SEA - WAS

C$ 236 Find Cheap Flights from Seattle to Washington, D.C. – Compare and Save

1 adult
1 adult, Economy, 0 bags

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Everything you should know

Cheapest round-trip
C$ 401
Typical prices: C$ 452-C$ 838
Delta
Mon 15/10Mon 22/10
SEA - IAD • Direct
Cheapest direct flights
C$ 443
Typical prices: C$ 462-C$ 851
Alaska Airlines
Thu 25/10Sun 28/10
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 5h 05m
Direct flights
+1
Direct flights
+1
Top routes
SEA - DCA
Cheapest • 1% average savings
SEA - IAD
Most popular
Insights
Insights
When to book
7 weeks
in advance
Our data shows that travellers who book at least 7 weeks in advance save around 54% compared to booking last minute.
Insights
Insights
When to travel
January
Cheapest • 24% price drop
June
Most popular
Good to know
+1
Good to know
+1
Top layover airports
Denver Intl (DEN)
Cheapest • Avg C$ 463 (round-trip)
Minneapolis St Paul (MSP)
Shortest trip • 7h 26m (one-way)
Insights
Insights
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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.

Tue, 17 Nov - Sun, 22 Nov
Delta Logo
5:35 a.m. - 4:47 p.m.SEA  Seattle/Tacoma Intl-DCA Washington, D.C. Reagan-National
8h 12m1 stop Salt Lake City
Delta Logo
4:25 p.m. - 7:27 p.m.DCA  Washington, D.C. Reagan-National-SEA Seattle/Tacoma Intl
6h 02mdirect
C$ 401Delta
Thu, 15 Oct - Thu, 22 Oct
Delta Logo
2:50 p.m. - 10:49 p.m.SEA  Seattle/Tacoma Intl-IAD Washington, D.C. Dulles Intl
4h 59mdirect
Delta Logo
6:00 a.m. - 2:19 p.m.IAD  Washington, D.C. Dulles Intl-SEA Seattle/Tacoma Intl
11h 19m1 stop Atlanta Hartsfield-Jackson
C$ 401Delta
Fri, 23 Oct - Sat, 24 Oct
Delta Logo
11:50 p.m. - 11:00 a.m.SEA  Seattle/Tacoma Intl-DCA Washington, D.C. Reagan-National
8h 10m1 stop Minneapolis St Paul
Delta Logo
3:00 p.m. - 8:50 p.m.DCA  Washington, D.C. Reagan-National-SEA Seattle/Tacoma Intl
8h 50m1 stop Minneapolis St Paul
C$ 407Delta
Wed, 11 Nov - Sun, 15 Nov
Delta Logo
11:15 p.m. - 8:40 a.m.SEA  Seattle/Tacoma Intl-DCA Washington, D.C. Reagan-National
6h 25m1 stop Detroit Metropolitan Wayne County
Delta Logo
6:05 a.m. - 12:29 p.m.DCA  Washington, D.C. Reagan-National-SEA Seattle/Tacoma Intl
9h 24m1 stop Minneapolis St Paul
C$ 415Delta
Tue, 13 Oct - Tue, 20 Oct
Delta Logo
11:10 p.m. - 10:12 a.m.SEA  Seattle/Tacoma Intl-IAD Washington, D.C. Dulles Intl
8h 02m1 stop Detroit Metropolitan Wayne County
Delta Logo
12:01 p.m. - 4:58 p.m.IAD  Washington, D.C. Dulles Intl-SEA Seattle/Tacoma Intl
7h 57m1 stop Minneapolis St Paul
C$ 415Delta
Sat, 17 Oct - Mon, 26 Oct
Alaska Airlines Logo
3:56 p.m. - 11:59 p.m.SEA  Seattle/Tacoma Intl-IAD Washington, D.C. Dulles Intl
5h 03mdirect
Alaska Airlines Logo
7:24 p.m. - 9:28 a.m.IAD  Washington, D.C. Dulles Intl-SEA Seattle/Tacoma Intl
17h 04m1 stop San Diego
C$ 422Alaska Airlines
Wed, 18 Nov - Sat, 5 Dec
Southwest Logo
6:10 a.m. - 6:55 p.m.SEA  Seattle/Tacoma Intl-DCA Washington, D.C. Reagan-National
9h 45m2 stops Denver Intl Lambert-St Louis
Southwest Logo
9:25 a.m. - 4:45 p.m.DCA  Washington, D.C. Reagan-National-SEA Seattle/Tacoma Intl
10h 20m1 stop Chicago Midway
C$ 422Southwest
Sat, 10 Oct - Tue, 13 Oct
Alaska Airlines Logo
3:56 p.m. - 11:59 p.m.SEA  Seattle/Tacoma Intl-IAD Washington, D.C. Dulles Intl
5h 03mdirect
Alaska Airlines Logo
7:24 p.m. - 9:28 a.m.IAD  Washington, D.C. Dulles Intl-SEA Seattle/Tacoma Intl
17h 04m1 stop San Diego
C$ 429Alaska Airlines
Mon, 16 Nov - Wed, 18 Nov
Southwest Logo
9:10 a.m. - 11:50 p.m.SEA  Seattle/Tacoma Intl-DCA Washington, D.C. Reagan-National
11h 40m2 stops Austin Bergstrom Dallas Love Field
Southwest Logo
2:40 p.m. - 10:50 p.m.DCA  Washington, D.C. Reagan-National-SEA Seattle/Tacoma Intl
11h 10m2 stops Lambert-St Louis Denver Intl
C$ 429Southwest
Mon, 19 Oct - Wed, 28 Oct
Southwest Logo
12:10 a.m. - 2:20 p.m.SEA  Seattle/Tacoma Intl-DCA Washington, D.C. Reagan-National
11h 10m1 stop Chicago Midway
Southwest Logo
11:40 a.m. - 7:05 p.m.DCA  Washington, D.C. Reagan-National-SEA Seattle/Tacoma Intl
10h 25m2 stops Columbus Denver Intl
C$ 431Southwest
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 from Seattle to Washington, D.C. 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. start at C$ 401. Prices are below average for this route right now, with typical round-trip fares ranging from C$ 452 to C$ 838. The lowest price found in the past 5 days was C$ 401 on Delta.

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$ 605 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.?

Thursday is the cheapest day of the week to fly from Seattle to Washington, D.C. and is 9% cheaper than the average day. Monday is the most expensive day with flight prices 24% higher than average. Based on deals found by KAYAK users in the last 12 months.

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$ 461 round-trip.
•June (C$ 773) and July (C$ 675) are the most expensive months.
•The price difference between flying in the cheapest and most expensive months is 67% on average.
This is based on KAYAK aggregated and averaged internal data over the past 12 months.

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

Flights from Seattle to Washington, D.C. are cheapest 7 weeks before departure. Booking in this window typically costs about 54% 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$ 236
Best time to beat the crowds (23% less expensive on average)
Most popular time to fly (27% more expensive on average)
Flights 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 route details based on KAYAK data, including flight times, airports, airlines, and booking questions.

  • 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 are available on the route 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

  • 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 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

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

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

    Only Economy Class is available on flights from Seattle to Washington, D.C..

  • 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$ 463 round-trip via Denver Intl (DEN), compared to C$ 621 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$ 140 for the first checked bag in economy. Premium fares and elite status bookings typically include a free checked bag.

  • 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:

    • Denver Intl (DEN) – 40% of one-stop connections
    • Chicago O'Hare Intl (ORD) – 24% of one-stop connections
    • Chicago Midway (MDW) – 15% of one-stop connections
    • Boston Logan Intl (BOS) – 5% of one-stop connections

    Denver Intl (DEN) handles the largest share of one-stop connections on this route.

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

    Yes. Being flexible with your travel dates can save you up to 27% on the Seattle to Washington, D.C. route. Thursday is the cheapest departure day at C$ 558 round-trip on average, while Monday is the most expensive at C$ 759, a difference of C$ 201. KAYAK's flexible dates feature shows options up to 3 days before and after your selected dates, making it easier to compare nearby fares.

  • 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%.

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

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

  • 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 12:25 pm
    • Latest: departs at 11:14 pm and lands at 4:19 am.

    The flight takes about 5h 05m.

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

    Last-minute fares on this route – booked within 2 weeks of departure – run 81% above the route average of C$ 608. Book 7 weeks before departure for the lowest fares.

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

    A direct flight from Seattle to Washington, D.C. takes 5h 05m, 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 a real ID-compliant driver's license, a state ID, or another TSA-accepted form of identification.

  • 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$ 401 to C$ 2,450. That means the highest observed fare was about 6x higher than the lowest one.

  • 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$ 260, which is 37% below the typical average for this route.

  • 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 31m 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.

  • 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 from around C$ 32:

    • Sixt
    • Dollar
    • Thrifty
    • Alamo
    • Budget

    Near Washington, D.C. Dulles Intl Airport (IAD) – daily rates from around C$ 33:

    • Dollar
    • Budget
    • Hertz
    • Sixt
    • Thrifty

  • 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$ 452 to C$ 838, with an average of C$ 608 over the past 12 months. Anything below C$ 452 counts as a good deal.

  • 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.

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 instead of Monday. On this route, Thursday flights average C$ 558 – about C$ 201 less than Monday (27% savings) based on the last 12 months.
  • For the best chance at a low fare, aim to book around 7 weeks before you fly. On this route, that window historically saves about 54% 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$ 461 round-trip in that month – typically C$ 312 less than the most expensive month, which is June (based on the last 12 months).
  • If you have the time, taking a 1-stop flight through Denver Intl Airport (DEN) can be cheaper than flying direct. The cheapest layover option averages C$ 463 round-trip on this route – about C$ 158 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.