SEA - WAS

C$ 172 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 12/3. 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.

 
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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Everything you should know

Cheapest round-trip
C$ 324
Overall average: C$ 534
Alaska Airlines
Wed 18/2Tue 24/2
SEA - DCA • Direct
Cheapest one-way flights
C$ 172
Typical prices: C$ 257-C$ 586
Frontier
Thu 12/3
SEA - DCA • 1 stop
Our travellers' advice
AI-powered summary based on content written by travel experts and KAYAK users. AI can make mistakes.
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
Alaska Airlines
Cheapest • from C$ 324 (round-trip)
Delta
Best reviews • 7.9 score
Airline reviews
Airline reviews
+1
+1
Airline reviews
Airline reviews
+1
Top routes
SEA
-
DCA
Cheapest • 18% 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 55% compared to booking last minute.
Insights
Insights
Insights
Insights
When to travel
July
Cheapest • 10% price drop
April
Most popular
Good to know
Good to know
+1
+1
Good to know
Good to know
+1
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.!
Flight Deals
Booking Insights
Expert advice
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, 18 Feb - Tue, 24 Feb
Alaska Airlines Logo
1:56 p.m. - 9:59 p.m.
SEA
-
DCA
5h 03mdirect
Alaska Airlines Logo
8:00 a.m. - 10:55 a.m.
DCA
-
SEA
5h 55mdirect
C$ 324Alaska Airlines
Thu, 26 Feb - Mon, 2 Mar
Alaska Airlines Logo
9:45 p.m. - 5:40 a.m.
SEA
-
IAD
4h 55mdirect
Alaska Airlines Logo
6:27 p.m. - 9:35 p.m.
IAD
-
SEA
6h 08mdirect
C$ 324Alaska Airlines
Tue, 17 Mar - Tue, 24 Mar
Hawaiian Airlines Logo
7:10 a.m. - 9:02 p.m.
SEA
-
DCA
10h 52m
1 stop
Hawaiian Airlines Logo
5:00 p.m. - 8:02 p.m.
DCA
-
SEA
6h 02mdirect
C$ 329Hawaiian Airlines
Mon, 23 Feb - Mon, 2 Mar
United Airlines Logo
12:43 p.m. - 11:21 p.m.
SEA
-
IAD
7h 38m
1 stop
United Airlines Logo
5:55 p.m. - 8:56 p.m.
IAD
-
SEA
6h 01mdirect
C$ 332United Airlines
Wed, 25 Mar - Fri, 3 Apr
United Airlines Logo
8:00 a.m. - 4:02 p.m.
SEA
-
IAD
5h 02mdirect
United Airlines Logo
10:10 a.m. - 4:37 p.m.
IAD
-
SEA
9h 27m
1 stop
C$ 338United Airlines
Tue, 31 Mar - Tue, 7 Apr
Alaska Airlines Logo
1:53 p.m. - 9:59 p.m.
SEA
-
DCA
5h 06mdirect
Alaska Airlines Logo
8:00 a.m. - 11:05 a.m.
DCA
-
SEA
6h 05mdirect
C$ 338Alaska Airlines
Tue, 17 Mar - Tue, 24 Mar
Hawaiian Airlines Logo
9:27 a.m. - 5:20 p.m.
SEA
-
IAD
4h 53mdirect
Hawaiian Airlines Logo
7:11 p.m. - 10:02 p.m.
IAD
-
SEA
5h 51mdirect
C$ 350Hawaiian Airlines
Tue, 17 Mar - Tue, 24 Mar
American Airlines Logo
5:30 a.m. - 4:31 p.m.
SEA
-
IAD
8h 01m
1 stop
American Airlines Logo
5:00 a.m. - 11:27 a.m.
IAD
-
SEA
9h 27m
1 stop
C$ 354American Airlines
Wed, 18 Mar - Sat, 21 Mar
Delta Logo
3:55 p.m. - 11:49 p.m.
SEA
-
IAD
4h 54mdirect
Delta Logo
7:00 a.m. - 10:03 a.m.
IAD
-
SEA
6h 03mdirect
C$ 358Delta
Sat, 21 Feb - Sat, 28 Feb
Delta Logo
7:20 a.m. - 3:20 p.m.
SEA
-
DCA
5h 00mdirect
Delta Logo
4:44 p.m. - 7:43 p.m.
DCA
-
SEA
5h 59mdirect
C$ 392Delta
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$ 307 on the route between Seattle (SEA) and Washington, D.C. Reagan-National Airport (DCA). Over the past month, this route was, on average, 18% 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 Wednesdays if you are looking for the best rates. For your return to Seattle, you’ll find the best rates on Wednesdays 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 July, where tickets cost C$ 474 (return) on average. On the other hand, the most expensive months are June and December, where the average cost of round-trip tickets is C$ 621 and C$ 570 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.

Yes, flying with a layover may cost you more time, but you can also save money on the route, with a 1 stop layover the cheapest option at C$ 241 on average.

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 55% compared to booking last minute. For the absolute cheapest price, our data suggests you should book 5 weeks before departure.

Expert advice

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

 
AI-powered summary based on content written by travel experts. AI can make mistakes.
KAYAK teamed up with top travel experts to share the best tips for your journey.
Our travel experts
Harriet Baskas

Harriet Baskas

Expert on Alaska Airlines and SEA

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.

Stefanie Waldek

Stefanie Waldek

Expert on United Airlines and IAD

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.

Good to know

Low seasonJanuary
Cheapest flightC$ 172
Most popular time to fly and prices are also 2% lower on average.
Flight from Seattle to Reagan Washington National 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 Airlines
SEA
-
IAD
May 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 Airlines
SEA
-
IAD
May 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$ 172 for a one-way ticket and C$ 324 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 Delta 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.

  • 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$ 311 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$ 369 and an overall rating of 5.7.

  • 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.

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 8123 reviews
8.5Crew
8.1Boarding
7.9Comfort
7.2Food
7.8Entertainment
Airline reviews

Timing, quality of service, promptness and courtesy of the staff

10.0 ExcellentAjai, Jan 2026
DFW - ATL
Read more Delta reviews

Timing, quality of service, promptness and courtesy of the staff

It was last minute due to weather - considering - it was amazing! Good smiles, friendly staff and they were making sure we knew what was going on when and where.

delta last minute gave me a boarding pass for a different flight with no confirmation that they were changing it

The service from the flight attendants were of supreme quality. They greeted and treated everyone with a wide smile. This is totally absent nowadays. Kudos to them!!!!

Excellent flight and got us around tough weather. Only issue was seat TV did not work and crew tried to reboot.

Very large passenger too space from my own seat. Arm board couldn’t be lowered because of his size. It wads very uncomfortable trip, as the flight was full couldn’t move anywhere having back pain because of the position in which I was the entire flight.

was sitting in the jet bridge for 10 minutes in -20 degree weather waiting for my bag

Outdated equipment in disrepair, wifi inoperable. Broken seats, taped air vents, generally poor condition, the 717 showed its age and lack of upkeep.

My flight out of Baton Rouge to Atlanta was delayed by a half hour. This got us into Atlanta airport 30 minutes late. I ran through the airport to get to my connecting flight. As I approached the boarding gate, I saw the boarding door was still open and a passenger was being checked in. But when I got to the gate, the boarding agent told me they had already given away my seat and there were no empty seats on that flight. So I had to take a later flight. That has never happened to me before. Very frustrating.

Connection through Atlanta was difficult. Mechanical issue on plane caused a two hour delay. New gate was a mile away.

Very well recently! Frontier is improving and less harrassing customer on luggages! Positive!

Good for a budget airline! It was easy to get on, staff was really nice. Can’t say anything about the food or entertainment because it wasn’t available, which is fine.

I am writing to express my disappointment with my recent Frontier Airlines flight. I was charged $99 at the gate because my bag was said to be too large, yet once onboard there was no available overhead bin space, and I was required to place the bag under the seat in front of me anyway. This made the charge feel unnecessary and unfair. Additionally, before the flight even took off, I was asked to move from the seat I paid for into a middle seat so another passenger and her cat could have my seat to themselves. I was not offered compensation or an explanation for being moved from a paid seat. Between the unexpected bag fee and being forced to give up my seat, this experience fell well below acceptable customer service standards. I would appreciate a review of this situation and appropriate compensation.

It was costly and difficult to check in. $85 to take a small suitcase with me, carry on or checked and $75 on the return trip, Plus $25 if I didn't check my self in check in $25, because I couldn't do it on the kiosk. Small very uncomfortable seats, waited on the runway for near an hour each way. It was my worst flight to date.

It was ok. It was expensive to check 2 bags ($75.00 per bag), and then it took a long time to wait for shuttle to take us from one terminal to the terminal where the plane was taking off at LAX. And all of this for a flight where we had to pay for any food or drink that was not water.

It didn’t happen. I booked it and then was told it wasn’t available and then forced to pay far higher prices for a worse option

A 630departure flight Delayed 6hours! They changed my gate, I moved to the new gate. Had our flight on the screen for 12noon departure. I go get above to eat, check screen again and the flight was gone, no notice no announcement, nothing!! They sent my bag on the flight I wasn’t on, got it back to me 3days later. Thank goodness they did refund my money but I will NEVER fly them again.

Due to weather, my flight was delayed, further delayed, then canceled. I eventually got through to a support person who helped me find a different route out of MSP, but to get to DIA, they didn't want to, but eventually did help with the connection ticket purchase. But even this replacement flight was delayed time and time again, and I would have missed my connecting flights and I didn't want to get stuck in a layover city, so after 12 hours at the airport with two young boys who were very tired, we just cancelled our plans and spent the week at home, instead of Nana's.

Plane and crew on board were fine. Everything else was terrible.

The third party booking with cheapflightsfares was awful. Kayak should NOT partner with them. They sold me a bundle including seat selection and carry-on, but did not book the carry-ons with Frontier, so I’m out of pocket for $414 more while I await resolution.

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

Information on your arrival and departure airports