Find cheap flights from Washington Dulles Airport to Seattle/Tacoma Airport

IAD - SEA

Find cheap flights from Washington Dulles Airport to Seattle/Tacoma Airport

Round-trip
Economy
Washington (IAD)
Seattle/Tacoma Intl
Fri 10/2
Fri 10/9
Any month
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Good to know

Low season

January Best time to beat the crowds with an average 26% drop in price.

High season

July Most popular time to fly with an average 20% increase in price.

Average price of a round-trip

$329 (avg. price over the last 2 weeks)

Good deal for a round-trip

$316 or less

When to book flights from Washington Dulles Intl to Seattle/Tacoma Intl

Estimated round-trip price
Average price per month
Flight prices as travel date approaches
-1 day
-2 days

Top tips for finding a cheap flight

  • Looking for a cheap flight? 25% of our users found flights on this route for $201 or less.
  • The cheapest flight from Washington Dulles Airport to Seattle/Tacoma Airport was found 72 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 20% cheaper than an evening flight, on average*.
*Average of the lowest prices shown in KAYAK’s search results for departures within the next 30 days

FAQs for booking Washington Dulles Airport to Seattle/Tacoma Airport flights

Which airlines have a flexible cancellation policy for flights from Washington Dulles Intl to Seattle/Tacoma Intl due to COVID-19?

Which airlines apply social distancing measures on flights from Washington Dulles Intl to Seattle/Tacoma Intl due to COVID-19?

Are there Seattle/Tacoma Airport travel restrictions currently due to Coronavirus?

How long does a flight from Washington Dulles Airport to Seattle/Tacoma Airport take?

How many flights are there between Washington Dulles Airport and Seattle/Tacoma Airport?

Which airlines provide the cheapest flights from Washington Dulles Airport to Seattle/Tacoma Airport?

Do I need a passport to fly between Washington Dulles Airport and Seattle/Tacoma Airport?

Which airlines fly most frequently between Washington Dulles Airport and Seattle/Tacoma Airport?

What’s the cheapest day of the week to fly Washington Dulles Airport to Seattle/Tacoma Airport?

How does KAYAK find such low prices on flights from Washington Dulles Airport to Seattle/Tacoma Airport?

How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Washington Dulles Airport to Seattle/Tacoma Airport?

What is the Hacker Fare option on flights from Washington Dulles Airport to Seattle/Tacoma Airport?

What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Washington Dulles Airport to Seattle/Tacoma Airport?

Top airline flying Washington Dulles Intl to Seattle/Tacoma Intl

Scores according to KAYAK customer reviews

7.9
Delta
Overall score based on 28,662 reviews
8.1
Boarding
7.8
Comfort
8.5
Crew
7.8
Entertainment
7.5
Food
Airline reviews
Read more about Delta

Book cheap flights from Washington Dulles Airport to Seattle/Tacoma Airport

Recent round-trip flight deals

11/17
Tue
1 stop
Multiple Airlines
7h 18m
IAD - SEA
11/21
Sat
nonstop
Multiple Airlines
5h 01m
SEA - IAD
12/9
Wed
1 stop
Delta
8h 10m
IAD - SEA
12/15
Tue
nonstop
Delta
4h 45m
SEA - IAD
11/23
Mon
1 stop
Multiple Airlines
7h 10m
IAD - SEA
12/14
Mon
2 stops
Multiple Airlines
11h 56m
SEA - IAD
11/21
Sat
1 stop
Multiple Airlines
7h 48m
IAD - SEA
12/5
Sat
nonstop
Multiple Airlines
5h 01m
SEA - IAD
11/2
Mon
1 stop
Multiple Airlines
7h 28m
IAD - SEA
11/3
Tue
1 stop
Multiple Airlines
9h 58m
SEA - IAD
11/25
Wed
1 stop
Delta
8h 54m
IAD - SEA
12/2
Wed
1 stop
Delta
6h 37m
SEA - IAD
11/18
Wed
1 stop
Delta
7h 46m
IAD - SEA
11/21
Sat
1 stop
Delta
8h 07m
SEA - IAD
11/22
Sun
1 stop
Multiple Airlines
7h 48m
IAD - SEA
12/5
Sat
nonstop
Multiple Airlines
5h 01m
SEA - IAD
11/1
Sun
2 stops
Multiple Airlines
12h 34m
IAD - SEA
11/9
Mon
1 stop
Multiple Airlines
7h 49m
SEA - IAD
1/6
Wed
nonstop
Delta
6h 00m
IAD - SEA
1/19
Tue
1 stop
Delta
9h 04m
SEA - IAD
10/30
Fri
1 stop
Multiple Airlines
7h 55m
IAD - SEA
11/3
Tue
1 stop
Multiple Airlines
9h 58m
SEA - IAD
10/30
Fri
1 stop
Multiple Airlines
14h 23m
IAD - SEA
11/4
Wed
nonstop
Multiple Airlines
5h 10m
SEA - IAD
11/6
Fri
nonstop
Multiple Airlines
5h 40m
IAD - SEA
11/10
Tue
1 stop
Multiple Airlines
6h 39m
SEA - IAD
10/19
Mon
1 stop
Multiple Airlines
10h 08m
IAD - SEA
11/10
Tue
nonstop
Multiple Airlines
5h 10m
SEA - IAD
12/3
Thu
2 stops
Multiple Airlines
10h 34m
IAD - SEA
12/10
Thu
1 stop
Multiple Airlines
7h 05m
SEA - IAD
10/17
Sat
1 stop
Multiple Airlines
7h 55m
IAD - SEA
10/23
Fri
2 stops
Multiple Airlines
12h 30m
SEA - IAD
11/20
Fri
1 stop
Multiple Airlines
7h 48m
IAD - SEA
12/2
Wed
nonstop
Multiple Airlines
5h 01m
SEA - IAD
10/24
Sat
nonstop
Multiple Airlines
5h 40m
IAD - SEA
11/7
Sat
nonstop
Multiple Airlines
4h 48m
SEA - IAD
11/13
Fri
1 stop
Multiple Airlines
7h 28m
IAD - SEA
11/14
Sat
1 stop
Multiple Airlines
7h 48m
SEA - IAD
12/1
Tue
nonstop
Multiple Airlines
5h 48m
IAD - SEA
12/4
Fri
1 stop
Multiple Airlines
9h 58m
SEA - IAD
Show more results

Recent one-way flight deals

10/20
Tue
1 stop
Major Airline
8h 07m
IAD - SEA
12/16
Wed
nonstop
Delta
6h 02m
IAD - SEA
11/5
Thu
nonstop
Major Airline
5h 40m
IAD - SEA
11/11
Wed
3 stops
Multiple Airlines
21h 06m
IAD - SEA
10/11
Sun
1 stop
Major Airline
8h 07m
IAD - SEA
10/13
Tue
1 stop
Delta
8h 18m
IAD - SEA
10/20
Tue
nonstop
Major Airline
5h 40m
IAD - SEA
10/11
Sun
1 stop
Delta
8h 36m
IAD - SEA
12/18
Fri
nonstop
Delta
6h 02m
IAD - SEA
10/11
Sun
nonstop
Major Airline
5h 40m
IAD - SEA
12/21
Mon
2 stops
Multiple Airlines
15h 21m
IAD - SEA
11/8
Sun
3 stops
Multiple Airlines
43h 31m
IAD - SEA
11/6
Fri
3 stops
Multiple Airlines
45h 36m
IAD - SEA
10/13
Tue
3 stops
Multiple Airlines
47h 54m
IAD - SEA
12/22
Tue
3 stops
Multiple Airlines
33h 10m
IAD - SEA
11/12
Thu
3 stops
Multiple Airlines
27h 06m
IAD - SEA
10/14
Wed
1 stop
Multiple Airlines
8h 53m
IAD - SEA
10/8
Thu
1 stop
Multiple Airlines
8h 53m
IAD - SEA
11/9
Mon
1 stop
Multiple Airlines
9h 27m
IAD - SEA
11/13
Fri
1 stop
Multiple Airlines
9h 27m
IAD - SEA
Show more results
*
Prices are per person and are for e–tickets and include all taxes & fees in USD.

We attempt to get accurate prices, however, prices are not guaranteed.

Here's why:

We’re not the seller.
At KAYAK we don’t set the prices, so it’s not possible for us to guarantee what other companies are selling.

We compile tonnes of data for you
Our service lets you quickly and easily compare results from hundreds of travel sites at once. In this sense, KAYAK is a search engine and we can't guarantee prices we find.

Why aren’t prices accurate 100% of the time?
Prices on airline seats, hotel rooms and car rentals can change frequently. Several people may also be trying to buy the same travel option simultaneously. As a result, you may find, on occasion, that certain prices are no longer available.

If you have more questions or if you have a bad price to report to us,
please send us an and someone from our team will get back to you promptly.

^
The fares displayed include all taxes and fees for economy class travel and were found by the provider in the last 72 hours. Seats are limited and may not be available on all flights and days. Fares are subject to change and may not be available on all flights or dates of travel. Some carriers charge additional fees for extra checked bags. Please check the carriers' sites.
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