin classes available to choose from on Washington, D.C. Dulles Intl to Seattle/Tacoma Intl flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.

How have Washington, D.C. Dulles Intl Airport to Seattle flight prices changed over time?

As of April 2025, prices for Washington, D.C. Dulles Intl Airport to Seattle flights are approximately 18% cheaper when compared to flights at the same time last year.

When to book flights from Washington, D.C. Dulles Intl Airport to Seattle

Are you open to changing your travel dates? Check out the ideal times to fly from Washington, D.C. Dulles Intl Airport to Seattle according to our flight data. Find out which month and days have the cheapest flights.
Estimated round-trip price

Cheap Washington, D.C. Dulles Intl Airport to Seattle (IAD to SEA) flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from Washington, D.C. Dulles Intl Airport to Seattle

Best Price Found

$107

Fastest flight time

5h 39m

Direct flights

Every day

Airports in Seattle

1 airport
The best one-way flight to Seattle from Washington, D.C. Dulles Intl Airport in the past 72 hours is $107. The best round-trip flight deal from Washington, D.C. Dulles Intl Airport to Seattle found on momondo in the last 72 hours is $218.
The fastest flight from Washington, D.C. Dulles Intl Airport to Seattle takes 5h 39m
Direct flights go from Washington, D.C. Dulles Intl Airport to Seattle every day.
There is 1 airport near Seattle: Seattle/Tacoma Intl (SEA)

  • How far is Washington, D.C. Dulles Intl to Seattle/Tacoma Intl by plane?

    The distance between Washington, D.C. Dulles Intl and Seattle/Tacoma Intl is about 2299.7 mi. A reasonable flight in good conditions will take 5h 39m.

  • When did momondo last update prices for flights from Washington, D.C. Dulles Intl Airport to Seattle/Tacoma Intl Airport?

    Prices for flights from Washington, D.C. Dulles Intl Airport to Seattle/Tacoma Intl Airport are updated daily.

  • How many operators does momondo search for flights from Washington, D.C. Dulles Intl Airport to Seattle/Tacoma Intl Airport?

  • How old do you have to be to fly from Washington, D.C. Dulles Intl Airport to Seattle/Tacoma Intl Airport?

    The minimum age for a child to fly alone is five, but airlines that offer an unaccompanied minor (UNMR) service may have their own age limitations. Flight duration, scheduling, and layovers are among the considerations that may influence age limits. We recommend that you double-check with the airline you are booking with for travel from Washington, D.C. Dulles Intl Airport to Seattle/Tacoma Intl Airport.

  • What documentation or ID do you need to fly to Seattle/Tacoma Intl Airport?

    The travel and health documents required for your trip to Seattle/Tacoma Intl Airport can vary based on your itinerary and personal situation. As a rule, consider having multiple documents such as a national ID card or driver’s license, and a passport valid for six-months after you plan to arrive at Seattle/Tacoma Intl Airport. We always recommend checking with your airline or a trusted third party such as IATA to get advice.

  • What is the most popular plane model from Washington, D.C. Dulles Intl Airport to Seattle?

  • What is the most popular airline from Washington, D.C. Dulles Intl Airport to Seattle?


Best airlines flying from Washington, D.C. Dulles Intl Airport to Seattle

Compare and see reviews for airlines that fly from Washington, D.C. Dulles Intl Airport to Seattle with momondo
Airline
Rating
Free Cancellation
Price
Sun Country AirPriceFrom $144Free CancellationRating
6.9
345 reviews
Search Sun Country Air flights
FrontierPriceFrom $148Free CancellationRating
5.9
3,284 reviews
Search Frontier flights
Hawaiian AirlinesPriceFrom $168Free CancellationRating
7.9
2,405 reviews
Search Hawaiian Airlines flights
DeltaPriceFrom $237Free CancellationRating
8.0
7,929 reviews
Search Delta flights
Alaska AirlinesPriceFrom $260Free CancellationRating
8.0
9,961 reviews
Search Alaska Airlines flights
United AirlinesPriceFrom $285Free CancellationRating
7.4
8,696 reviews
Search United Airlines flights
American AirlinesPriceFrom $296Free CancellationRating
7.2
10,000 reviews
Search American Airlines flights
  • Delta Flights From Washington, D.C. Dulles Intl Airport to Seattle

    Across 6 Delta flights from Washington, D.C. Dulles Intl Airport to Seattle this week, the average price was $392, with the best Delta deals starting from $237 round-trip. 7,929 users have rated Delta on momondo, with an average score of 8.0/10.

  • Alaska Airlines Flights From Washington, D.C. Dulles Intl Airport to Seattle

    The best Alaska Airlines deal for Washington, D.C. Dulles Intl Airport to Seattle flight tickets found on momondo in the last 72 hours was $260, round-trip. It should be noted that an average Alaska Airlines flight deal for this route in this time was higher, at $432 round-trip. Alaska Airlines operates 8 flights out of Washington, D.C. Dulles Intl Airport into Seattle in an average week, so prices vary by time and availability. 9,961 Alaska Airlines reviews by users on momondo have scored the airline at 8.0/10.


Traveling to a place near Seattle?

Book flights to Seattle if you plan to visit one of these locations
Leavenworth
Tacoma
SeaTac
Ocean Shores
Olympia
Kent
Renton
Federal Way
Tukwila
Puyallup
Kirkland
Lakewood
Lynnwood
Fife
Shoreline
Marysville
Centralia
Redmond
Cle Elum
Lacey

Why use momondo?

Why should I use momondo to find a flight deal from Washington, D.C. to Seattle?

We help find the flight that best suits your needs, momondo compares prices from hundreds of airlines and travel agents and helps you filter them to find the best flight from Washington, D.C. to Seattle for you.

Can I find flights from Washington, D.C. to Seattle with flexible booking policies on momondo?

Yes. momondo allows you to filter the results for Washington, D.C. to Seattle flights to just show those with flexible booking policies.

How can momondo help me find flights from Washington, D.C. to Seattle?

momondo offers useful filters to help you find the right flight. Choose specific flight times, airports or even what payment method you prefer. We have numerous options to help you book your ideal flight from Washington, D.C. to Seattle.

I’m not ready to book a flight from Washington, D.C. to Seattle right now. Can momondo alert me if prices change?

Price alerts on flights to Seattle from Washington, D.C. are quick and easy to set up on momondo. Simply perform a search and select the price alert feature. It is as simple as that.


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