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SEA - IAD

Find cheap flights from Seattle to Washington Dulles Airport from C$ 190

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from Seattle to Washington, D.C. departing on 4/6. Fares are subject to change and may not be available on all flights or dates of travel. Click the price to replicate the search for this deal.
1 adult
0 bags
Tue 4/6
Tue 11/6

Search hundreds of travel sites at once for deals on flights to Washington Dulles Airport

 
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Seattle to Washington, D.C., as well as popular online travel agencies
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Seattle to Washington, D.C., as well as popular online travel agencies
In the last 7 days, travellers have searched 42,830,901 times on KAYAK, and here is why:

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Cheap flight deals from Seattle to Washington, D.C. (SEA-IAD)

Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from Seattle to Washington, D.C. that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.
Discover the best prices and deals for you by selecting your travel dates.
Choose your dates
8:35 a.m. - 4:45 p.m.SEA-IAD
5h 10mdirect
7:30 a.m. - 10:14 a.m.IAD-SEA
5h 44mdirect
C$ 379Delta
Find Deal
Wed, 5 Jun - Tue, 11 Jun
10:22 p.m. - 6:25 a.m.SEA-IAD
5h 03mdirect
7:31 a.m. - 10:20 a.m.IAD-SEA
5h 49mdirect
C$ 387Delta
Find Deal
Fri, 31 May - Tue, 4 Jun
9:55 p.m. - 5:58 a.m.SEA-IAD
5h 03mdirect
7:30 a.m. - 10:12 a.m.IAD-SEA
5h 42mdirect
C$ 395Delta
Find Deal
Wed, 3 Jul - Sun, 7 Jul
5:40 p.m. - 8:47 p.m.SEA-IAD
24h 07m1 stop
5:25 p.m. - 10:40 a.m.IAD-SEA
20h 15m1 stop
C$ 404Sun Country Air
Find Deal
Fri, 31 May - Mon, 3 Jun
11:28 p.m. - 7:40 a.m.SEA-IAD
5h 12mdirect
4:19 p.m. - 10:59 p.m.IAD-SEA
9h 40m1 stop
C$ 406Alaska Airlines
Find Deal
Wed, 29 May - Fri, 31 May
6:00 a.m. - 5:54 p.m.SEA-IAD
8h 54m1 stop
7:00 a.m. - 9:30 a.m.IAD-SEA
5h 30mdirect
C$ 415Alaska Airlines
Find Deal
Fri, 31 May - Mon, 3 Jun
5:40 p.m. - 8:22 p.m.SEA-IAD
23h 42m1 stop
12:30 p.m. - 7:55 a.m.IAD-SEA
22h 25m1 stop
C$ 431Sun Country Air
Find Deal
Fri, 24 May - Sun, 26 May
12:25 a.m. - 9:55 a.m.SEA-IAD
6h 30m1 stop
5:23 p.m. - 8:10 p.m.IAD-SEA
5h 47mdirect
C$ 536United Airlines
Find Deal
Thu, 30 May - Tue, 4 Jun
12:30 a.m. - 11:52 a.m.SEA-IAD
8h 22m1 stop
10:10 p.m. - 12:54 a.m.IAD-SEA
5h 44mdirect
C$ 545United Airlines
Find Deal
Mon, 1 Jul - Tue, 16 Jul
9:35 a.m. - 11:20 a.m.SEA-IAD
22h 45m3 stops
8:25 a.m. - 8:45 a.m.IAD-SEA
27h 20m3 stops
C$ 627
Find Deal
Fri, 24 May - Mon, 27 May

Flights from Seattle to Washington, D.C. - Travel Insights & Trends

Get data-powered insights and trends into flights from Seattle to Washington, D.C. to help you find the cheapest flights, the best time to fly and much more.

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

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for flights from Seattle to Washington, D.C. Dulles Intl Airport, removes the top 0.1% to account for outliers, and then takes the median of all values for each month.
The cheapest month for flights from Seattle to Washington, D.C. Dulles Intl Airport is February, where tickets cost C$ 326 on average. On the other hand, the most expensive months are June and May, where the average cost of tickets is C$ 754 and C$ 736 respectively.

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

To calculate daily average prices, KAYAK takes all prices for each day before departure over the last year for flights from Seattle to Washington, D.C. Dulles Intl Airport, removes the top 0.1% to account for outliers, and then takes the average of all the values for each month.
To get a below average price on the flight from Seattle to Washington, D.C. Dulles Intl Airport, you should book around 2 weeks before departure. For the absolute cheapest price, our data suggests you should book 25 days before departure.

Which airlines provide the cheapest flights from Seattle to Washington Dulles Airport?

The cheapest price for the route for each airline clicked by KAYAK users in the last 72 hours.
In the last 72 hours, the cheapest one-way ticket from Seattle to Washington Dulles Airport found on KAYAK was with Alaska Airlines for C$ 190. Delta proposed a round-trip connection from C$ 379 and Sun Country Air from C$ 404.

Which airlines fly most frequently between Seattle and Washington Dulles Airport?

United Airlines (5 flights per day), Alaska Airlines (4 flights per day), and Delta (2 flights per day) are the most frequent flyers of this route.

Which airlines fly direct between Seattle and Washington, D.C. Dulles Intl Airport?

Airline and price data is aggregated from results in KAYAK’s search results from the last 2 weeks for flights from Seattle to Washington, D.C. Dulles Intl Airport.
There are 3 airlines that fly direct from Seattle to Washington, D.C. Dulles Intl Airport. They are: Alaska Airlines, Delta and United Airlines. The cheapest price of all airlines flying this route was found with Alaska Airlines at C$ 367. On average, the best prices for this route can be found at Alaska Airlines.

How many flights are there between Seattle and Washington, D.C. Dulles Intl Airport per day?

Each day, there are between 10 and 13 nonstop flights that take off from Seattle and land in Washington, D.C. Dulles Intl Airport, with an average flight time of 5h 03m. The most common departure time is 11:00 p.m. and most flights take off in the morning. Each week, there are 81 flights. The most frequent day of departure is Monday, when 16% of all weekly flights depart. The fewest flights depart on a Saturday.

Which cabin class options are there for flights between Seattle and Washington, D.C. Dulles Intl Airport?

The average price of flights for each cabin class for the route found by users searching on KAYAK over the last 2 weeks.
There are 2 cabin class options for the route. These are Business and Economy. Perform a search on KAYAK to find the latest prices and availability for all cabin fares, which differ across airlines.

How long does a flight from Seattle to Washington Dulles Airport take?

The duration of a direct flight to Washington Dulles Airport from Seattle is typically 4h 52m. The journey crosses a distance of 5,953 km.

What’s the earliest departure time from Seattle to Washington Dulles Airport?

Early birds can take the earliest flight from Seattle at 7:35 am and will be landing in Washington, D.C. Dulles Intl Airport at 3:40 pm.

What’s the latest departure time from Seattle to Washington Dulles Airport?

If you prefer to fly at night, the latest flight from Seattle to Washington, D.C. Dulles Intl Airport jets off at 11:29 pm and lands at 7:28 am.

Good to know

Low season

January

High season

July

Cheapest flight

C$ 190
Best time to beat the crowds (35% less expensive on average)
Most popular time to fly (20% more expensive on average)
Flight from Seattle to Washington Dulles Airport

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

Are your dates flexible? Find out the best times to travel from Seattle to Washington, D.C. based on our flight data from the last year. Discover the cheapest month and even day to fly.
Estimated round-trip price
KAYAK looks at all historical flight data for each date to provide a predicted price for one-way trips or round-trips with a duration up to 40 days. While we try to provide actual minimum prices for each date, some prices are predictions and actual prices may differ.

FAQs for booking Seattle to Washington Dulles Airport flights

  • Is there a lounge at Seattle-Tacoma International Airport?

    If you want a quiet place where you can relax while you wait for your flight from Seattle to Washington, DC, you can head to the Club at SEA. There are two locations in Concourse A. The one by Gate A12 is open from around 5 am to midnight. The second is above Gate S10 on the mezzanine floor and is open from about 6 am to 7 pm. For about $45, you can enjoy snacks and beverages, including bar service, as well as television and magazines.

  • Will there be inflight entertainment on my trip from Seattle to Washington?

    Many airlines offering flights to Washington Dulles Airport from Seattle provide inflight entertainment. You can check which ones do by expanding the aircraft details in your KAYAK search results. For example, United Airlines has both personal seatback systems as well as streaming options for passengers to enjoy movies, music, and shows.

  • Are there pet relief areas at the airports in Seattle and Washington, DC?

    If you are traveling with your pet or service animal, both airports have pet relief stations with waste disposal bags and trash receptacles. In SEA, there are several pet relief areas throughout the airport, including in the main terminal and in Concourses D, S, and N. In IAD, you can find them by Gates D1 and A32, as well as by the parking lot across from the exit by Baggage Claim 1.

  • Can I rent a car at IAD?

    Many of the major car rental companies offer services at IAD, including Avis, Enterprise, and SIXT. You can catch a shuttle to locations outside Doors 2 and 4 from baggage claim at Curbs 2C or 2D.

  • What is the cheapest flight from Seattle to Washington, D.C. Dulles Intl Airport?

    In the last 3 days, the lowest price for a flight from Seattle to Washington, D.C. Dulles Intl Airport was C$ 139 for a one-way ticket and C$ 277 for a round-trip.

  • Which airlines offer Wi-Fi service onboard planes from Seattle to Washington Dulles Airport?

    All the following airlines offer inflight Wi-Fi service on the Seattle to Washington Dulles Airport flight route: Alaska Airlines, American Airlines, JetBlue, Delta, United Airlines, Lufthansa, and Aeromexico.

  • Which aircraft models fly most regularly from Seattle to Washington Dulles Airport?

    The Boeing 737 MAX 9 is the aircraft model that flies most regularly on the Seattle to Washington Dulles Airport flight route.

  • Which airline alliances offer flights from Seattle to Washington Dulles Airport?

    oneworld, Star Alliance, and SkyTeam are the airline alliances operating flights between Seattle and Washington Dulles Airport, with Star Alliance being the most commonly used for this route.

  • On which days can I fly direct from Seattle to Washington Dulles Airport?

    There are direct flights from Seattle to Washington Dulles Airport on a daily basis.

  • How does KAYAK find such low prices on flights from Seattle to Washington Dulles Airport?

    KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from Seattle to Washington Dulles Airport.

  • How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Seattle to Washington Dulles Airport?

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to Washington Dulles Airport from Seattle is likely to change within 7 days, so travellers know whether to wait or book now.

  • What is the Hacker Fare option on flights from Seattle to Washington Dulles Airport?

    Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly to Washington Dulles Airport with an airline and back to Seattle with another airline.

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Seattle to Washington Dulles Airport?

    Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying to Washington Dulles Airport from Seattle up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

See more FAQs

Top tips for finding a cheap flight from Seattle to Washington, D.C.

  • Looking for a cheap flight? 25% of our users found flights on this route for C$ 932 or less round-trip.
  • Seattle-Tacoma International Airport (SEA), also called Sea-Tac, is the main airport for the greater Seattle metropolis. It is about 14 miles from downtown Seattle, and Alaska and Delta Airlines use it as a hub. Washington Dulles International Airport (IAD) is the main airport for the Washington DC area, where it is a United Airlines hub, and is located about 42 miles from downtown DC.
  • You could take one of the many non-stop flights from Seattle to Washington Dulles Airport, or you may prefer a flight with one or more stops. For example, Delta flies to IAD with stops in Detroit or New York City, and American Airlines can take you to DC via Chicago and Charlotte.
  • Flights from Washington Dulles Airport to Seattle average about 2,087 lbs. in CO2 emissions per passenger. If you would like to keep that number as low as possible, you could fly Alaska Air’s non-stop service, which ranges from only around 1,216 to 1,461 lbs. in emissions, about 42% to 30% less than the average.
  • You have two public transport options from downtown Seattle to the airport. The Link Light Rail costs about $3 a person, and you can get tickets at the station. The King County Metro Bus also has numerous routes from the city center to the airport for around $3 as well. You can pay the driver in cash, but you need exact change.
  • If you choose to drive and park your car at SEA, there are long-term parking lots at the airport. At the Terminal Direct parking on the 4th floor of the garage, you can walk to the main terminal from this floor for about $42 a day or around $294 a week. You can park on the other floors for around $34 a day or $169 per week.
See more tips

Prefer to fly non-stop from Seattle to Washington Dulles Airport?

Find which airlines fly direct from Seattle/Tacoma Intl to Dulles Intl, which days they fly and book direct flights.

Nonstop departures

Seattle/Tacoma Intl to Washington, D.C. Dulles Intl

Monday

ANA, Air Tahiti Nui, Alaska Airlines, +13 more

ANA, Air Tahiti Nui, +14 more

Tuesday

ANA, Air Tahiti Nui, Alaska Airlines, +15 more

ANA, Air Tahiti Nui, +16 more

Wednesday

ANA, Air Tahiti Nui, Alaska Airlines, +13 more

ANA, Air Tahiti Nui, +14 more

Thursday

ANA, Air Tahiti Nui, Alaska Airlines, +15 more

ANA, Air Tahiti Nui, +16 more

Friday

ANA, Air Tahiti Nui, Alaska Airlines, +14 more

ANA, Air Tahiti Nui, +15 more

Saturday

ANA, Air Tahiti Nui, Alaska Airlines, +15 more

ANA, Air Tahiti Nui, +16 more

Sunday

ANA, Air Tahiti Nui, Alaska Airlines, +14 more

ANA, Air Tahiti Nui, +15 more

See more nonstop flights

Nonstop returns

Washington, D.C. Dulles Intl to Seattle/Tacoma Intl

Monday

Air Tahiti Nui, Alaska Airlines, Austrian Airlines, +12 more

Air Tahiti Nui, Alaska Airlines, +13 more

Tuesday

Air Tahiti Nui, Alaska Airlines, Austrian Airlines, +13 more

Air Tahiti Nui, Alaska Airlines, +14 more

Wednesday

Air Tahiti Nui, Alaska Airlines, Austrian Airlines, +12 more

Air Tahiti Nui, Alaska Airlines, +13 more

Thursday

Air Tahiti Nui, Alaska Airlines, Austrian Airlines, +13 more

Air Tahiti Nui, Alaska Airlines, +14 more

Friday

Air Tahiti Nui, Alaska Airlines, Austrian Airlines, +12 more

Air Tahiti Nui, Alaska Airlines, +13 more

Saturday

Air Tahiti Nui, Alaska Airlines, Austrian Airlines, +13 more

Air Tahiti Nui, Alaska Airlines, +14 more

Sunday

Air Tahiti Nui, Alaska Airlines, Austrian Airlines, +12 more

Air Tahiti Nui, Alaska Airlines, +13 more

See more nonstop flights
See more nonstop flights

Top airline flying from Seattle to Washington, D.C.

 
See real verified KAYAK customer reviews for airlines flying from Seattle to Washington, D.C.. Airline scores are aggregated from all reviews left by passengers on KAYAK after flying with an airline. KAYAK doesn’t show reviews that are older than 5 years. Learn how KAYAK collects reviews.
Need help choosing which airline to fly with from Seattle to Washington, D.C.? KAYAK airline reviews give an overall score for each airline based on loads of factors, including comfort, boarding, in-flight entertainment and more, to make your decision easier. See airline scores according to verified KAYAK customer reviews.
8.0
Alaska AirlinesOverall score based on 9134 reviews
8.6Crew
7.3Food
7.3Entertainment
8.2Boarding
7.9Comfort
Airline reviews

The flight was delayed because the pilots had not arrived on their previous flight yet. The flight was 100% full so it was pretty crowded. I miss having the screens on the back of the seats. It would be great if the Alaska planes had the clip so you can put your phone or tablet on the back of the seat in front of you to not strain your neck. Everything else was very smooth.

10.0 ExcellentAnonymous, May 2024SEA - BOS
Read more about Alaska Airlines reviews

The flight was delayed because the pilots had not arrived on their previous flight yet. The flight was 100% full so it was pretty crowded. I miss having the screens on the back of the seats. It would be great if the Alaska planes had the clip so you can put your phone or tablet on the back of the seat in front of you to not strain your neck. Everything else was very smooth.

It was fine since it ensure we went to our destination in time.

I bought the cheapest ticket. No meal, no checked luggage so I didn't expect much and was surprised by how good the flight and service was. Alaska is now my favorite airline.

No entertainment, food was cookies & juice,water, soda or coffee.

My baggage was in another flight, anit was delayed for one hour.

The maintenance delay was seemingly handled very poorly... Little to no information was provided to the passengers sitting on board for an extended period of time. On a brighter note, at least the cabin crew (flight attendants) did the best they could. They seemingly were provided very little information with regards to the delay. Unless absolutely beyond my control, I can’t imagine buying a ticket on Alaska airlines again, based on this and a previous experience my wife recently had, along with complaints overheard from other passengers.

The only issue was in the wheelchair waiting area before we got on the plane. They seemed very disorganized. Everyone we encountered after that was great! We loved Cassandra at check-in. She was awesome. The flight attendants were wonderful too! The lady helping with the waiting wheelchair when we got off the plane was awesome too!

Expect to get miles for us having to miss our first planned flight due to them waiting on passengers that decided to be late to the airport.

Up on arrival, due to twisted ankle, I wasn’t able to walk. Requested for a wheelchair. They immediately asked for it. After 10 minutes wait a young man named Carlos picked me up at the gate, got my baggage and took me to the pick up area. It was a great service. Thanks Alaska Air line

Once I was in my seat, it wasn't as comfortable. It was very tight (width wise).

Book cheap flights from Seattle to Washington, D.C.

Recent one-way flight deals

 
Only flying one-way? Below are some of the best one-way flight deals from Seattle to Washington, D.C. found on KAYAK in the last 72 hours.
4/6Tue
directAlaska Airlines
4h 59mSEA-IAD
C$ 190
4/6Tue
directDelta
5h 10mSEA-IAD
C$ 192
3/6Mon
directDelta
5h 04mSEA-IAD
C$ 198
31/5Fri
directAlaska Airlines
5h 08mSEA-IAD
C$ 200
16/9Mon
directDelta
4h 56mSEA-IAD
C$ 205
10/7Wed
1 stopSun Country Air
8h 18mSEA-IAD
C$ 216
4/6Tue
1 stopSun Country Air
19h 36mSEA-IAD
C$ 223
17/6Mon
1 stopSun Country Air
13h 55mSEA-IAD
C$ 237
26/6Wed
directUnited Airlines
4h 59mSEA-IAD
C$ 267
19/8Mon
1 stopUnited Airlines
8h 51mSEA-IAD
C$ 279

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Last minute flights from Seattle to Washington, D.C.

Last minute flight, train and bus deals

 
These last-minute flight deals are the cheapest flights found on KAYAK in the last 72 hours for flights from Seattle to Washington, D.C. that are departing in the next 10 days.
8/5Wed
multi-stopSun Country Air
15h 42mSEA-IAD
16/5Thu
multi-stopSun Country Air
8h 15mIAD-SEA
C$ 855
10/5Fri
directAlaska Airlines
5h 05mSEA-IAD
12/5Sun
directAlaska Airlines
5h 51mIAD-SEA
C$ 874
10/5Fri
directDelta
5h 09mSEA-IAD
12/5Sun
multi-stopDelta
7h 22mIAD-SEA
C$ 887
10/5Fri
multi-stopDelta
8h 14mSEA-IAD
14/5Tue
multi-stopDelta
7h 24mIAD-SEA
C$ 900
10/5Fri
directAlaska Airlines
4h 56mSEA-IAD
14/6Fri
directAlaska Airlines
5h 42mIAD-SEA
C$ 920
10/5Fri
directAlaska Airlines
5h 04mSEA-IAD
14/6Fri
multi-stopAlaska Airlines
19h 49mIAD-SEA
C$ 922
10/5Fri
directDelta
5h 03mSEA-IAD
13/5Mon
directDelta
5h 46mIAD-SEA
C$ 941
6/5Mon
directDelta
4h 55mSEA-IAD
12/5Sun
directDelta
5h 45mIAD-SEA
C$ 948
10/5Fri
multi-stopUnited Airlines
17h 51mSEA-IAD
14/5Tue
directUnited Airlines
5h 48mIAD-SEA
C$ 959
10/5Fri
multi-stopUnited Airlines
16h 17mSEA-IAD
20/5Mon
directUnited Airlines
5h 48mIAD-SEA
C$ 2,039

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Seattle - Washington Dulles Airport Flights

Departure:

Seattle (SEA)United States

Destination:

Washington Dulles Airport (IAD)United States

Cabin classes:

C$ 1,530
C$ 2,610
C$ 464

Browse origins:

  • Flights » 
  • Seattle

Browse destinations:

  • Flights » 
  • Worldwide » 
  • Washington, D.C. » 
  • Washington Dulles Airport