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Cheap flights from Washington, D.C. Dulles Intl Airport to Seattle from $109

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 2/24. 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.

Cheap one-way flights

Flying one-way? These are some of the best deals recently discovered on momondo for flights from Washington, D.C. Dulles Intl Airport to Seattle.

Cheap last minute flights

Planning a quick getaway from Washington, D.C. Dulles Intl Airport to Seattle? These are the last-minute flight deals available now.

Cheap direct flights

If you prefer a non-stop journey, check out our latest direct flight deals to Seattle, so you can enjoy a seamless trip without layovers.

Cheap bus & train deals from Washington, D.C. Dulles Intl Airport to Seattle

Find recent round-trip train or bus tickets from Washington, D.C. Dulles Intl Airport to Seattle.

All round-trip flight deals to Seattle

The cheapest plane tickets to Seattle found on KAYAK recently.
6:57 pm - 10:00 pmIAD-SEA
6h 03mnonstop
9:54 am - 5:57 pmSEA-IAD
5h 03mnonstop
$277Alaska Airlines
Find Deal
Wed, Feb 5 - Tue, Feb 11
4:05 pm - 7:06 pmIAD-SEA
6h 01mnonstop
7:10 am - 3:10 pmSEA-IAD
5h 00mnonstop
$282Delta
Find Deal
Wed, Feb 5 - Mon, Feb 10
5:30 pm - 8:31 pmIAD-SEA
6h 01mnonstop
7:00 am - 8:40 pmSEA-IAD
10h 40m1 stop
$283United Airlines
Find Deal
Wed, Jan 29 - Sat, Feb 1
4:05 pm - 7:06 pmIAD-SEA
6h 01mnonstop
7:28 am - 3:28 pmSEA-IAD
5h 00mnonstop
$287Delta
Find Deal
Thu, Feb 6 - Thu, Feb 13
5:30 pm - 8:31 pmIAD-SEA
6h 01mnonstop
7:00 am - 8:40 pmSEA-IAD
10h 40m1 stop
$288United Airlines
Find Deal
Sat, Feb 1 - Sun, Feb 9
5:25 pm - 9:30 amIAD-SEA
19h 05m1 stop
9:54 am - 5:57 pmSEA-IAD
5h 03mnonstop
$292Alaska Airlines
Find Deal
Sat, Feb 1 - Thu, Feb 6
1:52 pm - 9:18 pmIAD-SEA
10h 26m1 stop
5:22 am - 4:14 pmSEA-IAD
7h 52m1 stop
$298American Airlines
Find Deal
Sat, Feb 1 - Sat, Feb 8
1:52 pm - 11:31 pmIAD-SEA
12h 39m2 stops
5:22 am - 4:14 pmSEA-IAD
7h 52m1 stop
$304American Airlines
Find Deal
Sat, Feb 1 - Sat, Feb 8
11:05 am - 10:51 pmIAD-SEA
14h 46m1 stop
11:59 pm - 11:07 amSEA-IAD
8h 08m1 stop
$320Sun Country Air
Find Deal
Thu, Apr 3 - Sun, Apr 6
12:45 pm - 10:51 pmIAD-SEA
13h 06m1 stop
6:40 pm - 11:43 amSEA-IAD
14h 03m1 stop
$356Sun Country Air
Find Deal
Fri, May 30 - Wed, Jun 11
9:13 pm - 2:44 pmIAD-SEA
20h 31m2 stops
$109Frontier
Find Deal
Mon, Feb 24
4:05 pm - 7:06 pmIAD-SEA
6h 01mnonstop
$137Delta
Find Deal
Wed, Jan 29
7:00 am - 9:56 amIAD-SEA
5h 56mnonstop
$139Alaska Airlines
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Wed, Feb 26
12:45 pm - 5:27 pmIAD-SEA
7h 42m1 stop
$145Sun Country Air
Find Deal
Thu, May 1
7:00 am - 1:17 pmIAD-SEA
9h 17m1 stop
$148Alaska Airlines
Find Deal
Wed, Mar 19
6:17 pm - 12:55 amIAD-SEA
9h 38m1 stop
$149United Airlines
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Wed, Feb 26
10:05 am - 6:15 pmIAD-SEA
11h 10m1 stop
$154United Airlines
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Fri, Feb 7
11:20 am - 4:52 pmIAD-SEA
8h 32m1 stop
$155Sun Country Air
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Fri, Apr 25
5:00 am - 12:42 pmIAD-SEA
10h 42m2 stops
$159American Airlines
Find Deal
Fri, Feb 7
5:13 pm - 11:19 pmIAD-SEA
9h 06m1 stop
$179American Airlines
Find Deal
Sun, Mar 2
8:20 am - 10:00 pmIAD-SEA
16h 40m2 stops
5:00 am - 11:30 pmSEA-IAD
15h 30m1 stop
$638United Airlines
Find Deal
Mon, Jan 13 - Fri, Jan 17
4:05 pm - 7:06 pmIAD-SEA
6h 01mnonstop
7:10 am - 3:10 pmSEA-IAD
5h 00mnonstop
$653Delta
Find Deal
Fri, Jan 10 - Wed, Jan 22
6:05 am - 10:45 amIAD-SEA
7h 40m1 stop
7:10 am - 3:10 pmSEA-IAD
5h 00mnonstop
$663Delta
Find Deal
Fri, Jan 10 - Wed, Jan 22
5:25 pm - 9:30 amIAD-SEA
19h 05m1 stop
9:16 pm - 4:23 pmSEA-IAD
16h 07m1 stop
$672Alaska Airlines
Find Deal
Fri, Jan 10 - Wed, Jan 22
5:24 pm - 11:31 pmIAD-SEA
9h 07m1 stop
5:22 am - 7:35 pmSEA-IAD
11h 13m2 stops
$678American Airlines
Find Deal
Fri, Jan 10 - Wed, Jan 22
1:53 pm - 11:31 pmIAD-SEA
12h 38m2 stops
5:22 am - 7:35 pmSEA-IAD
11h 13m2 stops
$683American Airlines
Find Deal
Fri, Jan 10 - Wed, Jan 22
8:20 am - 10:00 pmIAD-SEA
16h 40m2 stops
12:35 pm - 11:23 amSEA-IAD
19h 48m1 stop
$718United Airlines
Find Deal
Sat, Jan 11 - Tue, Jan 14
5:25 pm - 9:30 amIAD-SEA
19h 05m1 stop
7:50 pm - 4:23 pmSEA-IAD
17h 33m1 stop
$762Alaska Airlines
Find Deal
Sat, Jan 11 - Tue, Jan 14
3:55 pm - 10:30 pmIAD-SEA
9h 35m1 stop
5:05 am - 2:40 pmSEA-IAD
6h 35m1 stop
$763Southwest
Find Deal
Mon, Jan 13 - Thu, Jan 16
6:55 am - 5:25 pmIAD-SEA
13h 30m2 stops
9:45 am - 11:20 pmSEA-IAD
10h 35m1 stop
$768Southwest
Find Deal
Sun, Jan 12 - Fri, Jan 17
4:05 pm - 7:06 pmIAD-SEA
6h 01mnonstop
7:10 am - 3:10 pmSEA-IAD
5h 00mnonstop
$277Delta
Find Deal
Wed, Feb 5 - Wed, Feb 12
4:05 pm - 7:06 pmIAD-SEA
6h 01mnonstop
7:10 am - 3:10 pmSEA-IAD
5h 00mnonstop
$282Delta
Find Deal
Thu, Jan 30 - Sat, Feb 1
4:05 pm - 7:06 pmIAD-SEA
6h 01mnonstop
7:10 am - 3:10 pmSEA-IAD
5h 00mnonstop
$287Delta
Find Deal
Thu, Feb 6 - Mon, Feb 10
10:00 am - 12:40 pmIAD-SEA
5h 40mnonstop
9:55 pm - 5:55 amSEA-IAD
5h 00mnonstop
$292Alaska Airlines
Find Deal
Tue, May 13 - Tue, May 20
5:35 pm - 8:26 pmIAD-SEA
5h 51mnonstop
8:00 am - 3:53 pmSEA-IAD
4h 53mnonstop
$296United Airlines
Find Deal
Sat, May 10 - Sun, May 25
5:25 pm - 8:24 pmIAD-SEA
5h 59mnonstop
8:10 am - 4:09 pmSEA-IAD
4h 59mnonstop
$298United Airlines
Find Deal
Fri, Mar 7 - Wed, Mar 12
5:25 pm - 8:24 pmIAD-SEA
5h 59mnonstop
8:10 am - 4:09 pmSEA-IAD
4h 59mnonstop
$303United Airlines
Find Deal
Fri, Mar 7 - Mon, Mar 10
7:00 am - 9:56 amIAD-SEA
5h 56mnonstop
9:50 am - 5:48 pmSEA-IAD
4h 58mnonstop
$327Alaska Airlines
Find Deal
Tue, Mar 11 - Sat, Mar 15
7:00 am - 9:56 amIAD-SEA
5h 56mnonstop
9:50 am - 5:48 pmSEA-IAD
4h 58mnonstop
$332Alaska Airlines
Find Deal
Sun, Feb 23 - Sat, Mar 1
6:57 pm - 10:00 pmIAD-SEA
6h 03mnonstop
8:00 am - 4:06 pmSEA-IAD
5h 06mnonstop
$336Alaska Airlines
Find Deal
Mon, Jan 27 - Wed, Feb 5

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

Our best Alaska Airlines deals on Washington, D.C. Dulles Intl Airport to Seattle flight tickets
Alaska Airlines
Feb 5
IAD6:57 pmWashington, D.C. Dulles Intl
6h 03m
SEA10:00 pmSeattle/Tacoma Intl
Feb 11
SEA9:54 amSeattle/Tacoma Intl
5h 03m
IAD5:57 pmWashington, D.C. Dulles Intl
Alaska Airlines
Feb 1
IAD5:25 pmWashington, D.C. Dulles Intl
19h 05m
1 stop
SEA9:30 amSeattle/Tacoma Intl
Feb 6
SEA9:54 amSeattle/Tacoma Intl
5h 03m
IAD5:57 pmWashington, D.C. Dulles Intl
Alaska Airlines
Apr 1
IAD7:31 amWashington, D.C. Dulles Intl
38h 30m
2 stops
SEA7:01 pmSeattle/Tacoma Intl
Apr 2
SEA9:40 pmSeattle/Tacoma Intl
4h 54m
IAD5:34 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
Feb 5
IAD4:05 pmWashington, D.C. Dulles Intl
6h 01m
SEA7:06 pmSeattle/Tacoma Intl
Feb 10
SEA7:10 amSeattle/Tacoma Intl
5h 00m
IAD3:10 pmWashington, D.C. Dulles Intl
Delta
Feb 6
IAD4:05 pmWashington, D.C. Dulles Intl
6h 01m
SEA7:06 pmSeattle/Tacoma Intl
Feb 13
SEA7:28 amSeattle/Tacoma Intl
5h 00m
IAD3:28 pmWashington, D.C. Dulles Intl
Delta
Feb 28
IAD4:23 pmWashington, D.C. Dulles Intl
6h 01m
SEA7:24 pmSeattle/Tacoma Intl
Mar 3
SEA7:28 amSeattle/Tacoma Intl
5h 00m
IAD3:28 pmWashington, 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, January 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 January, then you should wait until February to fly from Washington, D.C. Dulles Intl Airport, when ticket prices are also cheap, with an average price of $352.

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 $396. 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 $476.

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

Flying to Seattle from Washington, D.C. Dulles Intl Airport at noon is the least expensive time of day to depart. momondo users have found prices as low as $326 when looking at flights departing at noon. Flights to Seattle are more costly in the morning, with an average ticket price of $455. 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 40 days ahead of your departure date. In general, you can expect to find flights to Seattle for around $406 when searching 40 days out. Keep in mind that you might be able to find cheaper flights to Seattle at any time. In fact, our users found flights for as low as $306 in the past 72 hours.

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 January 2025, prices for Washington, D.C. Dulles Intl Airport to Seattle flights are approximately 8% more expensive 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

$109

Fastest flight time

5h 35m

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 $109. The best round-trip flight deal from Washington, D.C. Dulles Intl Airport to Seattle found on momondo in the last 72 hours is $277.
The fastest flight from Washington, D.C. Dulles Intl Airport to Seattle takes 5h 35m
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 35m.

  • 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
7.0
379 reviews
Search Sun Country Air flights
DeltaPriceFrom $185Free CancellationRating
8.0
8,499 reviews
Search Delta flights
Alaska AirlinesPriceFrom $222Free CancellationRating
8.0
9,627 reviews
Search Alaska Airlines flights
American AirlinesPriceFrom $254Free CancellationRating
7.2
10,000 reviews
Search American Airlines flights
United AirlinesPriceFrom $273Free CancellationRating
7.4
8,938 reviews
Search United Airlines flights
  • Delta Flights From Washington, D.C. Dulles Intl Airport to Seattle

    Across 7 Delta flights from Washington, D.C. Dulles Intl Airport to Seattle this week, the average price was $395, with the best Delta deals starting from $185 round-trip. 8,499 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 $222, round-trip. It should be noted that an average Alaska Airlines flight deal for this route in this time was higher, at $426 round-trip. Alaska Airlines operates 2 flights out of Washington, D.C. Dulles Intl Airport into Seattle in an average week, so prices vary by time and availability. 9,627 Alaska Airlines reviews by users on momondo have scored the airline at 8.0/10.


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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