SEA - WAS

C$ 231 Find Cheap Flights from Seattle to Washington, D.C. – Compare and Save

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1 adult, Economy, 0 bags

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Everything you should know

Cheapest round-trip
C$ 418
Typical prices: C$ 481-C$ 881
Alaska Airlines
Mon 3/12Thu 6/12
SEA - DCA • Direct
Cheapest direct flights
C$ 418
Typical prices: C$ 490-C$ 884
Alaska Airlines
Tue 11/12Fri 14/12
SEA - IAD • Direct
Advice from real travellers
United Economy Plus adds 15 cm more legroom; Priority Boarding helps bin space.
Alaska's baggage guarantee offers miles or a discount if bags miss 20 minutes.
Expert advice
+1
Expert advice
+1
Direct flights
Every day
You can fly direct with Alaska Airlines, Delta, and United Airlines. Average duration is 4h 59m
Direct flights
+1
Direct flights
+1
Top routes
SEA - DCA
Cheapest • 2% average savings
SEA - IAD
Most popular
Insights
Insights
When to book
14 weeks
in advance
Our data shows that travellers who book at least 14 weeks in advance save around 53% compared to booking last minute.
Insights
Insights
When to travel
January
Cheapest • 26% price drop
June
Most popular
Good to know
+1
Good to know
+1
Top layover airports
Detroit Metropolitan Wayne County (DTW)
Cheapest • Avg C$ 384 (round-trip)
Minneapolis St Paul (MSP)
Shortest trip • 7h 26m (one-way)
Insights
Insights
Start a new search
KAYAK searches hundreds of sites at once to find you the best travel deals.
We hope you enjoy your trip to Washington, D.C.!
Flight Deals
Booking Insights
Expert advice
Flight Deals

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

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

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

Thu, 3 Dec - Sun, 6 Dec
Alaska Airlines Logo
8:00 a.m. - 4:05 p.m.SEA  Seattle/Tacoma Intl-DCA Washington, D.C. Reagan-National
5h 05mdirect
Alaska Airlines Logo
5:05 p.m. - 8:22 p.m.DCA  Washington, D.C. Reagan-National-SEA Seattle/Tacoma Intl
6h 17mdirect
C$ 418Alaska Airlines
Thu, 3 Dec - Mon, 7 Dec
Alaska Airlines Logo
2:02 p.m. - 9:59 p.m.SEA  Seattle/Tacoma Intl-DCA Washington, D.C. Reagan-National
4h 57mdirect
Alaska Airlines Logo
5:05 p.m. - 8:22 p.m.DCA  Washington, D.C. Reagan-National-SEA Seattle/Tacoma Intl
6h 17mdirect
C$ 418Alaska Airlines
Thu, 3 Dec - Wed, 9 Dec
Delta Logo
7:20 a.m. - 3:06 p.m.SEA  Seattle/Tacoma Intl-DCA Washington, D.C. Reagan-National
4h 46mdirect
Delta Logo
4:25 p.m. - 7:45 p.m.DCA  Washington, D.C. Reagan-National-SEA Seattle/Tacoma Intl
6h 20mdirect
C$ 418Delta
Fri, 11 Dec - Mon, 14 Dec
Delta Logo
7:20 a.m. - 3:06 p.m.SEA  Seattle/Tacoma Intl-DCA Washington, D.C. Reagan-National
4h 46mdirect
Delta Logo
4:25 p.m. - 7:45 p.m.DCA  Washington, D.C. Reagan-National-SEA Seattle/Tacoma Intl
6h 20mdirect
C$ 418Delta
Fri, 4 Dec - Sun, 6 Dec
Alaska Airlines Logo
2:02 p.m. - 9:59 p.m.SEA  Seattle/Tacoma Intl-DCA Washington, D.C. Reagan-National
4h 57mdirect
Alaska Airlines Logo
8:00 a.m. - 11:17 a.m.DCA  Washington, D.C. Reagan-National-SEA Seattle/Tacoma Intl
6h 17mdirect
C$ 418Alaska Airlines
Sat, 12 Dec - Tue, 15 Dec
Alaska Airlines Logo
8:00 a.m. - 4:05 p.m.SEA  Seattle/Tacoma Intl-DCA Washington, D.C. Reagan-National
5h 05mdirect
Alaska Airlines Logo
5:05 p.m. - 8:22 p.m.DCA  Washington, D.C. Reagan-National-SEA Seattle/Tacoma Intl
6h 17mdirect
C$ 418Alaska Airlines
Wed, 2 Dec - Sat, 5 Dec
Alaska Airlines Logo
2:02 p.m. - 9:59 p.m.SEA  Seattle/Tacoma Intl-DCA Washington, D.C. Reagan-National
4h 57mdirect
Alaska Airlines Logo
5:05 p.m. - 8:22 p.m.DCA  Washington, D.C. Reagan-National-SEA Seattle/Tacoma Intl
6h 17mdirect
C$ 418Alaska Airlines
Fri, 11 Dec - Mon, 14 Dec
Alaska Airlines Logo
8:15 a.m. - 4:15 p.m.SEA  Seattle/Tacoma Intl-IAD Washington, D.C. Dulles Intl
5h 00mdirect
Alaska Airlines Logo
5:18 p.m. - 8:27 p.m.IAD  Washington, D.C. Dulles Intl-SEA Seattle/Tacoma Intl
6h 09mdirect
C$ 418Alaska Airlines
Thu, 3 Dec - Sun, 6 Dec
Alaska Airlines Logo
9:40 p.m. - 5:35 a.m.SEA  Seattle/Tacoma Intl-IAD Washington, D.C. Dulles Intl
4h 55mdirect
Alaska Airlines Logo
5:18 p.m. - 8:27 p.m.IAD  Washington, D.C. Dulles Intl-SEA Seattle/Tacoma Intl
6h 09mdirect
C$ 418Alaska Airlines
Thu, 3 Dec - Mon, 7 Dec
Alaska Airlines Logo
9:40 p.m. - 5:35 a.m.SEA  Seattle/Tacoma Intl-IAD Washington, D.C. Dulles Intl
4h 55mdirect
Alaska Airlines Logo
5:18 p.m. - 8:27 p.m.IAD  Washington, D.C. Dulles Intl-SEA Seattle/Tacoma Intl
6h 09mdirect
C$ 418Alaska Airlines
Booking Insights

Price, demand, and travel trends for Seattle to Washington, D.C. flights

Use KAYAK data on prices, travel dates, airlines, and seasonal trends to compare options and book flights with more confidence.

How much is a round-trip flight from Seattle to Washington, D.C.?

Round-trip flights from Seattle to Washington, D.C. typically range from C$ 481 to C$ 881. The lowest price found in the past 5 days was C$ 418, on Alaska Airlines.

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

There's little price difference between Seattle to Washington, D.C. routes. They average around C$ 638 round-trip, based on KAYAK data over the past 12 months.

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

Based on deals KAYAK users found in the last 12 months, Thursday is the cheapest day of the week to fly from Seattle to Washington, D.C.. It's 6% cheaper than the average day, while Monday is the most expensive, with prices 26% higher.

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

•January is the cheapest month to fly from Seattle to Washington, D.C. at C$ 474 round-trip.
•November (C$ 791) and June (C$ 781) are the most expensive months.
•The price difference between flying in the cheapest and most expensive months is 66% on average.
This is based on KAYAK aggregated and averaged internal data over the past 12 months.

When are flights from Seattle to Washington, D.C. the cheapest?

Flights from Seattle to Washington, D.C. are cheapest 14 weeks before departure. Booking in this window typically costs about 53% less than the average last-minute fare (within 2 weeks of the flight), based on KAYAK data.

Find deals
Expert advice

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

 
KAYAK teamed up with top travel experts to share the best tips for your journey.
Our travel experts
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.

Read more
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.

Read more

Key details for Seattle to Washington, D.C. flights

Low season

February

Cheapest flight

C$ 231
Beat the crowds with an average 24% drop in traveller numbers.
The most popular month to fly with an average 23% increase in traveller numbers.
One-way flight from Seattle to Washington, D.C. Reagan-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

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. 
Putri ArumFlew with Japan Airlines-Mar 2026
Bring your own foods. There should also be a disclaimer on the ticket that foods will not be provided although this is a relatively long flight.
SuzetteFlew with Alaska Airlines-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-May 2025
Seatac has gnarly traffic right now, took 35min to get from highway exit to the terminal

Your Seattle to Washington, D.C. flight questions, answered

Find helpful answers about this route, including flight times, airports, airlines, and booking tips.

  • What are the earliest and latest flights from Seattle to Washington, D.C.?

    These are the earliest and latest flight times available from Seattle to Washington, D.C.:

    • Earliest: departs at 7:20 am and lands at 12:19 pm
    • Latest: departs at 10:50 pm and lands at 3:49 am.

    The flight takes about 4h 59m.

  • Which cabin classes can I book on flights from Seattle to Washington, D.C.?

    Two cabin classes are available on flights from Seattle to Washington, D.C.:

    • Economy Class
    • First Class

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

    A direct flight from Seattle to Washington, D.C. takes 4h 59m, covering 6,007 km.

  • Do I need a passport to fly from Seattle to Washington, D.C.?

    No, a passport is not required for this domestic route, but you will need another form of identification, such as a driver's licence.

  • How much should I expect to pay for a Seattle to Washington, D.C. flight?

    Round-trip flights from Seattle to Washington, D.C. range from C$ 481 to C$ 881, with an average of C$ 643 over the past 12 months. Anything below C$ 481 counts as a good deal.

  • How expensive are last-minute Seattle to Washington, D.C. flights?

    Last-minute fares on this route (booked within two weeks of departure) run 79% above the C$ 643 route average. Book 14 weeks before departure for the lowest fares.

  • How much can I save by taking a layover when flying from Seattle to Washington, D.C.?

    On this route, layover flights are cheaper than direct options on average. Layover fares average C$ 384 round-trip via Detroit Metropolitan Wayne County (DTW), compared to C$ 652 for direct.

  • What is the standard checked bag allowance on flights from Seattle to Washington, D.C.?

    There is no standard. Checked bag policies vary by airline on this route. Most carriers charge C$ 49–C$ 141 for the first checked bag in economy. Premium fares and elite status bookings typically include a free checked bag.

  • How are flight departures from Seattle to Washington, D.C. spread across the day?

    Morning is the busiest departure period on Seattle to Washington, D.C. flights, with 58% leaving in that window. Afternoon departures account for 28%, Night flights for 14%, and Evening flights for 0%.

  • Have flight prices from Seattle to Washington, D.C. changed much recently?

    Yes. Based on fares seen in the past 5 days, round-trip prices on this route showed a wide range, from about C$ 418 to C$ 2,804. That means the highest observed fare was about 7x higher than the lowest one.

  • Which airlines offer Wi-Fi on Seattle to Washington, D.C. flights?

    Two airlines offer in-flight Wi-Fi on Seattle to Washington, D.C. flights:

    • Alaska Airlines
    • Delta

    Pricing varies by airline and fare class. Some plans are included with the ticket or loyalty program; others are paid add-ons priced by flight length.

  • How are flight prices from Seattle to Washington, D.C. looking right now?

    One-way fares from Seattle to Washington, D.C. are currently lower than usual. Average one-way flight prices are about C$ 237, which is 46% below the typical average for this route.

  • What car rental options are available in Washington, D.C.?

    Since Washington, D.C. is served by multiple airports, car rental options and rates can vary depending on which one you fly into.
    Near Washington, D.C. Reagan-National Airport (DCA) – daily rates averaging C$ 100:

    • Sixt
    • Dollar
    • Hertz
    • Thrifty
    • Alamo

    Near Washington, D.C. Dulles Intl Airport (IAD) – daily rates averaging C$ 99:

    • Hertz
    • Dollar
    • Budget
    • Sixt
    • Thrifty

  • Which airports can I use when flying from Seattle to Washington, D.C.?

    Flights from Seattle to Washington, D.C. usually depart from Seattle/Tacoma Intl (SEA) and may arrive at several airports in Washington, D.C. area, including Washington, D.C. Reagan-National (DCA) and Washington, D.C. Dulles Intl (IAD).

  • Which airports do connecting flights from Seattle to Washington, D.C. pass through?

    One-stop flights from Seattle to Washington, D.C. most commonly connect through:

    • Chicago O'Hare Intl (ORD) – 31% of one-stop connections
    • Denver Intl (DEN) – 30% of one-stop connections
    • Chicago Midway (MDW) – 17% of one-stop connections
    • Las Vegas Harry Reid Intl (LAS) – 7% of one-stop connections

  • Can I save money by using flexible dates for flights from Seattle to Washington, D.C.?

    Yes. Flexible dates can save you up to 26% on flights from Seattle to Washington, D.C.. Thursday is the cheapest departure day at C$ 604 round-trip on average, while Monday is the most expensive at C$ 814, a difference of C$ 210.

    KAYAK's flexible dates feature shows options up to three days before and after your selected dates, making it easier to compare nearby fares.

  • Which airlines fly from Seattle to Washington, D.C.?

    3 airlines operate flights between Seattle and Washington, D.C.. The airlines offering direct flights on this route include:

    • Alaska Airlines
    • Delta
    • United Airlines

  • How much time can I save by choosing a different layover airport when travelling from Seattle to Washington, D.C.?

    Flying via Minneapolis St Paul (MSP) gives the shortest average 1-stop total travel time at 7h 26m, compared with 7h 40m via Detroit Metropolitan Wayne County (DTW) and 7h 42m via Lambert-St Louis (STL).

  • What is the time difference between Seattle and Washington, D.C.?

    Washington, D.C. is 3 hours ahead of Seattle (Eastern Time vs Pacific Time). Plan for the time shift when scheduling connections or first-day activities.

  • Which popular places can I visit in Washington, D.C.?

    Some of the most popular sights in Washington, D.C. are Capital One Arena, National Mall, and Kennedy Center. These are among the most viewed places in Washington, D.C. on KAYAK.

  • Which airlines offer extra legroom and free seat selection on Seattle to Washington, D.C. flights?

    Among airlines operating Seattle to Washington, D.C. flights:

    • Alaska Airlines: offers extra legroom; offers free seat selection
    • Delta: offers extra legroom; offers free seat selection
    • United Airlines: offers extra legroom; offers free seat selection
    • American Airlines: offers free seat selection

    Extra legroom and free seat selection availability depends on fare class and route.

  • Which airlines include bags at no extra cost on Seattle to Washington, D.C. flights?

    Here are some options for this route, based on selected ticket types and cabin classes:

    • Alaska Airlines: a carry-on bag and a checked bag in Economy Class
    • Delta: a carry-on bag and a checked bag in Economy Class
    • United Airlines: a carry-on bag and a checked bag in Economy Class

    Baggage allowance can vary by ticket type, cabin class, route, and airline, so always check the fare details before booking.

Your guide to booking Seattle to Washington, D.C. flights

Get tips on when to book, when to fly, and what to know before your trip.
  • If your dates are flexible, aim for a Thursday departure and avoid flying on Monday. On this route, Thursday flights average C$ 604, about C$ 210 less than Monday fares (26% savings) based on the last 12 months.
  • For the best chance at a low fare, aim to book around 14 weeks before you fly. On this route, that window historically saves about 53% versus last-minute pricing (KAYAK booking data, last 12 months).
  • If you can choose when to travel, plan your Seattle to Washington, D.C. trip for January. Fares historically average C$ 474 round-trip in that month – typically C$ 317 less than the most expensive month, which is November (based on the last 12 months).
  • If you have the time, taking a 1-stop flight through Detroit Metropolitan Wayne County Airport (DTW) can be cheaper than flying direct. The cheapest layover option averages C$ 384 round-trip on this route – about C$ 268 less than direct flights (based on the last 12 months).
  • If you're arriving late at night and need somewhere to stay, check out these hotels close to Washington, D.C. Reagan-National Airport.

    • Hyatt House Washington DC The Wharf
    • Intercontinental Hotels Washington D.C. - The Wharf By IHG
    • Canopy by Hilton Washington D.C - The Wharf

Prefer to fly direct from Seattle 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

More options for your flight from Seattle to Washington, D.C.

Complete your trip to Washington, D.C. with a hotel stay or car rental

Car rentals in Washington, D.C.
Hotels in Washington, D.C.
Vacations in Washington, D.C.