Cheap flights from Seattle to Washington, D.C. from $169

1 adult
1 adult, Economy, 0 bags

Discover deals from 900+ travel sites with momondo.

Find the cheapest flights from Seattle to Washington, D.C.

Cheap round-trip flights

Enter your travel dates to find the best prices.
Alaska Airlines Logo
8:15 am - 4:15 pmSEA  Seattle/Tacoma Intl-IAD Washington, D.C. Dulles Intl
5h 00mnonstop
Alaska Airlines Logo
5:18 pm - 8:27 pmIAD  Washington, D.C. Dulles Intl-SEA Seattle/Tacoma Intl
6h 09mnonstop
$297Alaska Airlines
Thu, Dec 3 - Sun, Dec 6
Delta Logo
4:30 pm - 12:31 amSEA  Seattle/Tacoma Intl-IAD Washington, D.C. Dulles Intl
5h 01mnonstop
Delta Logo
7:00 am - 10:10 amIAD  Washington, D.C. Dulles Intl-SEA Seattle/Tacoma Intl
6h 10mnonstop
$297Delta
Thu, Dec 10 - Sun, Dec 13
Delta Logo
4:30 pm - 12:31 amSEA  Seattle/Tacoma Intl-IAD Washington, D.C. Dulles Intl
5h 01mnonstop
Delta Logo
7:00 am - 10:10 amIAD  Washington, D.C. Dulles Intl-SEA Seattle/Tacoma Intl
6h 10mnonstop
$298Delta
Thu, Dec 3 - Wed, Dec 9
United Airlines Logo
8:09 am - 4:08 pmSEA  Seattle/Tacoma Intl-IAD Washington, D.C. Dulles Intl
4h 59mnonstop
United Airlines Logo
3:14 pm - 9:58 pmIAD  Washington, D.C. Dulles Intl-SEA Seattle/Tacoma Intl
9h 44m1 stop Los Angeles
$303United Airlines
Wed, Dec 2 - Wed, Dec 9
United Airlines Logo
8:09 am - 4:08 pmSEA  Seattle/Tacoma Intl-IAD Washington, D.C. Dulles Intl
4h 59mnonstop
United Airlines Logo
3:14 pm - 9:58 pmIAD  Washington, D.C. Dulles Intl-SEA Seattle/Tacoma Intl
9h 44m1 stop Los Angeles
$303United Airlines
Wed, Dec 2 - Tue, Dec 8
American Airlines Logo
11:16 am - 10:05 pmSEA  Seattle/Tacoma Intl-IAD Washington, D.C. Dulles Intl
7h 49m1 stop Charlotte Douglas
American Airlines Logo
6:00 am - 3:50 pmIAD  Washington, D.C. Dulles Intl-SEA Seattle/Tacoma Intl
12h 50m1 stop Los Angeles
$317American Airlines
Thu, Dec 3 - Wed, Dec 9
American Airlines Logo
12:37 pm - 11:30 pmSEA  Seattle/Tacoma Intl-IAD Washington, D.C. Dulles Intl
7h 53m1 stop Dallas/Fort Worth
American Airlines Logo
7:18 am - 2:44 pmIAD  Washington, D.C. Dulles Intl-SEA Seattle/Tacoma Intl
10h 26m1 stop Dallas/Fort Worth
$317American Airlines
Thu, Dec 10 - Tue, Dec 15
Alaska Airlines Logo
8:15 am - 4:15 pmSEA  Seattle/Tacoma Intl-IAD Washington, D.C. Dulles Intl
5h 00mnonstop
Alaska Airlines Logo
6:42 pm - 9:32 amIAD  Washington, D.C. Dulles Intl-SEA Seattle/Tacoma Intl
17h 50m1 stop San Diego
$327Alaska Airlines
Wed, Dec 9 - Fri, Dec 11
Frontier Logo
8:56 pm - 8:10 pmSEA  Seattle/Tacoma Intl-IAD Washington, D.C. Dulles Intl
20h 14m2 stops Las Vegas Harry Reid Intl Dallas/Fort Worth
Frontier Logo
8:51 pm - 10:38 amIAD  Washington, D.C. Dulles Intl-SEA Seattle/Tacoma Intl
16h 47m1 stop Las Vegas Harry Reid Intl
$336Frontier
Mon, Dec 14 - Mon, Jan 4
Frontier Logo
9:13 pm - 5:10 amSEA  Seattle/Tacoma Intl-IAD Washington, D.C. Dulles Intl
28h 57m1 stop Las Vegas Harry Reid Intl
Frontier Logo
1:09 pm - 12:37 pmIAD  Washington, D.C. Dulles Intl-SEA Seattle/Tacoma Intl
26h 28m1 stop Las Vegas Harry Reid Intl
$338Frontier
Thu, Nov 19 - Thu, Nov 26

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

Our best Alaska Airlines deals on Seattle to Washington, D.C. Dulles Intl Airport flight tickets
Alaska Airlines
Dec 3
SEA8:15 amSeattle/Tacoma Intl
5h 00m
IAD4:15 pmWashington, D.C. Dulles Intl
Dec 6
IAD5:18 pmWashington, D.C. Dulles Intl
6h 09m
SEA8:27 pmSeattle/Tacoma Intl
$297
Alaska Airlines
Dec 3
SEA9:40 pmSeattle/Tacoma Intl
4h 55m
IAD5:35 amWashington, D.C. Dulles Intl
Dec 4
IAD6:42 pmWashington, D.C. Dulles Intl
17h 50m
1 stop
SEA9:32 amSeattle/Tacoma Intl
$327
Alaska Airlines
Dec 13
SEA8:15 amSeattle/Tacoma Intl
5h 00m
IAD4:15 pmWashington, D.C. Dulles Intl
Dec 20
IAD7:05 amWashington, D.C. Dulles Intl
5h 55m
SEA10:00 amSeattle/Tacoma Intl
$333

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

Our best Delta deals on Seattle to Washington, D.C. Dulles Intl Airport flight tickets
Delta
Dec 3
SEA4:30 pmSeattle/Tacoma Intl
5h 01m
IAD12:31 amWashington, D.C. Dulles Intl
Dec 9
IAD7:00 amWashington, D.C. Dulles Intl
6h 10m
SEA10:10 amSeattle/Tacoma Intl
$298
Delta
Dec 3
SEA4:30 pmSeattle/Tacoma Intl
5h 01m
IAD12:31 amWashington, D.C. Dulles Intl
Dec 9
IAD7:00 amWashington, D.C. Dulles Intl
6h 10m
SEA10:10 amSeattle/Tacoma Intl
$299
Delta
Dec 3
SEA1:25 pmSeattle/Tacoma Intl
7h 22m
1 stop
IAD11:47 pmWashington, D.C. Dulles Intl
Dec 6
IAD7:00 amWashington, D.C. Dulles Intl
6h 10m
SEA10:10 amSeattle/Tacoma Intl
$307

momondo Fare Finder

 
Use the filters below to find and compare flights from Seattle to Washington, D.C. Dulles Intl Airport that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip
Quickest round-trip

SeattleWashington, D.C.

SEA Seattle/Tacoma Intl - IAD Washington, D.C. Dulles Intl

SEAIAD

Seattle/Tacoma Intl

Thu 12/3

8:15 am-4:15 pm

Nonstop5h 00m

Washington, D.C. Dulles Intl

Sun 12/6

5:18 pm-8:27 pm

Nonstop6h 09m

$297

SeattleWashington, D.C.

SEA Seattle/Tacoma Intl - IAD Washington, D.C. Dulles Intl

SEAIAD

Seattle/Tacoma Intl

Thu 12/10

4:30 pm-12:31 am

Nonstop5h 01m

Washington, D.C. Dulles Intl

Sun 12/13

7:00 am-10:10 am

Nonstop6h 10m

$297

SeattleWashington, D.C.

SEA Seattle/Tacoma Intl - IAD Washington, D.C. Dulles Intl

SEAIAD

Seattle/Tacoma Intl

Thu 12/3

4:30 pm-12:31 am

Nonstop5h 01m

Washington, D.C. Dulles Intl

Wed 12/9

7:00 am-10:10 am

Nonstop6h 10m

$298

SeattleWashington, D.C.

SEA Seattle/Tacoma Intl - IAD Washington, D.C. Dulles Intl

SEAIAD

Seattle/Tacoma Intl

Wed 12/2

8:09 am-4:08 pm

Nonstop4h 59m

Washington, D.C. Dulles Intl

Wed 12/9

3:14 pm-9:58 pm

1 stop9h 44m

$303

SeattleWashington, D.C.

SEA Seattle/Tacoma Intl - IAD Washington, D.C. Dulles Intl

SEAIAD

Seattle/Tacoma Intl

Wed 12/2

8:09 am-4:08 pm

Nonstop4h 59m

Washington, D.C. Dulles Intl

Tue 12/8

3:14 pm-9:58 pm

1 stop9h 44m

$303

SeattleWashington, D.C.

SEA Seattle/Tacoma Intl - IAD Washington, D.C. Dulles Intl

SEAIAD

Seattle/Tacoma Intl

Thu 12/3

11:16 am-10:05 pm

1 stop7h 49m

Washington, D.C. Dulles Intl

Wed 12/9

6:00 am-3:50 pm

1 stop12h 50m

$317

SeattleWashington, D.C.

SEA Seattle/Tacoma Intl - IAD Washington, D.C. Dulles Intl

SEAIAD

Seattle/Tacoma Intl

Thu 12/10

12:37 pm-11:30 pm

1 stop7h 53m

Washington, D.C. Dulles Intl

Tue 12/15

7:18 am-2:44 pm

1 stop10h 26m

$317

SeattleWashington, D.C.

SEA Seattle/Tacoma Intl - IAD Washington, D.C. Dulles Intl

SEAIAD

Seattle/Tacoma Intl

Wed 12/9

8:15 am-4:15 pm

Nonstop5h 00m

Washington, D.C. Dulles Intl

Fri 12/11

6:42 pm-9:32 am

1 stop17h 50m

$327

SeattleWashington, D.C.

SEA Seattle/Tacoma Intl - IAD Washington, D.C. Dulles Intl

SEAIAD

Seattle/Tacoma Intl

Mon 12/14

8:56 pm-8:10 pm

2 stops20h 14m

Washington, D.C. Dulles Intl

Mon 1/4

8:51 pm-10:38 am

1 stop16h 47m

$336

SeattleWashington, D.C.

SEA Seattle/Tacoma Intl - IAD Washington, D.C. Dulles Intl

SEAIAD

Seattle/Tacoma Intl

Thu 11/19

9:13 pm-5:10 am

1 stop28h 57m

Washington, D.C. Dulles Intl

Thu 11/26

1:09 pm-12:37 pm

1 stop26h 28m

$338

Flights are sorted by cheapest round-trip flights first.

Showing 1-10 of 20 resultsSorted by cheapest first
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See travel insights to Washington, D.C. from

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

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 typical price of a round-trip flight between Seattle and Washington, D.C. Dulles Intl Airport?

Prices are currently low for flights on this route.

Typical prices usually range from $397 to $742.
The lowest price recently found on this route was $297.

What is the cheapest month to fly to Washington, D.C. Dulles Intl Airport?

In general, February is the cheapest month to fly from Seattle to Washington, D.C. Dulles Intl Airport. Due to it being the ‘off-season’ during this time, you can expect flight prices to be around $309. If you aren’t able to travel to Washington, D.C. Dulles Intl Airport during the month of February, then flying in April is also cheap. Prices for this month can be found on momondo for an average of $347.

What is the cheapest day to depart on your flight to Washington, D.C. Dulles Intl Airport?

Our data shows that Thursday is the least expensive day to fly to Washington, D.C. Dulles Intl Airport. Tickets to fly out on this day can be as low as $471. When flying out on a Monday, the most expensive travel day of the week, you can expect to see flight prices from Seattle to Washington, D.C. Dulles Intl Airport for around $650.

What is the cheapest time of day to depart on your flight to Washington, D.C. Dulles Intl Airport?

Flying to Washington, D.C. Dulles Intl Airport from Seattle in the afternoon is the least expensive time of day to depart. momondo users have found prices as low as $388 when looking at flights departing in the afternoon. If you have a flexible travel schedule, then try to avoid flying at noon when prices are $601 on average. Flights to Washington, D.C. Dulles Intl Airport from Seattle at noon are generally more expensive because this time of day is more convenient for travelers’ schedules.

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

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

How far in advance should I book a flight from Seattle to Washington, D.C. Dulles Intl Airport?

You are more likely to see cheaper flights to Washington, D.C. Dulles Intl Airport from Seattle when booking weeks ahead of your departure date. In general, you can expect to find flights to Washington, D.C. Dulles Intl Airport for around $456 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Washington, D.C. Dulles Intl Airport from Seattle for as low as $361 on momondo.

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

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

Can stopping save me money on Seattle to Washington, D.C. Dulles Intl Airport flights?

You could potentially save up to 22% on your flight if you consider stops on a Seattle to Washington, D.C. Dulles Intl Airport flight.

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

As of November 2026, prices for Seattle to Washington, D.C. Dulles Intl Airport flights are approximately 18% more expensive when compared to flights at the same time last year.

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

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

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

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

Best Price Found

$169

Fastest flight time

4h 50m

Direct flights

Every day
The best one-way flight to Washington, D.C. Dulles Intl Airport from Seattle in the past 72 hours is $169. The best round-trip flight deal from Seattle to Washington, D.C. Dulles Intl Airport found on momondo in the last 72 hours is $297.
The fastest flight from Seattle to Washington, D.C. Dulles Intl Airport takes 4h 50m
Direct flights go from Seattle to Washington, D.C. Dulles Intl Airport every day.

Frequently asked questions about flying from Seattle to Washington, D.C. Dulles Intl Airport

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

    There are 2299.7 mi between Seattle/Tacoma Intl and Washington, D.C. Dulles Intl. A reasonable flight in good conditions will take 4h 50m.

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

    Prices for flights from Seattle/Tacoma Intl Airport to Washington, D.C. Dulles Intl Airport are refreshed on a daily basis.

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

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

    The minimum age a child must be to fly alone is five but airlines that offer an unaccompanied minor (UNMR) service will have their own age restrictions, including rules around flight length, timings, and stopovers. We always recommend checking with the individual airline you are booking with to travel from Seattle/Tacoma Intl Airport to Washington, D.C. Dulles Intl Airport.

  • What documentation or ID do you need to fly to Washington, D.C. Dulles Intl Airport?

    The travel and health documents required for your trip to Washington, D.C. Dulles 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 Washington, D.C. Dulles 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 Seattle to Washington, D.C. Dulles Intl Airport?

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

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

Compare and see reviews for airlines that fly from Seattle to Washington, D.C. Dulles Intl Airport with momondo
Airline
Rating
Free Cancellation
Price
DeltaPriceFrom $147Free CancellationRating
7.8
8,696 reviews
Search Delta flights
American AirlinesPriceFrom $196Free CancellationRating
7.0
12,230 reviews
Search American Airlines flights
Alaska AirlinesPriceFrom $236Free CancellationRating
7.9
13,138 reviews
Search Alaska Airlines flights
United AirlinesPriceFrom $239Free CancellationRating
7.3
10,460 reviews
Search United Airlines flights
  • Alaska Airlines Flights From Seattle to Washington, D.C. Dulles Intl Airport

    Across 3 Alaska Airlines flights from Seattle to Washington, D.C. Dulles Intl Airport this week, the average price was $467, with the best Alaska Airlines deals starting from $236 round-trip. 13,136 users have rated Alaska Airlines on momondo, with an average score of 7.9/10.

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

    Delta is also a popular choice for this route. Delta flight deals for Seattle to Washington, D.C. Dulles Intl Airport start from as low as $147 round-trip, depending on your selected dates, with average Delta deals seen on momondo around $321. Delta operates 6 flights to Washington, D.C. Dulles Intl Airport from Seattle in an average week. Users have rated it 7.8/10 across 8,700 reviews.

Traveling to a place near Washington, D.C.?

Book flights to Washington, D.C. if you plan to visit one of these locations
Alexandria
National Harbor
Arlington
Gettysburg
Winchester
Fredericksburg
Waldorf
Laurel
Gaithersburg
Linthicum Heights
Woodbridge
Rockville
Silver Spring
Sterling
Towson
Fairfax
Springfield
Glen Burnie
Edgewood
Chantilly

Why use momondo?

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

momondo compares prices from hundreds of airlines and agents so you can find and book the best deal on flights from Seattle to Washington, D.C.. Millions of users trust and use momondo every year so you are in good hands.

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

Yes. All flights to Washington, D.C. from Seattle on momondo can be compared and filtered by various policies on offer, including flexible booking.

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

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 Seattle to Washington, D.C..

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

If you are not ready to book a flight from Seattle to Washington, D.C. now, use our insights above to find helpful tips or alternatively set up a price alert, where momondo will track prices on flights to Washington, D.C. and let you know when they change.

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1 adult
Thu 12/3
Thu 12/10

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