SEA - WAS

C$ 208 Find Cheap Flights from Seattle to Washington, D.C.

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 24/10. 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
1 adult, Economy

KAYAK searches hundreds of travel sites at once for deals on flights to Washington, D.C.

 
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
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Booking Insights
Flight Deals

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

 
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 for you by selecting your travel dates on KAYAK.

Recent round-trip flight deals from Seattle to Washington, D.C.

Wed, 12 Nov - Sat, 22 Nov
Southwest Logo
7:05 a.m. - 10:10 p.m.SEA-IAD
12h 05m2 stops
Southwest Logo
7:45 p.m. - 12:50 a.m.IAD-SEA
8h 05m1 stop
C$ 353Southwest
Find Deal
Fri, 5 Dec - Mon, 8 Dec
Southwest Logo
6:35 a.m. - 8:30 p.m.SEA-DCA
10h 55m1 stop
Southwest Logo
6:00 a.m. - 1:25 p.m.DCA-SEA
10h 25m1 stop
C$ 355Southwest
Find Deal
Thu, 8 Jan - Sat, 24 Jan
Alaska Airlines Logo
8:00 a.m. - 4:15 p.m.SEA-DCA
5h 15mdirect
Alaska Airlines Logo
8:00 a.m. - 10:55 a.m.DCA-SEA
5h 55mdirect
C$ 356Alaska Airlines
Find Deal
Thu, 8 Jan - Wed, 21 Jan
Alaska Airlines Logo
9:55 a.m. - 5:55 p.m.SEA-IAD
5h 00mdirect
Alaska Airlines Logo
6:55 p.m. - 9:40 p.m.IAD-SEA
5h 45mdirect
C$ 356Alaska Airlines
Find Deal
Wed, 7 Jan - Wed, 21 Jan
United Airlines Logo
5:00 a.m. - 4:35 p.m.SEA-IAD
8h 35m1 stop
United Airlines Logo
5:35 p.m. - 8:37 p.m.IAD-SEA
6h 02mdirect
C$ 364United Airlines
Find Deal
Wed, 5 Nov - Wed, 12 Nov
United Airlines Logo
8:00 a.m. - 4:07 p.m.SEA-IAD
5h 07mdirect
United Airlines Logo
6:30 a.m. - 11:28 a.m.IAD-SEA
7h 58m1 stop
C$ 370United Airlines
Find Deal
Tue, 23 Sep - Thu, 25 Sep
Frontier Logo
7:00 a.m. - 9:59 p.m.SEA-DCA
11h 59m1 stop
Frontier Logo
1:00 p.m. - 12:30 a.m.DCA-SEA
14h 30m1 stop
C$ 375Frontier
Find Deal
Wed, 5 Nov - Sun, 9 Nov
Frontier Logo
12:58 p.m. - 12:04 p.m.SEA-DCA
20h 06m1 stop
Frontier Logo
1:00 p.m. - 12:13 p.m.DCA-SEA
26h 13m1 stop
C$ 414Frontier
Find Deal
Thu, 9 Oct - Tue, 14 Oct
Delta Logo
4:48 p.m. - 12:40 a.m.SEA-IAD
4h 52mdirect
Delta Logo
7:35 a.m. - 10:28 a.m.IAD-SEA
5h 53mdirect
C$ 418Delta
Find Deal
Wed, 22 Oct - Sat, 25 Oct
Delta Logo
7:25 a.m. - 3:28 p.m.SEA-DCA
5h 03mdirect
Delta Logo
4:59 p.m. - 7:50 p.m.DCA-SEA
5h 51mdirect
C$ 425Delta
Find Deal

Everything you should know

Our travellers' advice
AI-generated summary based on content written by travel experts and KAYAK users
Alaska's 20-minute baggage guarantee offers rewards.
Expect traffic delays near Seattle/Tacoma Intl Airport.
Expert advice
Expert advice
+1
+1
Expert advice
Expert advice
+1
Top airlines
Southwest
Cheapest • from C$ 353 (round-trip)
Delta
Best reviews • 7.9 score
Airline reviews
Airline reviews
+1
+1
Airline reviews
Airline reviews
+1
Top routes
SEA-DCA
Cheapest • 30% average savings
SEA-IAD
Most popular
Insights
Insights
Insights
Insights
When to book
4 weeks
in advance
Our data shows that travellers who book at least 4 weeks in advance save around 46% compared to booking last minute.
Insights
Insights
Insights
Insights
When to travel
September
Cheapest • 16% price drop
April
Most popular
Good to know
Good to know
+1
+1
Good to know
Good to know
+1
Cheapest round-trip
C$ 353
Overall average: C$ 522
Southwest
Wed 12/11Sat 22/11
SEA - IAD • 2 stops
Cheapest direct flights
C$ 356
Typical prices: C$ 528-828
Alaska Airlines
Thu 8/1Sat 24/1
SEA - DCA • Direct
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 Washington, D.C.!
Expert advice

Expert advice for your flight from Seattle to Washington, D.C.

 
Snippets provided in this section are AI-generated based on a summarisation of KAYAK-commissioned articles. The articles are presented as-is, for general informational purposes only, and may not be up-to-date. The opinions contained in the articles are original to the author and reflect their authentic experience, which may vary significantly from the experience of others.
KAYAK teamed up with top travel experts to share the best tips for your journey.
Airlines
Alaska Airlines

Alaska's 20-minute baggage guarantee offers a discount or 2,500 miles if delayed.


Enjoy free wine tastings in Washington with your boarding pass and Mileage Plan membership.

United Airlines

Opt for Economy Plus for 15 cm more legroom than standard economy seats.


Purchase Priority Boarding to ensure overhead bin space, placing you in Zone 2.

Airports
SEA

Use the SEA Spot Saver for expedited security screening without a paid program. Book online or via the flySEA app.

Read more about SEAby Harriet Baskas
IAD

The Silver Line Metro connects IAD to downtown D.C. in about 50 minutes, offering a convenient and cost-effective option.

Read more about IADby Stefanie Waldek
Our travel experts
Harriet Baskas

Harriet Baskas

Expert on Alaska Airlines and SEA

Harriet Baskas

Harriet Baskas

Harriet is an award-winning journalist who is happiest in an airport or an unusual museum. Her stories about airports, air travel, and the business of travel have appeared on NBC News, CNBC, USA TODAY, The Points Guy and other outlets. She is the creator of the StuckatTheAirport.com blog and the author of nine books. When not out on the road or exploring the latest airport amenities, she’s home in Seattle getting ready for the next adventure.

Read more
Stefanie Waldek

Stefanie Waldek

Expert on United Airlines and IAD

Stefanie Waldek

Stefanie Waldek

Stefanie Waldek is a freelance space, travel, and design writer based in Saratoga Springs, NY. Her words have appeared in Space.com, Travel + Leisure, Condé Nast Traveler, Architectural Digest, and House Beautiful, among other publications. An expert in aviation and expedition cruising, Stefanie is frequently up in the air or on the sea, likely en route to Antarctica or the Arctic.

Read more
Booking Insights

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

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 Seattle to Washington, D.C. flight route?

Data is based on round-trip flight searches on KAYAK over the past month.

The cheapest return flight from Seattle to Washington, D.C. costs C$ 206 on the route between Seattle (SEA) and Washington, D.C. Reagan-National Airport (DCA). Over the past month, this route was, on average, 30% cheaper than other Seattle-Washington, D.C. routes. The most popular route is between Seattle (SEA) and Washington, D.C. Dulles Intl Airport (IAD).

What’s the cheapest day of the week to fly from Seattle to Washington, D.C.?

The average price of all round-trip flights from Seattle to Washington, D.C. clicked on KAYAK for each day over the last 12 months.

When flying from Seattle to Washington, D.C., you should consider leaving on a Thursday and avoid Sundays if you are looking for the best rates. For your return to Seattle, you’ll find the best rates on Tuesdays and the most expensive ones on Saturdays.

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

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for round-trip flights from Seattle to Washington, D.C., 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. is September, where tickets cost C$ 453 (return) on average. On the other hand, the most expensive months are December and June, where the average cost of round-trip tickets is C$ 704 and C$ 629 respectively.

Can I save money by flying with a layover from Seattle to Washington, D.C.?

The average round-trip price for all non-stop flights, flights with one layover, and flights with two layovers for the route found by users searching on KAYAK in the last 2 weeks.

No, with an average price for the route of C$ 349, prices are generally cheapest when you fly direct.

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

To calculate weekly average prices, KAYAK takes all prices for each week before departure over the last year for round-trip flights from Seattle to Washington, D.C., 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 Seattle to Washington, D.C., you should book around 4 weeks before departure, which saves you about 46% compared to booking last minute. For the absolute cheapest price, our data suggests you should book 6 weeks before departure.

Good to know

Low seasonFebruary
Cheapest flightC$ 208
Best time to beat the crowds (4% less expensive on average)
Most popular time to fly and prices are also 2% lower 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.

Flights from Seattle to Washington, D.C.: the best tips from KAYAK users' own experiences

Insights shared by verified travellers who flew the route from Seattle to Washington, D.C. 
SuzetteFlew with Alaska AirlinesSEA-IADMay 2025
Take a shower before arriving at airport and don't wear perfume at all! Pack bags tight, so boarding is smooth and quick.
DanielFlew with Alaska AirlinesSEA-IADMay 2025
Seatac has gnarly traffic right now, took 35min to get from highway exit to the terminal

FAQs for booking flights from Seattle to Washington, D.C.

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

    In the last 3 days, the lowest price for a flight from Seattle to Washington, D.C. was C$ 150 for a one-way ticket and C$ 255 for a round-trip.

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

    On your way to Washington, D.C., you’ll fly out from Seattle/Tacoma Intl. You’ll be landing in one of Washington, D.C.’s 2 airports: Washington, D.C. Reagan-National or Washington, D.C. Dulles Intl.

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

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

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

    The Boeing 737-800 Passenger/BBJ2 (winglets) is the aircraft model that flies most regularly on the Seattle to Washington, D.C. flight route.

  • Which airline alliances offer flights from Seattle to Washington, D.C.?

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

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

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

  • Which is the best airline for flights from Seattle to Washington, D.C., Delta or Frontier?

    The two airlines most popular with KAYAK users for flights from Seattle to Washington, D.C. are Delta and Frontier. With an average price for the route of C$ 315 and an overall rating of 7.9, Delta is the most popular choice. Frontier is also a great choice for the route, with an average price of C$ 340 and an overall rating of 5.8.

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

    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, D.C..

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

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

  • What is the Hacker Fare option on flights from Seattle to Washington, D.C.?

    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, D.C. 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, D.C.?

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

KAYAK’s 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$ 824 or less one-way and C$ 285 or less round-trip.

Prefer to fly direct from Seattle to Washington, D.C.?

 
Direct data is based off flight results for the next 60 days. Find direct flights from all airlines flying direct from Seattle/Tacoma Intl to Washington, D.C..
Find which airlines fly direct from Seattle/Tacoma Intl Airport to Washington, D.C., which days they fly and book direct flights.

Direct departures

Seattle/Tacoma Intl to Washington, D.C.

Monday

Alaska Airlines,Delta,United Airlines

Alaska Airlines,Delta, +1 more

Tuesday

Alaska Airlines,Delta,United Airlines

Alaska Airlines,Delta, +1 more

Wednesday

Alaska Airlines,Delta,United Airlines

Alaska Airlines,Delta, +1 more

Thursday

Alaska Airlines,Delta,United Airlines

Alaska Airlines,Delta, +1 more

Friday

Alaska Airlines,Delta,United Airlines

Alaska Airlines,Delta, +1 more

Saturday

Alaska Airlines,Delta,United Airlines

Alaska Airlines,Delta, +1 more

Sunday

Alaska Airlines,Delta,United Airlines

Alaska Airlines,Delta, +1 more

See more nonstop flights

Direct returns

Washington, D.C. to Seattle/Tacoma Intl

Monday

Alaska Airlines,Delta,United Airlines

Alaska Airlines,Delta, +1 more

Tuesday

Alaska Airlines,Delta,United Airlines

Alaska Airlines,Delta, +1 more

Wednesday

Alaska Airlines,Delta,United Airlines

Alaska Airlines,Delta, +1 more

Thursday

Alaska Airlines,Delta,United Airlines

Alaska Airlines,Delta, +1 more

Friday

Alaska Airlines,Delta,United Airlines

Alaska Airlines,Delta, +1 more

Saturday

Alaska Airlines,Delta,United Airlines

Alaska Airlines,Delta, +1 more

Sunday

Alaska Airlines,Delta,United Airlines

Alaska Airlines,Delta, +1 more

See more nonstop flights

Reviews of the top airlines 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.
7.9
DeltaOverall score based on 7960 reviews
7.9Entertainment
7.3Food
8.2Boarding
7.9Comfort
8.5Crew
Airline reviews

Perfect flight both ways. On time, courteous staff, plane comfortable and cool. Best domestic flights I’ve had in awhile.

10.0 ExcellentAnonymous, Sep 2025CLT - BOS
Read more Delta reviews

Perfect flight both ways. On time, courteous staff, plane comfortable and cool. Best domestic flights I’ve had in awhile.

Really low quality food especially for an international flight. The crew also was surprisingly unpleasant except couple of ladies. I know we were not in first class but that’s no reason to treat customers as less.

Flight delayed for two and half hours and then canceled altogether due to mechanical issues. No mechanic onsite to fix so had to send one from LAX.

Crew was good. The reservation got mixed up and they didn't have my TSA number. I am also a Silver Medallion and wasn't able to use Sky Priority.

Delta made it easy, comfortable and timely. The crew was fantastic.

This route with Delta always has delays or is cancelled. Aircrafts seem smaller and older. I fly Delta quite a bit - haven’t had issues with the international flights. But this route has always been the troublesome one

Three seats in first class were broken and while they were able to still acommodate us it was looking very touch and go and they had others they could not acommodate

Mechanic delay in addition to a 2 hour change in takeoff time was frustrating.

Delayed due to thunderstorms and no in-flight service due to rough weather — both of which are out of Delta’s control. Flight was good overall.

The flight attendants in SLC were rude. I arrived 40 minutes early to gate. Ticket said I needed check in for seat assignments and tried check in and attendants said they weren’t doing it. And proceeded to never call me to give me a ticket so when time to board I received the very last seat. Please relay to employees to do their job better..,

Seats were new and comfortable. Staff was fine. Missed my connection due to weather -which wasn’t their fault- but got no help at all. Gate staff sent me to customer service, which was and stayed unstaffed. Sign with QR code directed me to call or chat. Chat was useless. Call was returned after an hour. No itinerary offered by Frontier could get me home in less than 30 hours. Rebooked with another airline and got a partial refund that came to about 10 percent of what I paid to get home.

Finally a Frontier on time and efficient. I've had problems before with your airline, but this time everything went fine.

The experience was good. No frills but I got there safe and sound and on time.

Great for the price. No wifi or entertainment, but gate agents and crew were fantastic and we boarded quickly and left on time.

sluggish boarding and arrival procedures, fake nice flight attendants, and lots of delays.

Disaster. They lied every step of the way. We ended up being delayed due to crew and then allegedly abandoned the flight because of a curfew at LGA. No rebooking to LGA at any reasonable time. No hotel. No meal vouchers. Had to sleep in the airport and fly to Newark instead. Will never fly Frontier again.

What I expected, nickeled and dined and a frontier flight attendant loudly complained about her job and lack of communication as she headed to the gate on her cell phone. Not professional.

As every law enforcement agency I could imagine surrounded the plane and we didn’t disembark for 2 hours and then had to stick around for another hour to go get our personal belongings after leaving them behind and being bused away from the plane, it was scary and inconvenient. We were given no information as to why this was happening. Lack of communication with passengers was disappointing.

After boarding and un-boarding twice over 6+hours, the flight was canceled.

Severe turbulence. Captain never came on to reassure passengers after things settled down.

Everything you need to know for your flight from Seattle to Washington, D.C.

Information on your arrival and departure airports

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