SEA - IAD

C$ 196 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 16/1. 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, 0 bags

KAYAK searches hundreds of travel sites at once for deals on flights to Washington, D.C. Dulles Intl 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
Travellers love KAYAK
41,299,237 searches in the past 7 days on KAYAK

Save 25% or moreCompare multiple travel sites with one search.

Track pricesNot ready to book? Create a price alert for when prices drop.

Free to useThere are no hidden charges or fees.

Filter your dealsChoose cabin class, free Wi-Fi and more.

Flight Deals
Booking Insights
Expert advice
Flight Deals

Cheap Flights 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 for you by selecting your travel dates on KAYAK.

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

Sat, 6 Dec - Sun, 7 Dec
United Airlines Logo
9:05 a.m. - 8:44 p.m.SEA-IAD
8h 39m1 stop
United Airlines Logo
6:00 a.m. - 11:16 a.m.IAD-SEA
8h 16m1 stop
C$ 352United Airlines
Find Deal
Fri, 12 Dec - Mon, 15 Dec
United Airlines Logo
8:10 a.m. - 4:18 p.m.SEA-IAD
5h 08mdirect
United Airlines Logo
5:55 p.m. - 8:54 p.m.IAD-SEA
5h 59mdirect
C$ 355United Airlines
Find Deal
Tue, 9 Dec - Thu, 11 Dec
Alaska Airlines Logo
7:59 p.m. - 5:30 p.m.SEA-IAD
18h 31m1 stop
Alaska Airlines Logo
5:37 p.m. - 12:12 a.m.IAD-SEA
9h 35m1 stop
C$ 358Alaska Airlines
Find Deal
Thu, 20 Nov - Mon, 24 Nov
Delta Logo
4:59 p.m. - 12:54 a.m.SEA-IAD
4h 55mdirect
Delta Logo
7:15 a.m. - 10:19 a.m.IAD-SEA
6h 04mdirect
C$ 359Delta
Find Deal
Sat, 10 Jan - Fri, 16 Jan
Delta Logo
3:20 p.m. - 11:10 p.m.SEA-IAD
4h 50mdirect
Delta Logo
7:30 a.m. - 10:29 a.m.IAD-SEA
5h 59mdirect
C$ 361Delta
Find Deal
Tue, 10 Feb - Tue, 17 Feb
United Airlines Logo
12:25 p.m. - 11:22 p.m.SEA-IAD
7h 57m1 stop
United Airlines Logo
5:40 p.m. - 11:41 p.m.IAD-SEA
9h 01m1 stop
C$ 362United Airlines
Find Deal
Tue, 30 Dec - Mon, 19 Jan
Alaska Airlines Logo
10:14 p.m. - 6:13 a.m.SEA-IAD
4h 59mdirect
Alaska Airlines Logo
6:04 p.m. - 9:08 p.m.IAD-SEA
6h 04mdirect
C$ 366Alaska Airlines
Find Deal
Mon, 22 Dec - Tue, 6 Jan
United Airlines Logo
10:52 a.m. - 9:21 p.m.SEA-IAD
7h 29m1 stop
United Airlines Logo
5:55 p.m. - 8:57 p.m.IAD-SEA
6h 02mdirect
C$ 367United Airlines
Find Deal
Sat, 6 Dec - Tue, 9 Dec
Southwest Logo
10:15 a.m. - 10:15 p.m.SEA-IAD
9h 00m1 stop
Southwest Logo
7:40 a.m. - 10:55 p.m.IAD-SEA
18h 15m2 stops
C$ 451Southwest
Find Deal
Wed, 3 Dec - Fri, 12 Dec
Southwest Logo
6:15 a.m. - 10:00 p.m.SEA-IAD
12h 45m2 stops
Southwest Logo
5:50 p.m. - 12:05 a.m.IAD-SEA
9h 15m1 stop
C$ 465Southwest
Find Deal

Everything you should know

Our travellers' advice
AI-generated summary based on content written by travel experts and KAYAK users
United's Economy Plus offers more legroom on this route.
Expect traffic delays near Seattle/Tacoma Intl Airport.
Expert advice
Expert advice
+1
+1
Expert advice
Expert advice
+1
Top airlines
United Airlines
Cheapest • from C$ 352 (round-trip)
Alaska Airlines
Best reviews • 8.0 score
Airline reviews
Airline reviews
+1
+1
Airline reviews
Airline reviews
+1
When to book
4 weeks
in advance
Our data shows that travellers who book at least 4 weeks in advance save around 51% compared to booking last minute.
Insights
Insights
Insights
Insights
When to travel
February
Cheapest • 15% price drop
December
Most popular
Good to know
Good to know
+1
+1
Good to know
Good to know
+1
Cheapest round-trip
C$ 352
Overall average: C$ 735
United Airlines
Sat 6/12Sun 7/12
SEA - IAD • 1 stop
Cheapest direct flights
C$ 355
Typical prices: C$ 507-C$ 971
United Airlines
Fri 12/12Mon 15/12
SEA - IAD • 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.!
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’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. Dulles Intl Airport clicked on KAYAK for each day over the last 12 months.

If your flying dates are flexible, you should consider flying to Washington, D.C. on a Thursday, as we generally find the cheapest rates on that day for this route. On the other hand, Sunday is the most expensive day to fly from Seattle to Washington, D.C.. For your return ticket, we recommend flying on a Thursday and avoiding Saturdays for the best deals.

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 round-trip 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$ 481 (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$ 735 and C$ 667 respectively.

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

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. Dulles Intl Airport, 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. Dulles Intl Airport, you should book around 4 weeks before departure, which saves you about 51% compared to booking last minute. For the absolute cheapest price, our data suggests you should book 6 weeks before departure.

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
United Airlines

United's Economy Plus offers up to 15 cm more legroom than standard economy seats.


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

Alaska Airlines

Alaska Airlines' Wine Flies Free program allows free wine case check-in from select airports.


Alaska Airlines' 20-minute baggage guarantee offers compensation if bags delay.

Airports
SEA

Use SEA Spot Saver for expedited security screening. Book online or via the flySEA app for free, available daily from 4 a.m. to 10 p.m.

Read more about SEAby Harriet Baskas
IAD

Take the Silver Line Metro from IAD to D.C. city centre. The ride takes about 50 minutes and is a cost-effective option.

Read more about IADby Stefanie Waldek
Our travel experts
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
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

Good to know

Low seasonFebruary
Cheapest flightC$ 196
Best time to beat the crowds (16% less expensive on average)
Most popular time to fly (29% more expensive on average)
Flight from Seattle to Washington, D.C.

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 Seattle to Washington, D.C. flights

  • 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$ 196 for a one-way ticket and C$ 352 for a round-trip.

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

    All the following airlines offer inflight Wi-Fi service on the Seattle to Washington, D.C. flight route: Alaska Airlines, Hawaiian Airlines, Delta, JetBlue, American Airlines, and Lufthansa.

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

    The Boeing 737 MAX 9 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 is the only airline alliance operating flights between Seattle and Washington, D.C..

  • 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., Alaska Airlines or Hawaiian Airlines?

    The two airlines most popular with KAYAK users for flights from Seattle to Washington, D.C. are Alaska Airlines and Hawaiian Airlines. With an average price for the route of C$ 395 and an overall rating of 8.0, Alaska Airlines is the most popular choice. Hawaiian Airlines is also a great choice for the route, with an average price of C$ 366 and an overall rating of 7.8.

  • 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 travellers 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. Dulles Intl Airport

  • Looking for a cheap flight? 25% of our users found flights on this route for C$ 195 or less one-way and C$ 454 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. Dulles Intl.
Find which airlines fly direct from Seattle/Tacoma Intl Airport to Washington, D.C. Dulles Intl Airport, which days they fly and book direct flights.

Direct departures

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

Direct returns

Washington, D.C. Dulles Intl 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.
8.0
Alaska AirlinesOverall score based on 11206 reviews
8.5Crew
7.1Food
7.0Entertainment
7.8Comfort
8.1Boarding
Airline reviews

Its bumpy but I can say its safe flight ,Thanks Alaska airline for bringing me in my destination😊.

8.0 ExcellentMary Grace, Oct 2025SEA - BNA
Read more Alaska Airlines reviews

Its bumpy but I can say its safe flight ,Thanks Alaska airline for bringing me in my destination😊.

Almost 3 hr delay in Settle with very little information available to passengers. They boarded the plane and we waited for a long time inside the plane as well.

This was our first time flying with Alaska. It was a seamless experience, with comfortable seats and leg room. Staff were friendly and helpful.

Flight on time. Crew good. Seating Bad. Have to pay extra on a not cheap flight to avoid being next to toilet.

The crew was great! Passengers were nice. Just an fyi that I heard several of them complain that the snack was not gluten free. Many people got handed the snack and then promptly gave it back to the flight attendant. Might be good to look into another option as such a high percentage of people in CO and WA are gf. Cheers!

Food and entertainment not applicable - standard drinks and cinnamon cookies; crew did not do a song and dance for us so no entertainment. I like the slightly better leg room than American Airlines - at least it felt that way. Flight crew and atmosphere seemed more welcoming than American, too.

It was fine, mostly I was just happy to be on my last leg home. No in flight entertainment but that's forgivable since it was only a 2 hour flight.

Was delayed in Newark 24 hours due to mechanical problems. The staff was very helpful in trying to make the best of a trying situation. In SeaTac, they changed gates and times. Usually have no problems from SeaTac.

Flight was cancelled, then rebooked on a flight that I was unable to get through since they had closed the gate.

Terrible. We were bumped off our flight to another and weren't sent notice until we were on our prior flight. We got home four hours later and the airline couldn't have cared less.

Canceled my flight within 24 hours, causing me arriving home midnight. Will never book Hawaiian airlines anymore

I like Hawaiian, it was great that they had good internet connection across the Pacific Ocean, thanks to Star Link satellites. The seating was comfortable, ( I was in economy ). Maybe I missed it, but I only got offered a beverage once. It was a nonstop flight KOA to SMF. I would take it again next time I go that way.

I always love flying Hawaii and I have nothing to add

Previously flown Hawaiian Airlines on similar routes, I found Alaska Airlines to be noticeably more comfortable. The seats on Alaska Airlines provided better support and cushioning, which made a significant difference on the long flight to the islands. When you’re spending 5-6 hours in the air, seat comfort really matters, and Alaska Airlines delivered where it counts. After comparing both carriers, I’ve decided to book with Alaska Airlines for all my future Hawaii trips. The superior seat comfort alone makes it worth choosing Alaska over Hawaiian Airlines. If you’re planning a trip to Hawaii and prioritizing comfort, I’d recommend giving Alaska Airlines a try. You won’t be disappointed. Highly recommended for Hawaii travel!

I received several emails about my 3:10 flight. When I showed up to the airport at 12:30 to check my bags I was told the flight was actually at 1 pm. They grudgingly rebooked me for a flight at 5:22 to Vegas to get a connecting to LAX. I did find the gate for my original 3:10 flight but they were booked. I proceeded to receive status updates and gate change information for the 3:10 flight, even though I was apparently never supposed to be on that flight

My flight was delayed three hours and then cancelled. The gate agent proceeded to rebook me in a middle seat without telling me and I was placed between two large individuals who did not fit in their own seats and instead took up most of mine. It was an awful experience.

The food options were limited and very specific. Some type of entertainment option for a 4.5 hour flight would have been nice.

Flight was smooth and comfortable. We were able to check a bag at counter due to full flight and boarded with an earlier group. We were there very early and didn’t hear the gate change just noticed our flight was no longer displayed st the gate. There were two other flights with gate shuffles - may be unavoidable but not desirable. First time I had to print my own luggage tag and attach at arrival. Not a fan of that process.

The crew was EXTREMELY helpful And sweet and the flight was smooth!

I received an email from Kayak with confirmation number for Hawaiian and another for Alaska. I received emails from Kayak for both my outbound and return flight to say "time to check in." Despite trying each number (Hawaiian and Alaska), I could not check in for outbound or return. It was then confusing at the airport - I hda "no place to go" to figure out how to check in. All the kiosks are marked "scan bag,etc." I wandered around with no agent to talk to. That was a bit stressful. Either Kayak, or airline, needed better communication on what to expect and to do.

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

Information on your arrival and departure airports

Not what you’re looking for? Find thousands of other hotels, flights, car rentals and package deals with KAYAK.