Cheap flights from Seattle to Washington, D.C. from $114

This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from Seattle to Washington, D.C. departing on 9/16. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.
1 adult
1 adult, Economy, 0 bags

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

Cheap round-trip flights

Enter your travel dates to find the best prices.
United Airlines Logo
11:00 pm - 9:28 am
SEA
-
IAD
7h 28m
1 stop
United Airlines Logo
1:20 pm - 4:06 pm
IAD
-
SEA
5h 46mnonstop
$291United Airlines
Fri, Aug 28 - Tue, Sep 1
Alaska Airlines Logo
9:35 pm - 5:40 am
SEA
-
IAD
5h 05mnonstop
Alaska Airlines Logo
7:00 am - 9:37 am
IAD
-
SEA
5h 37mnonstop
$294Alaska Airlines
Fri, Aug 28 - Sun, Aug 30
American Airlines Logo
10:00 pm - 9:30 am
SEA
-
DCA
8h 30m
1 stop
American Airlines Logo
5:18 pm - 10:57 pm
DCA
-
SEA
8h 39m
1 stop
$295American Airlines
Tue, Aug 25 - Fri, Sep 11
Alaska Airlines Logo
3:56 pm - 11:59 pm
SEA
-
IAD
5h 03mnonstop
Alaska Airlines Logo
7:00 am - 9:37 am
IAD
-
SEA
5h 37mnonstop
$295Alaska Airlines
Wed, Sep 2 - Sun, Sep 6
United Airlines Logo
6:10 pm - 5:25 am
SEA
-
IAD
8h 15m
1 stop
United Airlines Logo
6:00 pm - 8:54 pm
IAD
-
SEA
5h 54mnonstop
$296United Airlines
Fri, Aug 21 - Sun, Aug 23
Frontier Logo
7:06 pm - 12:51 pm
SEA
-
DCA
14h 45m
1 stop
Frontier Logo
1:59 pm - 9:19 am
DCA
-
SEA
22h 20m
1 stop
$297Frontier
Thu, Aug 13 - Wed, Aug 19
Frontier Logo
7:06 pm - 12:51 pm
SEA
-
DCA
14h 45m
1 stop
Frontier Logo
1:59 pm - 1:17 pm
DCA
-
SEA
26h 18m
1 stop
$298Frontier
Tue, Aug 4 - Sat, Aug 8
Delta Logo
7:20 am - 3:21 pm
SEA
-
DCA
5h 01mnonstop
Delta Logo
4:35 pm - 7:41 pm
DCA
-
SEA
6h 06mnonstop
$304Delta
Thu, Aug 13 - Wed, Aug 19
Delta Logo
7:20 am - 3:21 pm
SEA
-
DCA
5h 01mnonstop
Delta Logo
4:35 pm - 7:41 pm
DCA
-
SEA
6h 06mnonstop
$305Delta
Thu, Aug 13 - Wed, Aug 19
American Airlines Logo
7:51 am - 7:26 pm
SEA
-
BWI
8h 35m
1 stop
American Airlines Logo
6:16 pm - 12:11 am
BWI
-
SEA
8h 55m
1 stop
$333American Airlines
Thu, Sep 10 - Mon, Sep 14

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Alaska Airlines flights from Seattle to Washington, D.C.

Our best Alaska Airlines deals on Seattle to Washington, D.C. flight tickets
Alaska Airlines
Aug 28
SEA9:35 pmSeattle/Tacoma Intl
5h 05m
IAD5:40 amWashington, D.C. Dulles Intl
Aug 30
IAD7:00 amWashington, D.C. Dulles Intl
5h 37m
SEA9:37 amSeattle/Tacoma Intl
$294
Alaska Airlines
Sep 2
SEA3:56 pmSeattle/Tacoma Intl
5h 03m
IAD11:59 pmWashington, D.C. Dulles Intl
Sep 6
IAD7:00 amWashington, D.C. Dulles Intl
5h 37m
SEA9:37 amSeattle/Tacoma Intl
$295
Alaska Airlines
Sep 14
SEA9:35 pmSeattle/Tacoma Intl
5h 05m
IAD5:40 amWashington, D.C. Dulles Intl
Sep 21
IAD7:00 amWashington, D.C. Dulles Intl
5h 37m
SEA9:37 amSeattle/Tacoma Intl
$298

United Airlines flights from Seattle to Washington, D.C.

Our best United Airlines deals on Seattle to Washington, D.C. flight tickets
United Airlines
Aug 28
SEA11:00 pmSeattle/Tacoma Intl
7h 28m
1 stop
IAD9:28 amWashington, D.C. Dulles Intl
Sep 1
IAD1:20 pmWashington, D.C. Dulles Intl
5h 46m
SEA4:06 pmSeattle/Tacoma Intl
$291
United Airlines
Aug 21
SEA6:10 pmSeattle/Tacoma Intl
8h 15m
1 stop
IAD5:25 amWashington, D.C. Dulles Intl
Aug 23
IAD6:00 pmWashington, D.C. Dulles Intl
5h 54m
SEA8:54 pmSeattle/Tacoma Intl
$296
United Airlines
Aug 28
SEA11:00 pmSeattle/Tacoma Intl
7h 28m
1 stop
IAD9:28 amWashington, D.C. Dulles Intl
Aug 30
IAD6:30 amWashington, D.C. Dulles Intl
8h 14m
1 stop
SEA11:44 amSeattle/Tacoma Intl
$297

momondo Fare Finder

 
Customize your flight search to find flights from Seattle to Washington, D.C. that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, momondo users made 832,500 searches. Data last updated June 26, 2026.
Use the filters below to find and compare flights from Seattle to Washington, D.C. that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

SeattleWashington, D.C.

SEA - IAD

SEAIAD

Seattle/Tacoma Intl

Fri 8/28

11:00 pm-9:28 am

1 stop7h 28m

Washington, D.C. Dulles Intl

Tue 9/1

1:20 pm-4:06 pm

Nonstop5h 46m

$291

SeattleWashington, D.C.

SEA - IAD

SEAIAD

Seattle/Tacoma Intl

Fri 8/28

9:35 pm-5:40 am

Nonstop5h 05m

Washington, D.C. Dulles Intl

Sun 8/30

7:00 am-9:37 am

Nonstop5h 37m

$294

SeattleWashington, D.C.

SEA - DCA

SEADCA

Seattle/Tacoma Intl

Tue 8/25

10:00 pm-9:30 am

1 stop8h 30m

Washington, D.C. Reagan-National

Fri 9/11

5:18 pm-10:57 pm

1 stop8h 39m

$295
Quickest round-trip

SeattleWashington, D.C.

SEA - IAD

SEAIAD

Seattle/Tacoma Intl

Wed 9/2

3:56 pm-11:59 pm

Nonstop5h 03m

Washington, D.C. Dulles Intl

Sun 9/6

7:00 am-9:37 am

Nonstop5h 37m

$295

SeattleWashington, D.C.

SEA - IAD

SEAIAD

Seattle/Tacoma Intl

Fri 8/21

6:10 pm-5:25 am

1 stop8h 15m

Washington, D.C. Dulles Intl

Sun 8/23

6:00 pm-8:54 pm

Nonstop5h 54m

$296

SeattleWashington, D.C.

SEA - DCA

SEADCA

Seattle/Tacoma Intl

Thu 8/13

7:06 pm-12:51 pm

1 stop14h 45m

Washington, D.C. Reagan-National

Wed 8/19

1:59 pm-9:19 am

1 stop22h 20m

$297

SeattleWashington, D.C.

SEA - DCA

SEADCA

Seattle/Tacoma Intl

Tue 8/4

7:06 pm-12:51 pm

1 stop14h 45m

Washington, D.C. Reagan-National

Sat 8/8

1:59 pm-1:17 pm

1 stop26h 18m

$298

SeattleWashington, D.C.

SEA - DCA

SEADCA

Seattle/Tacoma Intl

Thu 8/13

7:20 am-3:21 pm

Nonstop5h 01m

Washington, D.C. Reagan-National

Wed 8/19

4:35 pm-7:41 pm

Nonstop6h 06m

$304

SeattleWashington, D.C.

SEA - DCA

SEADCA

Seattle/Tacoma Intl

Thu 8/13

7:20 am-3:21 pm

Nonstop5h 01m

Washington, D.C. Reagan-National

Wed 8/19

4:35 pm-7:41 pm

Nonstop6h 06m

$305

SeattleBaltimore

SEA - BWI

SEABWI

Seattle/Tacoma Intl

Thu 9/10

7:51 am-7:26 pm

1 stop8h 35m

Baltimore/Washington

Mon 9/14

6:16 pm-12:11 am

1 stop8h 55m

$333

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.

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.?

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

The month of January is, on average, the cheapest month to fly to Washington, D.C. from Seattle, with most prices found around $99. If you’re not able to fly to Washington, D.C. in January, then July is your next best option. Flight prices from Seattle to Washington, D.C. during July average around $113.

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

On average, the least expensive day to fly to Washington, D.C. from Seattle is on a Wednesday. momondo users have found tickets for Wednesday departures for as low as $423. However, this price may fluctuate depending on the airline, the season, and holidays. When flying out on a Sunday, the most expensive travel day of the week, you can expect to see flight prices from Seattle to Washington, D.C. for around $604.

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

In the afternoon is the cheapest time of day to fly from Seattle to Washington, D.C. when you can find flight prices for as low as $352. Flying to Washington, D.C. in the afternoon is an ideal time because this is during off-peak travel hours. Try not to purchase tickets in the morning because they tend to be around $499. Of course, these prices can vary depending on the time of year and what airport you fly to.

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

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

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

You are more likely to see cheaper flights to Washington, D.C. from Seattle when booking weeks ahead of your departure date. In general, you can expect to find flights to Washington, D.C. for around $433 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Washington, D.C. from Seattle for as low as $354 on momondo.

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

There are 4 cabin classes available to choose from on Seattle to Washington, D.C. 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. flights?

No. A direct flight is the cheapest option for a flight between Seattle to Washington, D.C..

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

As of June 2026, prices for Seattle to Washington, D.C. flights are approximately 22% cheaper when compared to flights at the same time last year.

When to book flights from Seattle to Washington, D.C.

Are you open to changing your travel dates? Check out the ideal times to fly from Seattle to Washington, D.C. 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. (SEA to WAS) flight deals and tips

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

Best Price Found

$230

Fastest flight time

4h 53m

Direct flights

Mon, Tue, Wed, Thu, Fri and Sat

Airports in Washington, D.C.

2 airports
The best one-way flight to Washington, D.C. from Seattle in the past 72 hours is $230. The best round-trip flight deal from Seattle to Washington, D.C. found on momondo in the last 72 hours is $341.
The fastest flight from Seattle to Washington, D.C. takes 4h 53m
Direct flights go from Seattle to Washington, D.C. on Monday, Tuesday, Wednesday, Thursday, Friday and Saturday. There are no airlines offering direct flights.
There are 2 airports in Washington, D.C.. From Seattle there are direct flights to Washington, D.C. Reagan-National (DCA), Baltimore/Washington (BWI), Washington, D.C. Dulles Intl (IAD).

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

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

    There are 2320.5 mi between Seattle/Tacoma Intl and Washington, D.C.. 4h 53m is a normal flight duration for this route.

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

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

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

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

    The minimum age for a child to fly alone is five, but airlines offering an unaccompanied minor (UNMR) service may have their age restrictions, such as regulations concerning flight duration, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from Seattle/Tacoma Intl Airport to Washington, D.C..

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

    The travel and health documents you'll need for your trip to Washington, D.C. may differ based on your itinerary and personal situation. Typically, you should have several documents on hand, such as a national ID card or driver's license and a passport that is valid for six months after your intended arrival at Washington, D.C.. It is always advisable to seek advice from your airline or a trusted third party, such as IATA.

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

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

Best airlines flying from Seattle to Washington, D.C.

Compare and see reviews for airlines that fly from Seattle to Washington, D.C. with momondo
Airline
Rating
Free Cancellation
Price
DeltaPriceFrom $103Free CancellationRating
7.8
8,453 reviews
Search Delta flights
FrontierPriceFrom $126Free CancellationRating
5.6
2,864 reviews
Search Frontier flights
Hawaiian AirlinesPriceFrom $128Free CancellationRating
7.8
2,826 reviews
Search Hawaiian Airlines flights
American AirlinesPriceFrom $178Free CancellationRating
7.1
11,768 reviews
Search American Airlines flights
Alaska AirlinesPriceFrom $199Free CancellationRating
7.9
12,579 reviews
Search Alaska Airlines flights
SouthwestPriceFrom $199Free CancellationRating
7.9
4,245 reviews
Search Southwest flights
United AirlinesPriceFrom $219Free CancellationRating
7.4
9,893 reviews
Search United Airlines flights
  • Alaska Airlines Flights From Seattle to Washington, D.C.

    Alaska Airlines is one of the most popular airlines flying from Seattle to Washington, D.C., operating 26 flights/week on average for this route. A good Alaska Airlines flight deal for Seattle to Washington, D.C. starts from $199 round-trip, up to an average price of $465. Our users have rated Alaska Airlines at 7.9/10.

  • Delta Flights From Seattle to Washington, D.C.

    Delta (7.8/10 from 8,453 reviews) operates around 14 flights from Seattle to Washington, D.C. in any given week. The average Delta airfare for this route is around $345, with deals from around $103 rare but found on momondo. Referenced prices are for round-trip Seattle to Washington, D.C. flight searches in the last 72 hours.

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
Waldorf
Laurel
Woodbridge
Fredericksburg
Gaithersburg
Colonial Beach
Linthicum Heights
Rockville
Silver Spring
Towson
Manassas
Tysons
Springfield
Fairfax
Bethesda
Glen Burnie

Why use momondo?

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

To find the flight that best suits your needs, momondo gathers a range of flights from a large pool of different airlines and agents; you can then use our insights and filters to find and book the right flight to Washington, D.C. from Seattle.

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

Flights from Seattle to Washington, D.C. with flexible booking policies can be found by using the search form above and then selecting our dedicated flexible booking filter, which will highlight only the flights where this policy is applied.

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

Once you have performed a search for Seattle to Washington, D.C. flights, momondo helps you find the right one by offering useful filters to narrow down your flight selection. Flights can be filtered by multiple factors such as airline, airport and price; but also by other criteria like aircraft type and payment method.

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

Price alerts on flights to Washington, D.C. from Seattle 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.

An easier way to manage your Washington, D.C. trip

We make it super easy to schedule, organize and travel with friends or family. Trips is free — and available to use no matter where you book.

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1 adult
Sun 7/26
Sun 8/2

Find better results for your trip to the United States

Fly into one of these airports located in Washington, D.C.

Airports listed have a maximum distance of 22.4 mi from Washington, D.C.