SEA - IAD

Find cheap flights from Seattle to Washington Dulles Airport from $134

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight departing on 9/2. 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.
Round-trip
1 adult
Economy
0 bags
Sat 6/24
Sat 7/1

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Good to know

Low season

January

High season

July

Cheapest flight

$134

Average price round-trip

$444

Good deal round-trip

$398

Good deal one-way

$219
Best time to beat the crowds with an average 42% drop in price.
Most popular time to fly with an average 35% increase in price.
Flight from Seattle to Washington Dulles Airport
(avg. price over the last 2 weeks)
or less
or less

When to book flights from Seattle to Dulles Intl

Estimated round-trip price
Average price per month
Flight prices as travel date approaches

Top tips for finding a cheap flight from SEA to Washington Dulles Airport

  • Looking for a cheap flight? 25% of our users found flights on this route for $219 or less one-way and $398 or less round-trip.
  • The cheapest flight from Seattle to Washington Dulles Airport was found 89 days before departure, on average.
  • Book at least 3 weeks before departure in order to get a below-average price.
  • High season is considered to be June, July and August. The cheapest month to fly is January.
  • Morning departure is around 21% more expensive than an evening flight, on average*.
  • Seattle-Tacoma International Airport (SEA), also called Sea-Tac, is the main airport for the greater Seattle metropolis. It is about 14 miles from downtown Seattle, and Alaska and Delta Airlines use it as a hub. Washington Dulles International Airport (IAD) is the main airport for the Washington DC area, where it is a United Airlines hub, and is located about 42 miles from downtown DC.
  • You could take one of the many non-stop flights from Seattle to Washington Dulles Airport, or you may prefer a flight with one or more stops. For example, Delta flies to IAD with stops in Detroit or New York City, and American Airlines can take you to DC via Chicago and Charlotte.
  • Flights from Washington Dulles Airport to Seattle average about 2,087 lbs. in CO2 emissions per passenger. If you would like to keep that number as low as possible, you could fly Alaska Air’s non-stop service, which ranges from only around 1,216 to 1,461 lbs. in emissions, about 42% to 30% less than the average.
  • You have two public transport options from downtown Seattle to the airport. The Link Light Rail costs about $3 a person, and you can get tickets at the station. The King County Metro Bus also has numerous routes from the city center to the airport for around $3 as well. You can pay the driver in cash, but you need exact change.
  • If you choose to drive and park your car at SEA, there are long-term parking lots at the airport. At the Terminal Direct parking on the 4th floor of the garage, you can walk to the main terminal from this floor for about $42 a day or around $294 a week. You can park on the other floors for around $34 a day or $169 per week.
*Average of the lowest prices shown in KAYAK’s search results for departures within the next 30 days

FAQs for booking Seattle to Washington Dulles Airport flights

Top 4 airlines serving from Seattle to Dulles Intl

Scores according to KAYAK customer reviews
8.3
Alaska AirlinesOverall score based on 29426 reviews
83comfort
85boarding
85overall
79food
79entertainment
88crew
Airline reviews

Free movies / entertainment was amazing Need more options to buy food inflight

Read more about Alaska Airlines

Free movies / entertainment was amazing Need more options to buy food inflight

Pros: "The crew was friendly and made sure we were comfortable at all times. Loved the warm cookie. A nice touch! We were offered coffee immediately on entering the plane. Perfect for a early morning flight."
Cons: "Nothing I can think of."
Pros: "Nice quiet flight"
Cons: "Crew member attitude specifically regarding passengers in the emergency rows"
Pros: "This is always a quick flight. They usually only serve OJ and water, but the time goes by that it doesn’t matter!"
Pros: "Flight crew was nice"
Cons: "They were careless with our suitcases. When we got to Vancouver, we were missing wheels on our suitcases. 2 wheels on my husband's and 1 on mine. It made it horrible to pull the suitcases."
Pros: "Crew was great, the flight was good. Food is good but expensive."
Cons: "Free or inexpensive food options would be nice. I also prefer when the screens are in the back of the seat and I don't have to stream on my phone or pay high prices to use data."
Pros: "Crew were very attentive and hospitable to the crew. I have been flying ASIANA many times and enjoy the flight as well."
Pros: "Crew was friendly"
Cons: "Tray tables very dirty, flight overbooked, hard to find gate agents"
Pros: "Crew is always amazing and friendly on Alaska."
Cons: "There were no movie devices for some reason on the flight"
Pros: "Nothing"
Cons: "What have been nice if I was told that seat availability was nonexistent. I tried checking in each day without any information such as give it up you suck and you’re going to get the worst seed no better how much you try to avoid it…"
Pros: "Crew was super amazing and friendly! Very good service also!"
Cons: "No seat back entertainment.."
Pros: "Boarding process need to be improved. Seat assignment is horrible"
Cons: "It was fabulous as always! Thank you. I love Delta!"
Cons: "We weren't alerted there was a chance of delays. Over two hours late."
Pros: "Great seat easy flight. The food always seem to be the same. I wish they would change it up every once in a while. I've been on this flight 14 times this year and its always exactly the same.."
Cons: "The gate was under construction in Seattle, and it was impossible to hear the gate agents."
Pros: "Crew was very friendly and efficient. Flight was pretty smooth."
Cons: "On time departure would have been nice. 2.5 hours late."
Pros: "Use my built up miles for the SEA-ANC leg of our trip, as to physically price it out as one ticket usually increases the fare by 300-600 u$d depending upon time of year. As it was the tail end of an already long journey (OKA-ICN/ICN-SEA), booked the First Class Cabin. Every mile was worth it."
Cons: "N/A"
Pros: "The crew really kept us updated on the many delays."
Cons: "There were SO many delays and they kept changing. At one point we got on and off the plane."
Cons: "We paid for comfort plus but the seats were no different than main cabin. Comfort plus experience on other legs was much better."
Pros: "I was upgraded to Comfort+ and the seat next to me was left vacant. That was a great flight!"
Pros: "The food and the crew totally good"
Cons: "Maybe the toilets, need to be clean at least once in a flight"
Pros: "The leg room was really great!"
Cons: "Difficult finding room in over head bin for carry on bags."
Pros: "Crew was super nice"
Cons: "Airline to be more user friendly with connecting to free entertainment"
Pros: "Crew was efficient and pleasant making for a good experience."
Cons: "Nothing"
Cons: "Paid for First Class so I could sleep on this red-eye. Wasted my money. Seat was uncomfortable, legroom in my bulkhead seat was horrible. I can sleep anywhere...make that ALMOST anywhere, now."
Cons: "Caught an earlier flight and the entire team made the process seamless."
Cons: "The staff at the Seattle airport were very rude. The AAInflight wifi doesn't work at all. The Starbucks at Seattle had horrible service. I ordered a grande frappuchino and the cashier said it was a grande. When I got it it was a venti and I got charged extra and the woman who gave it to me was very very rude and sounded bored. She had blue hair. There was a woman who worked there who should be fired you couldn't understand a word she said and got the orders wrong."
Pros: "entertainment (movie) selection was good. would nice to have subtitles available"
Cons: "one flight attendant didn't seem very happy, not very nice serving drinks"
Cons: "Our original flight was delayed then cancelled. After assigning to another flight, it was delayed and gate changed about 10 times and was finally cancelled after it was boarded and left gate after 2am due to engine problem. We had to cancel our trip since it was a short trip for a funeral and we had missed it. AA offered no compensation and no apology (not during the whole night of delays and cancels)."
Pros: "The flight got me there"
Cons: "WiFi was too slow to be able to watch anything. Seat small and uncomfortable. Flight attendants not friendly."
Pros: "We arrived nearly on time & without issue."
Cons: "The plane was warm & no cool air was being dispersed in the cabin & because of that it was very dry. Better temperature regulation, climate control is needed to make fir a more comfortable flight."
Pros: "I had really awful sinus pain on the flight and the crew was very helpful and sympathetic"
Cons: "The entertainment system was pretty lame (DirectTV) and of course the now-typical lack of food and beverage items for domestic flights"
Cons: "This was just so awful! I was so disappointed because I have heard good things about United. The seats I paid extra for were ridiculously small, no leg room at all! Then the plug for earbuds was broken, so I was unable to watch movies or listen to music. I am really dreading the trip back!"
Pros: "I like flying Lufthansa for entire trip then changing to united airlines"
Cons: "Particular everything the airline"
Cons: "I missed having the navigation map when traveling such a long distance."
Pros: "Flight was on time. Friendly crew."
Cons: "It turned out that we were on stand by (without anyone telling us until the morning of the flight) and did not know if we were going to fly out. We could not select any seats at check in and only found out our seats a few hours before the flight. It was quite unpleasant and stressful as my husband and I were flying with our two children and faced a real possibility of not being able to sit together or getting bumped off a flight all together. It was a code shared flight between Lufthansa and United and each airline kept sending us to the other to get any answers or help. neither were helpful. It made it for an extremely frustrating experience."
Pros: "The boarding was quick and the flight was on time. The crew was courteous."
Cons: "I selected economy comfort in the kayak app, but when I called about my boarding pass, kayak said they only sell basic economy. What did I buy? UAL only sells a limited selection of overpriced food. There is no music and you have to pay to see the flight map."
Pros: "The boarding and seating happened in a timely fashion, and the crew was courteous. The lunch meal (I had requested Asian vegetarian) wasn't amazing, but not as bad as it could've been."
Cons: "The flight was not with Lufthansa, but it was actually through United, which was extremely confusing as I did my ticket confirmation, seat booking and meal choice through Lufthansa prior to my trip. To find out on the day of the flight that I had to check in and go through United was extremely annoying, as the counters are in different terminals and it was unnecessarily stressful. The flight itself was crammed, with absolutely no leg space, and not even enough space under the seat to stow my backpack (which had fit perfectly on my Brussels Airlines flight to Madrid). I had requested the Asian vegetarian meal, and the snack we got prior to landing was pretty much two slices of cucumber on a small bun (and an apple on the side) - extremely dry and hard to eat. I asked for mayo, but the flight neither had that, nor any other condiments to make the "sandwich" more edible."
Cons: "I was unable to go on the flight because of the extraordinarily high cost of changing a last name from a maiden name to a married name. I was so disappointed by the service."
Cons: "Gate crew didn't help much with seating or connecting flights. Staff almost never smiled, and when boarding the plane instead of a, "hello" or "good morning", there were two attendants staring at their phones. They looked up when I greeted first, but seemed put off a touch. They also switched the seating without telling us ahead of time, so my husband and I had to sit in middle seats, apart from each other on our anniversary trip. Very unhelpful and unfriendly when I inquired to change."

Book cheap flights from Seattle to Washington Dulles Airport

Recent round-trip flight deals

10/24Tue
1 stopUnited Airlines
17h 22mSEA-IAD
10/30Mon
1 stopUnited Airlines
14h 54mIAD-SEA
$275
10/24Tue
2 stopsUnited Airlines
20h 45mSEA-IAD
10/30Mon
1 stopUnited Airlines
21h 59mIAD-SEA
$280
10/24Tue
nonstopUnited Airlines
5h 02mSEA-IAD
10/30Mon
1 stopUnited Airlines
21h 59mIAD-SEA
$287
9/6Wed
nonstopDelta
5h 03mSEA-IAD
9/12Tue
nonstopDelta
5h 47mIAD-SEA
$298
8/24Thu
nonstopDelta
4h 56mSEA-IAD
8/29Tue
nonstopDelta
5h 52mIAD-SEA
$308
8/29Tue
1 stopAmerican Airlines
7h 32mSEA-IAD
9/7Thu
1 stopAmerican Airlines
9h 28mIAD-SEA
$314
9/6Wed
1 stopAmerican Airlines
7h 40mSEA-IAD
9/12Tue
1 stopAmerican Airlines
9h 28mIAD-SEA
$315
8/15Tue
1 stopUnited Airlines
7h 58mSEA-IAD
8/29Tue
1 stopUnited Airlines
8h 43mIAD-SEA
$317
8/17Thu
nonstopDelta
4h 56mSEA-IAD
8/28Mon
nonstopDelta
5h 52mIAD-SEA
$318
8/28Mon
2 stopsAmerican Airlines
9h 33mSEA-IAD
9/7Thu
1 stopAmerican Airlines
9h 28mIAD-SEA
$320
11/3Fri
nonstopUndisclosed Carrier
1h 35mSEA-IAD
11/6Mon
nonstopUndisclosed Carrier
7h 35mIAD-SEA
$321
9/11Mon
1 stopAmerican Airlines
6h 55mSEA-IAD
9/13Wed
1 stopAmerican Airlines
9h 28mIAD-SEA
$324
8/24Thu
1 stopAmerican Airlines
10h 05mSEA-IAD
8/29Tue
1 stopAmerican Airlines
8h 56mIAD-SEA
$325
8/16Wed
1 stopUnited Airlines
7h 58mSEA-IAD
8/22Tue
1 stopUnited Airlines
8h 49mIAD-SEA
$327
8/23Wed
1 stopUnited Airlines
7h 58mSEA-IAD
8/28Mon
nonstopUnited Airlines
5h 46mIAD-SEA
$328
9/16Sat
1 stopAmerican Airlines
7h 40mSEA-IAD
9/20Wed
2 stopsAmerican Airlines
10h 42mIAD-SEA
$330
8/31Thu
nonstopDelta
5h 08mSEA-IAD
9/5Tue
nonstopDelta
5h 54mIAD-SEA
$333
6/13Tue
nonstopUndisclosed Carrier
1h 35mSEA-IAD
6/19Mon
nonstopUndisclosed Carrier
7h 35mIAD-SEA
$338
8/15Tue
nonstopDelta
4h 56mSEA-IAD
8/22Tue
nonstopDelta
5h 52mIAD-SEA
$348
8/24Thu
nonstopDelta
4h 56mSEA-IAD
9/4Mon
nonstopDelta
5h 52mIAD-SEA
$353

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Recent one-way flight deals

9/2Sat
2 stopsMultiple Airlines
26h 12mSEA-IAD
$134
9/6Wed
nonstopDelta
5h 03mSEA-IAD
$149
8/23Wed
1 stopAmerican Airlines
8h 39mSEA-IAD
$157
9/6Wed
1 stopUnited Airlines
10h 55mSEA-IAD
$159
9/27Wed
2 stopsAmerican Airlines
10h 47mSEA-IAD
$163
7/19Wed
nonstopAlaska Airlines
4h 55mSEA-IAD
$168
8/19Sat
nonstopUndisclosed Carrier
1h 35mSEA-IAD
$169
9/14Thu
2 stopsAmerican Airlines
10h 18mSEA-IAD
$173
9/25Mon
3 stopsUndisclosed Carrier
22h 30mSEA-IAD
$175
9/1Fri
1 stopAmerican Airlines
8h 39mSEA-IAD
$177
7/25Tue
3 stopsUndisclosed Carrier
44h 20mSEA-IAD
$179
5/31Wed
2 stopsUnited Airlines
16h 31mSEA-IAD
$183
8/21Mon
3 stopsUndisclosed Carrier
30h 21mSEA-IAD
$185
6/8Thu
2 stopsMultiple Airlines
41h 20mSEA-IAD
$186
8/21Mon
1 stopUnited Airlines
12h 58mSEA-IAD
$188
7/4Tue
1 stopUnited Airlines
8h 03mSEA-IAD
$189
6/11Sun
2 stopsMultiple Airlines
37h 48mSEA-IAD
$190
6/1Thu
2 stopsMultiple Airlines
38h 12mSEA-IAD
$192
9/5Tue
nonstopDelta
5h 03mSEA-IAD
$199
6/7Wed
nonstopDelta
5h 04mSEA-IAD
$209

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Seattle - Washington Dulles Airport Flights

Departure:

Seattle (SEA)United States

Destination:

Washington Dulles Airport (IAD)United States

Return flight deals:

Washington Dulles Airport - Seattle

Cabin classes:

$658
$699
$523
$179

Browse origins: