How long does a flight from Washington, D.C. to Seattle take?

Direct flights take on average 5h 46m to travel the 2,299 miles between Washington, D.C. and Seattle.

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

Each day, there are between 5 and 6 direct flights that take off from Washington, D.C. Dulles Intl Airport and land in Seattle, with an average flight time of 5h 48m. The most common departure time is 17:00 and most flights take off in the morning. Each week, there are 39 flights. The most frequent day of departure is Monday, when 15% of all weekly flights depart. The fewest flights depart on a Tuesday.

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

In the last 5 days, the lowest price for a flight from Washington, D.C. Dulles Intl Airport to Seattle was £154 for a one-way ticket and £262 for a return.

Which airlines fly most frequently between Washington, D.C. and Seattle?

Washington, D.C. and Seattle are connected by different airlines. The airlines that fly that route the most regularly are Alaska Airlines (18 flights per week), United Airlines (14 flights per week), and Delta (7 flights per week).

Which airports will I be using when flying from Washington, D.C. to Seattle?

On your way to Seattle, you’ll fly out from Washington, D.C. Dulles Intl. You’ll be landing at Seattle/Tacoma Intl.

What’s the earliest departure time from Washington, D.C. to Seattle?

Early birds can take the earliest flight from Washington, D.C. Dulles Intl Airport at 07:00 and will be landing in Seattle at 10:05.

What’s the latest departure time from Washington, D.C. to Seattle?

If you prefer to fly at night, the latest flight from Washington, D.C. Dulles Intl Airport to Seattle jets off at 17:50 and lands at 20:56.

Which airlines offer Wi-Fi service onboard planes from Washington, D.C. to Seattle?

Alaska Airlines, Delta, JetBlue, and American Airlines offer inflight Wi-Fi service on the Washington, D.C. to Seattle flight route.

Which aircraft models fly most regularly from Washington, D.C. to Seattle?

The Boeing 737 is the aircraft model that flies most regularly on the Washington, D.C. to Seattle flight route.

On which days can I fly direct from Washington, D.C. to Seattle?

There are direct flights from Washington, D.C. to Seattle on a daily basis.

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

The cheapest month for flights from Washington, D.C. Dulles Intl Airport to Seattle is January , where tickets cost £171 (return) on average. On the other hand, the most expensive months are June and July, where the average cost of round-trip tickets is £408 and £387 respectively.

How does KAYAK find such low prices on flights from Washington, D.C. to Seattle?

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 Washington, D.C. to Seattle.

How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Washington, D.C. to Seattle?

KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to Seattle from Washington, D.C. 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 Washington, D.C. to Seattle?

Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional return ticket. You could then fly to Seattle with an airline and back to Washington, D.C. with another airline.

What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Washington, D.C. to Seattle?

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 Seattle from Washington, D.C. up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

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

There is only one cabin class option available for the route, which is Economy . Perform a search on KAYAK to find the latest prices and availability for all cabin fares, which differ across airlines.

Which airlines provide the cheapest flights from Washington, D.C. to Seattle?

In the past 5 days, the cheapest return tickets from Washington, D.C. to Seattle were found on Alaska Airlines (£262) and Frontier (£265).

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

To get a below average price on the flight from Washington, D.C. Dulles Intl Airport to Seattle, you should book around 4 weeks before departure , which saves you about 59% compared to booking last minute. For the absolute cheapest price, our data suggests you should book 4 weeks before departure.

How much is a return flight from Washington, D.C. Dulles Intl Airport to Seattle?

Flight prices are below average for this route right now. Flights to Seattle from Washington, D.C. Dulles Intl Airport usually cost between £282 and £502 in November. The lowest price found in the past 5 days was £262 on Alaska Airlines (3 Nov–3 Nov).

£154 CHEAP FLIGHTS from Washington, D.C. to Seattle (IAD - SEA)

Save 25% or more on flights. Compare deals from all over the web.

Never overpay with our price tracking tools.

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Cheapest return fare

£262

Typical prices: £222-£416

Alaska Airlines

Tue 3/11Tue 3/11

IAD - SEA • Direct

Cheapest direct flights

£267

Typical prices: £198-£405

Alaska Airlines

Mon 16/11Mon 23/11

IAD - SEA • Direct

Advice from real travellers

AI-powered summary based on content written by KAYAK users. AI can make mistakes.

On Alaska, a seat upgrade may be worth paying for on this long flight.

Arrive early at Dulles or Seattle, especially during holidays and busy periods.

User tips

Direct flights

Every day

You can fly direct with Alaska Airlines, Delta, and United Airlines. Average duration is 5h 48m

Direct flights

When to book

4 weeks

in advance

Our data shows that travellers who book at least 4 weeks in advance save around 59% compared to booking last minute.

Insights

When to travel

January

Cheapest • 44% price drop

July

Most popular

Good to know

Start a new search

KAYAK searches hundreds of sites at once to find you the best travel deals.

We hope you love your trip to Seattle!

Flight Deals

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

Discover the best prices for you by selecting your travel dates on KAYAK.

Return

One-way

Last minute

Direct

Recent return flight deals from Washington, D.C. to Seattle

Tue, 3 Nov - Tue, 3 Nov

07:46 - 10:36IAD Washington, D.C. Dulles Intl-SEA Seattle/Tacoma Intl

5h 50mdirect

13:03 - 17:40SEA Seattle/Tacoma Intl-IAD Washington, D.C. Dulles Intl

25h 37m1 stop San Diego

£262Alaska Airlines

Fri, 30 Oct - Thu, 5 Nov

21:06 - 15:12IAD Washington, D.C. Dulles Intl-SEA Seattle/Tacoma Intl

21h 06m2 stops Atlanta Hartsfield-Jackson Denver Intl

20:09 - 17:12SEA Seattle/Tacoma Intl-IAD Washington, D.C. Dulles Intl

18h 03m2 stops Los Angeles Atlanta Hartsfield-Jackson

£265Frontier

Mon, 16 Nov - Mon, 23 Nov

17:17 - 20:13IAD Washington, D.C. Dulles Intl-SEA Seattle/Tacoma Intl

5h 56mdirect

08:15 - 16:13SEA Seattle/Tacoma Intl-IAD Washington, D.C. Dulles Intl

4h 58mdirect

£267Alaska Airlines

Thu, 5 Nov - Sun, 8 Nov

17:17 - 20:13IAD Washington, D.C. Dulles Intl-SEA Seattle/Tacoma Intl

5h 56mdirect

08:07 - 16:14SEA Seattle/Tacoma Intl-IAD Washington, D.C. Dulles Intl

5h 07mdirect

£282Alaska Airlines

Thu, 5 Nov - Tue, 10 Nov

07:05 - 09:56IAD Washington, D.C. Dulles Intl-SEA Seattle/Tacoma Intl

5h 51mdirect

16:30 - 00:20SEA Seattle/Tacoma Intl-IAD Washington, D.C. Dulles Intl

4h 50mdirect

£283Delta

Thu, 5 Nov - Tue, 10 Nov

07:46 - 10:36IAD Washington, D.C. Dulles Intl-SEA Seattle/Tacoma Intl

5h 50mdirect

08:07 - 16:14SEA Seattle/Tacoma Intl-IAD Washington, D.C. Dulles Intl

5h 07mdirect

£284Alaska Airlines

Thu, 5 Nov - Tue, 10 Nov

07:46 - 10:36IAD Washington, D.C. Dulles Intl-SEA Seattle/Tacoma Intl

5h 50mdirect

08:07 - 16:14SEA Seattle/Tacoma Intl-IAD Washington, D.C. Dulles Intl

5h 07mdirect

£285Alaska Airlines

Sat, 5 Dec - Thu, 10 Dec

15:14 - 21:58IAD Washington, D.C. Dulles Intl-SEA Seattle/Tacoma Intl

9h 44m1 stop Los Angeles

08:09 - 16:08SEA Seattle/Tacoma Intl-IAD Washington, D.C. Dulles Intl

4h 59mdirect

£289United Airlines

Fri, 6 Nov - Sun, 8 Nov

17:50 - 20:56IAD Washington, D.C. Dulles Intl-SEA Seattle/Tacoma Intl

6h 06mdirect

22:56 - 08:49SEA Seattle/Tacoma Intl-IAD Washington, D.C. Dulles Intl

6h 53m1 stop Chicago O'Hare Intl

£292United Airlines

Sat, 5 Dec - Thu, 10 Dec

15:14 - 21:58IAD Washington, D.C. Dulles Intl-SEA Seattle/Tacoma Intl

9h 44m1 stop Los Angeles

07:00 - 17:32SEA Seattle/Tacoma Intl-IAD Washington, D.C. Dulles Intl

7h 32m1 stop Chicago O'Hare Intl

£296United Airlines

Recent last minute flight deals from Washington, D.C. to Seattle

Sat, 10 Oct - Sun, 1 Nov

19:24 - 09:28IAD Washington, D.C. Dulles Intl-SEA Seattle/Tacoma Intl

17h 04m1 stop San Diego

08:07 - 16:14SEA Seattle/Tacoma Intl-IAD Washington, D.C. Dulles Intl

5h 07mdirect

£500Alaska Airlines

Sat, 10 Oct - Mon, 2 Nov

19:24 - 09:28IAD Washington, D.C. Dulles Intl-SEA Seattle/Tacoma Intl

17h 04m1 stop San Diego

19:46 - 17:40SEA Seattle/Tacoma Intl-IAD Washington, D.C. Dulles Intl

18h 54m1 stop San Diego

£507Alaska Airlines

Sat, 10 Oct - Sat, 7 Nov

09:38 - 12:20IAD Washington, D.C. Dulles Intl-SEA Seattle/Tacoma Intl

5h 42mdirect

21:49 - 05:44SEA Seattle/Tacoma Intl-IAD Washington, D.C. Dulles Intl

4h 55mdirect

£519Alaska Airlines

Thu, 8 Oct - Thu, 15 Oct

07:05 - 09:56IAD Washington, D.C. Dulles Intl-SEA Seattle/Tacoma Intl

5h 51mdirect

14:50 - 22:49SEA Seattle/Tacoma Intl-IAD Washington, D.C. Dulles Intl

4h 59mdirect

£519Delta

Sat, 10 Oct - Sun, 1 Nov

09:38 - 12:20IAD Washington, D.C. Dulles Intl-SEA Seattle/Tacoma Intl

5h 42mdirect

08:07 - 16:14SEA Seattle/Tacoma Intl-IAD Washington, D.C. Dulles Intl

5h 07mdirect

£526Alaska Airlines

Thu, 8 Oct - Thu, 15 Oct

07:05 - 09:56IAD Washington, D.C. Dulles Intl-SEA Seattle/Tacoma Intl

5h 51mdirect

23:50 - 11:21SEA Seattle/Tacoma Intl-IAD Washington, D.C. Dulles Intl

8h 31m1 stop Minneapolis St Paul

£527Delta

Sat, 10 Oct - Sat, 7 Nov

13:05 - 15:51IAD Washington, D.C. Dulles Intl-SEA Seattle/Tacoma Intl

5h 46mdirect

05:05 - 17:55SEA Seattle/Tacoma Intl-IAD Washington, D.C. Dulles Intl

9h 50m1 stop Denver Intl

£534United Airlines

Thu, 8 Oct - Thu, 15 Oct

06:05 - 11:00IAD Washington, D.C. Dulles Intl-SEA Seattle/Tacoma Intl

7h 55m1 stop Detroit Metropolitan Wayne County

23:50 - 11:21SEA Seattle/Tacoma Intl-IAD Washington, D.C. Dulles Intl

8h 31m1 stop Minneapolis St Paul

£535Delta

Sat, 10 Oct - Sun, 1 Nov

13:05 - 15:51IAD Washington, D.C. Dulles Intl-SEA Seattle/Tacoma Intl

5h 46mdirect

12:28 - 05:19SEA Seattle/Tacoma Intl-IAD Washington, D.C. Dulles Intl

13h 51m2 stops Los Angeles Denver Intl

£538United Airlines

Sat, 10 Oct - Sat, 24 Oct

19:24 - 09:28IAD Washington, D.C. Dulles Intl-SEA Seattle/Tacoma Intl

17h 04m1 stop San Diego

15:56 - 23:59SEA Seattle/Tacoma Intl-IAD Washington, D.C. Dulles Intl

5h 03mdirect

£545Alaska Airlines

Recent direct flight deals from Washington, D.C. to Seattle

Mon, 16 Nov - Mon, 23 Nov

17:17 - 20:13IAD Washington, D.C. Dulles Intl-SEA Seattle/Tacoma Intl

5h 56mdirect

08:15 - 16:13SEA Seattle/Tacoma Intl-IAD Washington, D.C. Dulles Intl

4h 58mdirect

£267Alaska Airlines

Thu, 5 Nov - Sun, 8 Nov

17:17 - 20:13IAD Washington, D.C. Dulles Intl-SEA Seattle/Tacoma Intl

5h 56mdirect

08:07 - 16:14SEA Seattle/Tacoma Intl-IAD Washington, D.C. Dulles Intl

5h 07mdirect

£282Alaska Airlines

Thu, 5 Nov - Mon, 9 Nov

07:05 - 09:56IAD Washington, D.C. Dulles Intl-SEA Seattle/Tacoma Intl

5h 51mdirect

16:30 - 00:20SEA Seattle/Tacoma Intl-IAD Washington, D.C. Dulles Intl

4h 50mdirect

£283Delta

Thu, 5 Nov - Sun, 8 Nov

07:46 - 10:36IAD Washington, D.C. Dulles Intl-SEA Seattle/Tacoma Intl

5h 50mdirect

08:07 - 16:14SEA Seattle/Tacoma Intl-IAD Washington, D.C. Dulles Intl

5h 07mdirect

£284Alaska Airlines

Thu, 5 Nov - Mon, 9 Nov

07:46 - 10:36IAD Washington, D.C. Dulles Intl-SEA Seattle/Tacoma Intl

5h 50mdirect

21:49 - 05:44SEA Seattle/Tacoma Intl-IAD Washington, D.C. Dulles Intl

4h 55mdirect

£285Alaska Airlines

Fri, 6 Nov - Mon, 9 Nov

07:05 - 09:56IAD Washington, D.C. Dulles Intl-SEA Seattle/Tacoma Intl

5h 51mdirect

16:30 - 00:20SEA Seattle/Tacoma Intl-IAD Washington, D.C. Dulles Intl

4h 50mdirect

£299Delta

Fri, 6 Nov - Mon, 9 Nov

07:05 - 09:56IAD Washington, D.C. Dulles Intl-SEA Seattle/Tacoma Intl

5h 51mdirect

16:30 - 00:20SEA Seattle/Tacoma Intl-IAD Washington, D.C. Dulles Intl

4h 50mdirect

£300Delta

Fri, 13 Nov - Mon, 16 Nov

17:50 - 20:56IAD Washington, D.C. Dulles Intl-SEA Seattle/Tacoma Intl

6h 06mdirect

08:09 - 16:08SEA Seattle/Tacoma Intl-IAD Washington, D.C. Dulles Intl

4h 59mdirect

£301United Airlines

Thu, 5 Nov - Tue, 10 Nov

07:05 - 09:56IAD Washington, D.C. Dulles Intl-SEA Seattle/Tacoma Intl

5h 51mdirect

16:30 - 00:20SEA Seattle/Tacoma Intl-IAD Washington, D.C. Dulles Intl

4h 50mdirect

£302Delta

Thu, 14 Jan - Fri, 22 Jan

17:30 - 20:33IAD Washington, D.C. Dulles Intl-SEA Seattle/Tacoma Intl

6h 03mdirect

08:30 - 16:27SEA Seattle/Tacoma Intl-IAD Washington, D.C. Dulles Intl

4h 57mdirect

£304Alaska Airlines

Booking Insights

KAYAK’s insights & trends for Washington, D.C. to Seattle flights

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

Prices

Airlines

How much is a return flight from Washington, D.C. Dulles Intl Airport to Seattle? This analysis is based on the cheapest return trip price found on KAYAK in the last 12 months by searching for a flight from Washington, D.C. Dulles Intl Airport to Seattle departing in November.
What is the cheapest month to fly from Washington, D.C. Dulles Intl Airport to Seattle? To calculate monthly average prices, KAYAK takes all prices for each month over the last year for round-trip flights from Washington, D.C. Dulles Intl Airport to Seattle, 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 Washington, D.C. Dulles Intl Airport to Seattle is January, where tickets cost £171 (return) on average. On the other hand, the most expensive months are June and July, where the average cost of round-trip tickets is £408 and £387 respectively.
How far in advance should I book a flight from Washington, D.C. Dulles Intl Airport to Seattle? To calculate weekly average prices, KAYAK takes all prices for each week before departure over the last year for round-trip flights from Washington, D.C. Dulles Intl Airport to Seattle, removes the top 0.1% to account for outliers, and then takes the average of all the values for each week.: To get a below average price on the flight from Washington, D.C. Dulles Intl Airport to Seattle, you should book around 4 weeks before departure, which saves you about 59% compared to booking last minute. For the absolute cheapest price, our data suggests you should book 4 weeks before departure.

Find deals

Low season	January
High season	July
Cheapest flight	£154

Best time to beat the crowds (45% less expensive on average)

Most popular time to fly (26% more expensive on average)

Flight from Washington, D.C. to Seattle

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

Are your dates flexible? Find out the best times to travel from Washington, D.C. to Seattle based on our flight data from the last year. Discover the cheapest month and even day to fly.

Estimated return price

KAYAK looks at all historical flight data for each date to provide a predicted price for one-way trips or returns 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.

Verified travelerFlew with Alaska Airlines-Jun 2026

If you have a layover in Washington DC, check out any of the Smithsonian museums which are free.

Verified travelerFlew with Alaska Airlines-Sept 2024

Pay the money if can afford to upgrade your seats

Verified travelerFlew with Alaska Airlines-Jul 2024

Dulles, like Seattle has a tram. That can be surprising. The TSA at Seattle is notoriously LONG, however, both times in the last year that I have flown, that has not been the case. At Dulles, the TSA lines were efficient as well. The airport interior is well marked for getting around. I did note that the garbages were full in the Southwest and Alaska areas- as we were there 6 hours and had lots of time to notice nit-picky things that nobody else would care about :). It was convenient to have a "charging station" nearby the Alaska waiting area (right across from our gate). It had 3 ports, and I noticed that as soon as I unplugged mine, it was jumped right on. Suggestion- have Dulles add a few more for passengers who need to recharge phones. Great experience, thank you.

Verified travelerFlew with Alaska Airlines-May 2024

Get to the airport early, especially on holidays

What is the cheapest flight from Washington, D.C. Dulles Intl Airport to Seattle?
In the last 5 days, the lowest price for a flight from Washington, D.C. Dulles Intl Airport to Seattle was £154 for a one-way ticket and £262 for a return.
Which airports will I be using when flying from Washington, D.C. to Seattle?
On your way to Seattle, you’ll fly out from Washington, D.C. Dulles Intl. You’ll be landing at Seattle/Tacoma Intl.
Which airlines offer Wi-Fi service onboard planes from Washington, D.C. to Seattle?
Alaska Airlines, Delta, JetBlue, and American Airlines offer inflight Wi-Fi service on the Washington, D.C. to Seattle flight route.
Which aircraft models fly most regularly from Washington, D.C. to Seattle?
The Boeing 737 is the aircraft model that flies most regularly on the Washington, D.C. to Seattle flight route.
On which days can I fly direct from Washington, D.C. to Seattle?
There are direct flights from Washington, D.C. to Seattle on a daily basis.
How does KAYAK find such low prices on flights from Washington, D.C. to Seattle?
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 Washington, D.C. to Seattle.
How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Washington, D.C. to Seattle?
KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to Seattle from Washington, D.C. 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 Washington, D.C. to Seattle?
Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional return ticket. You could then fly to Seattle with an airline and back to Washington, D.C. with another airline.
What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Washington, D.C. to Seattle?
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 Seattle from Washington, D.C. up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

Direct departures

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

Monday