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Seattle Tacoma Intl. Airport to Dulles International Airport flight

Explore the cheapest one-way and round-trip flights from Seattle Tacoma Intl. Airport to Dulles International Airport over the next 90 days, with one-way fares from €122 and round-trip from €152. Based on Trip.com's latest 7-day flight data.

      • Cheapest nonstop
        SEA 11:58 AM
        5h 8m
        Nonstop
        IAD 8:06 PM
        Seattle - Washington D.C. | Mon, Nov 9 | Delta Air Lines
        DCA 4:25 PM
        6h 2m
        Nonstop
        SEA 7:27 PM
        Washington D.C. - Seattle | Thu, Nov 12 | Delta Air Lines
        €152 €296
        49% off
        49% off
        €296 €152
      • SEA 3:56 PM
        5h 3m
        Nonstop
        IAD 11:59 PM
        Seattle - Washington D.C. | Tue, Oct 20 | Alaska Airlines
        IAD 7:02 AM
        5h 42m
        Nonstop
        SEA 9:44 AM
        Washington D.C. - Seattle | Mon, Oct 26 | Alaska Airlines
        €156 €296
        47% off
        47% off
        €296 €156
      • SEA 2:50 PM
        4h 59m
        Nonstop
        IAD 10:49 PM
        Seattle - Washington D.C. | Mon, Oct 19 | Delta Air Lines
        IAD 7:05 AM
        5h 51m
        Nonstop
        SEA 9:56 AM
        Washington D.C. - Seattle | Thu, Oct 22 | Delta Air Lines
        €170 €296
        43% off
        43% off
        €296 €170
      • SEA 3:56 PM
        5h 3m
        Nonstop
        IAD 11:59 PM
        Seattle - Washington D.C. | Sat, Oct 17 | Alaska Airlines
        IAD 9:38 AM
        5h 42m
        Nonstop
        SEA 12:20 PM
        Washington D.C. - Seattle | Fri, Oct 23 | Alaska Airlines
        €173
        42% off
        €296 €173
      • SEA 3:56 PM
        5h 3m
        Nonstop
        IAD 11:59 PM
        Seattle - Washington D.C. | Mon, Oct 19 | Alaska Airlines
        IAD 7:02 AM
        5h 42m
        Nonstop
        SEA 9:44 AM
        Washington D.C. - Seattle | Thu, Oct 22 | Alaska Airlines
        €198
        33% off
        €296 €198
      • SEA 3:56 PM
        5h 3m
        Nonstop
        IAD 11:59 PM
        Seattle - Washington D.C. | Sat, Oct 10 | Alaska Airlines
        IAD 7:02 AM
        5h 42m
        Nonstop
        SEA 9:44 AM
        Washington D.C. - Seattle | Sat, Oct 17 | Alaska Airlines
        €198
        33% off
        €296 €198
      • SEA 3:56 PM
        5h 3m
        Nonstop
        IAD 11:59 PM
        Seattle - Washington D.C. | Sun, Oct 4 | Alaska Airlines
        IAD 7:02 AM
        5h 42m
        Nonstop
        SEA 9:44 AM
        Washington D.C. - Seattle | Sat, Oct 10 | Alaska Airlines
        €203
        31% off
        €296 €203
      • SEA 2:52 PM
        5h 4m
        Nonstop
        IAD 10:56 PM
        Seattle - Washington D.C. | Sun, Oct 4 | Delta Air Lines
        IAD 7:05 AM
        5h 51m
        Nonstop
        SEA 9:56 AM
        Washington D.C. - Seattle | Sat, Oct 10 | Delta Air Lines
        €205
        31% off
        €296 €205
      • SEA 2:52 PM
        5h 4m
        Nonstop
        IAD 10:56 PM
        Seattle - Washington D.C. | Mon, Oct 5 | Delta Air Lines
        IAD 7:05 AM
        5h 51m
        Nonstop
        SEA 9:56 AM
        Washington D.C. - Seattle | Sun, Oct 11 | Delta Air Lines
        €207
        30% off
        €296 €207
      • SEA 2:50 PM
        4h 59m
        Nonstop
        IAD 10:49 PM
        Seattle - Washington D.C. | Mon, Oct 26 | Delta Air Lines
        IAD 7:05 AM
        5h 51m
        Nonstop
        SEA 9:56 AM
        Washington D.C. - Seattle | Tue, Nov 3 | Delta Air Lines
        €207
        30% off
        €296 €207
      • SEA 2:50 PM
        4h 59m
        Nonstop
        IAD 10:49 PM
        Seattle - Washington D.C. | Sun, Oct 25 | Delta Air Lines
        IAD 7:05 AM
        5h 51m
        Nonstop
        SEA 9:56 AM
        Washington D.C. - Seattle | Sun, Nov 1 | Delta Air Lines
        €207
        30% off
        €296 €207
      • SEA 7:00 PM
        8h 20m
        1 stop
        IAD 6:20 AM
        Seattle - Washington D.C. | Mon, Oct 19 | Frontier Airlines
        DCA 2:00 PM
        22h 51m
        1 stop
        SEA 9:51 AM
        Washington D.C. - Seattle | Sun, Oct 25 | Frontier Airlines
        €205
        31% off
        €296 €205
      • SEA 1:00 PM
        17h 25m
        1 stop
        WAS 2:00 PM
        Seattle - Washington D.C. | Mon, Oct 5 | Normal Airline
        WAS 3:00 PM
        6h
        Nonstop
        SEA 4:00 PM
        Washington D.C. - Seattle | Wed, Oct 7 | Normal Airline
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      • Cheapest nonstop
        SEA 9:36 PM
        5h 4m
        Nonstop
        IAD 5:40 AM
        Seattle - Washington D.C. | Sat, Nov 7 | Alaska Airlines
        €122 €198
        38% off
        38% off
        €198 €122
      • SEA 9:35 PM
        5h 5m
        Nonstop
        IAD 5:40 AM
        Seattle - Washington D.C. | Wed, Oct 14 | Alaska Airlines
        €123 €198
        38% off
        38% off
        €198 €123
      • SEA 3:56 PM
        5h 3m
        Nonstop
        IAD 11:59 PM
        Seattle - Washington D.C. | Tue, Nov 10 | Alaska Airlines
        €124 €198
        37% off
        37% off
        €198 €124
      • SEA 2:50 PM
        4h 59m
        Nonstop
        IAD 10:49 PM
        Seattle - Washington D.C. | Sat, Nov 7 | Delta Air Lines
        €124
        37% off
        €198 €124
      • SEA 2:52 PM
        5h 4m
        Nonstop
        IAD 10:56 PM
        Seattle - Washington D.C. | Wed, Oct 14 | Delta Air Lines
        €124
        37% off
        €198 €124
      • SEA 2:50 PM
        4h 59m
        Nonstop
        IAD 10:49 PM
        Seattle - Washington D.C. | Tue, Nov 10 | Delta Air Lines
        €134
        32% off
        €198 €134
      • SEA 2:52 PM
        5h 4m
        Nonstop
        IAD 10:56 PM
        Seattle - Washington D.C. | Tue, Oct 13 | Delta Air Lines
        €134
        32% off
        €198 €134
      • SEA 9:36 PM
        5h 4m
        Nonstop
        IAD 5:40 AM
        Seattle - Washington D.C. | Fri, Oct 30 | Alaska Airlines
        €138
        30% off
        €198 €138
      • SEA 10:17 AM
        9h 30m
        1 stop
        IAD 10:47 PM
        Seattle - Washington D.C. | Sun, Oct 18 | American Airlines
        €129
        35% off
        €198 €129
      • SEA 9:45 PM
        29h 35m
        1 stop
        IAD 6:20 AM
        Seattle - Washington D.C. | Tue, Oct 6 | Frontier Airlines
        €137
        31% off
        €198 €137
      • SEA 11:10 PM
        8h 2m
        1 stop
        IAD 10:12 AM
        Seattle - Washington D.C. | Fri, Nov 6 | Delta Air Lines
        €137
        31% off
        €198 €137
      • SEA 5:10 AM
        7h 38m
        1 stop
        IAD 3:48 PM
        Seattle - Washington D.C. | Sun, Nov 15 | American Airlines
        €137
        31% off
        €198 €137
      • SEA 1:00 PM
        17h 25m
        1 stop
        WAS 2:00 PM
        Seattle - Washington D.C. | Mon, Oct 5 | Normal Airline
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Displayed flight fares from Seattle Tacoma Intl. Airport to Dulles International Airport are based on average prices across airlines for the next 3 months, according to the latest Trip.com database.

Trip.com Price Insights: Flights from Seattle Tacoma Intl. Airport to Dulles International Airport

What is the cheapest month for one-way flights from Seattle Tacoma Intl. Airport to Dulles International Airport?

Data is based on average one-way flight prices from Seattle Tacoma Intl. Airport to Dulles International Airport in Trip.com's database over the past 12 months.

Based on Trip.com’s data from the past 12 months, if you’re looking for a low-cost one-way ticket from Seattle Tacoma Intl. Airport to Dulles International Airport, the best time to buy is in July, with an average price of €201. You’ll want to avoid January, when the average price can reach as high as €458.

€458
€330
€201
€73
    Cheapest
  • €426
    Sep
  • €304
    Oct
  • €344
    Nov
  • €264
    Dec
  • €458
    Jan
  • €306
    Feb
  • €286
    Mar
  • €239
    Apr
  • €295
    May
  • €299
    Jun
  • €201
    Jul
  • €367
    Aug

What is the cheapest day of the week to fly from Seattle Tacoma Intl. Airport to Dulles International Airport?

The data is based on the past 12 months and shows the average ticket prices from Seattle Tacoma Intl. Airport to Dulles International Airport for each day of the week in the Trip.com database.

Based on Trip.com’s data from the past 12 months, the cheapest day to depart from Seattle Tacoma Intl. Airport to Dulles International Airport is Wednesday, with average fares typically lower than other days. You’ll want to avoid flying on Sunday, as ticket prices are usually the highest that day.

€337
€284
€230
€177
    Cheapest
  • €309
    Mon
  • €298
    Tue
  • €230
    Wed
  • €302
    Thu
  • €287
    Fri
  • €330
    Sat
  • €337
    Sun

Which airline offers the cheapest flights from Seattle Tacoma Intl. Airport to Dulles International Airport?

The cheapest airline flying from Seattle Tacoma Intl. Airport to Dulles International Airport is Alaska Airlines (from €122) among 6 carriers operating this route. Based on Trip.com's latest 7-day flight data.

Alaska Airlines
From €122
Delta Air Lines
From €124
Frontier Airlines
From €126
American Airlines
From €129
United Airlines
From €179
Sun Country Airlines
From €211

Find more flights and airlines

What is the flight schedule from Seattle Tacoma Intl. Airport to Dulles International Airport?

Check the schedule for flights from Seattle to Washington D.C. and find the flight that best matches your travel plans.

Flight info.
Departure
Arrival
Weekly Schedule

  1. DL541

    Seattle Tacoma Intl. Airport

    3:55 PM

    SEA

    4h 56m

    11:51 PM

    IAD

    S M T W T F S
    Search

  2. AS366

    Seattle Tacoma Intl. Airport

    3:56 PM

    SEA

    5h 3m

    11:59 PM

    IAD

    S M T W T F S
    Search

  3. AS367

    Seattle Tacoma Intl. Airport

    9:35 PM

    SEA

    5h 5m

    5:40 AM

    IAD

    S - - W T - S
    Search

  4. AA585

    Seattle Tacoma Intl. Airport

    12:25 PM

    SEA

    5h 17m

    Nonstop

    8:42 PM

    CLT

    - - - - - - S
    Search

  5. AA5077

    Charlotte Douglas International Airport

    10:30 PM

    CLT

    1h 28m

    Nonstop

    11:58 PM

    IAD

    S M T W T F -

  6. AA858

    Seattle Tacoma Intl. Airport

    12:56 PM

    SEA

    5h 4m

    Nonstop

    9:00 PM

    CLT

    S M T W T F -
    Search

  7. AA5077

    Charlotte Douglas International Airport

    10:30 PM

    CLT

    1h 28m

    Nonstop

    11:58 PM

    IAD

    S M T W T F -

  8. DL810

    Seattle Tacoma Intl. Airport

    11:05 PM

    SEA

    4h 21m

    Nonstop

    6:26 AM

    DTW

    S M T W T F S
    Search

  9. DL1605

    Detroit Metropolitan Wayne County Airport

    8:40 AM

    DTW

    1h 32m

    Nonstop

    10:12 AM

    IAD

    - M T W T - -

  10. DL652

    Seattle Tacoma Intl. Airport

    11:35 PM

    SEA

    4h 50m

    Nonstop

    7:25 AM

    ATL

    S M T W T F S
    Search

  11. DL1444

    Hartsfield–Jackson Atlanta International Airport

    9:44 AM

    ATL

    1h 46m

    Nonstop

    11:30 AM

    IAD

    S M T W T - S

  12. AA1833

    Seattle Tacoma Intl. Airport

    12:56 PM

    SEA

    5h 4m

    Nonstop

    9:00 PM

    CLT

    S - T W T - S
    Search

  13. AA5154

    Charlotte Douglas International Airport

    11:20 AM

    CLT

    1h 34m

    Nonstop

    12:54 PM

    IAD

    S M T W T F S

  14. AA707

    Seattle Tacoma Intl. Airport

    10:17 AM

    SEA

    4h 10m

    Nonstop

    4:27 PM

    DFW

    S M T W T F S
    Search

  15. AA2254

    Dallas Fort Worth International Airport

    6:50 PM

    DFW

    3h 2m

    Nonstop

    10:52 PM

    IAD

    S M T W - F S

  16. DL567

    Seattle Tacoma Intl. Airport

    9:20 PM

    SEA

    4h 48m

    Nonstop

    5:08 AM

    ATL

    S M T W T F S
    Search

  17. DL1444

    Hartsfield–Jackson Atlanta International Airport

    9:44 AM

    ATL

    1h 46m

    Nonstop

    11:30 AM

    IAD

    S M T W T - S
Find more flights and airlines

About Seattle Tacoma Intl. Airport and Dulles International Airport

Learn about Seattle Tacoma Intl. Airport (SEA) and Dulles International Airport (IAD) — including location, terminals, transportation, and travel tips.

Flight distance 3,705.38 km
Cheapest one-way ticket price €122
Cheapest return ticket price €152

FAQs for Seattle Tacoma Intl. Airport to Dulles International Airport Flights

  • How long is the flight from Seattle Tacoma Intl. Airport to Dulles International Airport?

    Seattle Tacoma Intl. Airport to Dulles International Airport takes about 4 hours 35 minutes on average. Actual flight time may vary depending on route, weather and air traffic.
  • There are around 6 daily flights from Seattle Tacoma Intl. Airport (SEA) to Dulles International Airport (IAD).
  • The earliest flight from Seattle Tacoma Intl. Airport to Dulles International Airport departs at 08:10, and the last departs at 23:14, with about 8 flights per day. Flight times may change, so please check the latest departure and arrival times before you travel.
  • The route from Seattle Tacoma Intl. Airport (SEA) to Dulles International Airport (IAD) is quite popular. Without considering departure times or holidays, tickets cost around €344 in October, the most expensive month to book this route.
  • The earliest flight departs from Seattle Tacoma Intl. Airport (SEA) at 08:00 and arrives in Dulles International Airport (IAD) at 16:09.
  • The latest flight departs from Seattle Tacoma Intl. Airport (SEA) at 21:55 and arrives in Dulles International Airport (IAD) at 05:49.
  • American Airlines is a very popular airline operating an average of 1589 flights per month.
  • One-way flights from Seattle Tacoma Intl. Airport to Dulles International Airport currently start from €122, and round-trip fares start from €152. The current lowest fare is a Alaska Airlines flight departing on Sat, Nov 7; prices may vary depending on availability.
  • Yes. Alaska Airlines, United Airlines and Delta Air Lines operate direct flights from Seattle Tacoma Intl. Airport to Dulles International Airport, with an average flight time of 4 hours 25 minutes, and around 42 weekly flights. Actual flight frequency may vary by season.
  • Based on Trip.com flight data for departures within the next 30 days with at most one stop, the average one-way price from Seattle Tacoma Intl. Airport to Dulles International Airport is €255. Prices may vary depending on the departure date, airline, and availability.
  • Seattle Tacoma Intl. Airport to Dulles International Airport operates around 42 weekly flights, mainly by Alaska Airlines, United Airlines and Delta Air Lines. Actual frequency may vary during holidays and seasonal schedule adjustments.
  • Enter Seattle Tacoma Intl. Airport and Dulles International Airport, select your departure date and number of passengers, then compare flights by price, flight duration, and baggage allowance. Once you've chosen a fare, review the change and refund rules, fill in passenger details, and pay to receive your booking confirmation.

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Note: Prices shown on this page are estimated lowest price and include all taxes and fees found in the last 24 hours.

Book with no extra fees

Prices displayed in this page are all-inclusive prices (incl. taxes, fuel surcharge, civil aviation development fund, etc) with all fees confirmed before payment. Fees for luggage, meals, WLAN, or other additional services are also included as shown in the flight cards.

Real-time pricing updates

Prices, availability, and travel information on this page were updated within last 24 hours—even in real-time. The more popular the route, the more precise the data.

Change & Cancellation Policy

Trip.com displays flight cancellation and change policies for each flight ticket during the booking process, including fees and applicable conditions. Please check the following scenarios:
Voluntary cancellation/change:
To submit a change or cancellation request, go to the flight bookings page, select the option to change or cancel your booking, choose the relevant passengers and segment, and submit a request. Please note that additional charges may apply according to the airline ticket policy.
Cancellation/change due to a flight schedule change:
If the flight has been rescheduled and you would like to change or cancel your ticket, you can submit an involuntary cancellation request. For more details about change and cancellation policies, please check the customer support pages.