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Cheap IAD to SEA Flights

Prices found within past 7 days. Prices and availability subject to change. Additional terms may apply.

Washington to Seattle route information

Origin Airport Washington Dulles Intl.
Destination Airport Seattle - Tacoma Intl.
Airlines Serving Alaska Airlines, American Airlines, Delta, Frontier Airlines, Sun Country Airlines, United
Flight Price $244
Distance 2,299 mi

Cheap IAD to SEA Flights

  • Question : Is there a day that has more departure times to choose from than other days?
    Answer : Sunday has the greatest variety of flight times for Dulles to Seattle with nine. Friday currently offers the fewest number of flight times with only seven options.
  • Question : How long do most people stay in Seattle?
    Answer : Of course, you are not most people, but if you were, you'd stay around one week.
  • Question : Which airline has the least delays from Dulles to Seattle?
    Answer : Booking with Delta Air Lines means you will arrive to Seattle around the time you were supposed to. In fact, this timely airline has a 91% on-time average. It never hurts to be prepared. If you should choose this airline, be sure to track the flight status to stay on top of the departure time.
  • Question : How long does it take to fly from Dulles to Seattle?
    Answer : From IAD to SEA, the fastest flight time is five hours and 50 minutes. Remember, there is a time change of three hours.
  • Question : What is the cheapest day to fly to Seattle?
    Answer : As of May 20th, the best day for deals to Seattle (SEA) is May 29th. It cost $251, which is 45% below the average price to book the same route.
  • Question : How long is the flight from IAD to SEA?
    Answer : United Airlines can get you there in five hours and 50 minutes. So, if you were to leave Dulles at 8:39 AM EDT, you would get to Seattle at 11:29 AM PDT. Giving you enough time to catch up on your television shows before you land (remember, there is a three-hour time difference).
  • Question : Can I change the date of my flight?
    Answer : You sure can adjust your departure date and you may save yourself some money by doing it. The cheapest day to fly in June is Tuesday. You may be thinking you're missing out taking off a day earlier, but we see it as just adding those savings towards a future vacation. A penny saved is a vacation earned.

Mar 19, 2019

Internet did not work on plane. Not good for 5 hour flight

Mar 11, 2019

Flight from IAD to SEA, on descent into SEA, had condensation leaks over the middle seats, row 12, both sides. Dripped most of the way down. I will mention that to Delta.

Feb 8, 2019

Easiest 5.5 hr flight ever

Jan 20, 2019

Captain paid attention to safety of the passengers

Dec 23, 2018

Really, really small seats for such a new plane.

Dec 21, 2018

Very nice flight attendants.

Dec 19, 2018

Couldn’t get seat to recline. Friendly flight attendants helped me

Dec 13, 2018

Great flight, thank you!

Dec 6, 2018

Wifi should be free!

Dec 5, 2018

Great flight with enough leg room