Cheap flights from Washington, D.C. Dulles Intl Airport to Seattle from $118
This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from Washington, D.C. Dulles Intl Airport to Seattle departing on 4/30. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.
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Alaska Airlines flights from Washington, D.C. Dulles Intl Airport to Seattle
Our best Alaska Airlines deals on Washington, D.C. Dulles Intl Airport to Seattle flight tickets
Frontier flights from Washington, D.C. Dulles Intl Airport to Seattle
Our best Frontier deals on Washington, D.C. Dulles Intl Airport to Seattle flight tickets
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How to get the cheapest flight ticket from Washington, D.C. Dulles Intl Airport to Seattle
Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip
What is the cheapest month to fly to Seattle?
In general, February is the cheapest month to fly from Washington, D.C. Dulles Intl Airport to Seattle. Due to it being the ‘off-season’ during this time, you can expect flight prices to be around $347. If you don’t want to visit Seattle in February, then you should wait until January to fly from Washington, D.C. Dulles Intl Airport, when ticket prices are also cheap, with an average price of $357.
What is the cheapest day to depart on your flight to Seattle?
On average, the least expensive day to fly to Seattle from Washington, D.C. Dulles Intl Airport is on a Tuesday. momondo users have found tickets for Tuesday departures for as low as $449. However, this price may fluctuate depending on the airline, the season, and holidays. On the other hand, Sunday is the most expensive day to depart from Washington, D.C. Dulles Intl Airport because it is more convenient for both business and leisure travelers. As a result, prices tend to be around $572.
What is the cheapest time of day to depart on your flight to Seattle?
Flying to Seattle from Washington, D.C. Dulles Intl Airport in the evening is the least expensive time of day to depart. momondo users have found prices as low as $409 when looking at flights departing in the evening. Flights to Seattle are more costly in the morning, with an average ticket price of $533. Departure times in the morning fall within the peak daily travel times, which is why tickets can be more expensive.
What is the cheapest Washington, D.C. Dulles Intl to Seattle/Tacoma Intl flight route?
Fly from Washington, D.C. Dulles Intl to Seattle/Tacoma Intl for the best Washington, D.C. Dulles Intl - Seattle/Tacoma Intl flight prices
How far in advance should I book a flight to Seattle?
You are more likely to see cheaper flights to Seattle from Washington, D.C. Dulles Intl Airport when booking 6 weeks ahead of your departure date. In general, you can expect to find flights to Seattle for around $418 when searching 6 weeks out.However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Seattle from Washington, D.C. Dulles Intl Airport for as low as $359 on momondo.
What cabin class options are available on Washington, D.C. Dulles Intl to Seattle/Tacoma Intl flights?
There are 4 cabin classes available to choose from on Washington, D.C. Dulles Intl to Seattle/Tacoma Intl flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.
What is the cheapest airline that flies from Washington, D.C. Dulles Intl to Seattle/Tacoma Intl?
Alaska Airlines, Hawaiian Airlines, and Frontier are the most popular carriers operating from Washington, D.C. Dulles Intl to Seattle/Tacoma Intl
What airlines fly to Seattle?
Alaska Airlines, United Airlines and Delta are the top three most popular airlines that fly to Seattle from Washington, D.C. Dulles Intl Airport according to our data. Alaska Airlines is the first choice among our users, with 39% of people opting to fly with this airline when traveling to Seattle. Keep in mind that there are 7 different airlines that fly to Seattle on a routine basis, so you have a few additional options to choose from.
How many flights depart from Washington, D.C. Dulles Intl Airport to Seattle on average per day?
As of April 2025, 16 flights take off from Washington, D.C. Dulles Intl Airport and land in Seattle each day. The most common flight departure time for this route is 7:00AM, with 44% of daily flights taking off at noon.
How many flights depart from Washington, D.C. Dulles Intl Airport to Seattle on average per week?
As of April 2025, there are 113 flights per week flying from Washington, D.C. Dulles Intl Airport to Seattle. The most common day of the week flights depart is Thu, with 19% of flights taking off on this day.
When to book flights from Washington, D.C. Dulles Intl Airport to Seattle
Cheap Washington, D.C. Dulles Intl Airport to Seattle (IAD to SEA) flight deals and tips
Find info about flight duration, direct flights, and airports for your flight from Washington, D.C. Dulles Intl Airport to Seattle
How far is Washington, D.C. Dulles Intl to Seattle/Tacoma Intl by plane?
The distance between Washington, D.C. Dulles Intl and Seattle/Tacoma Intl is about 2299.7 mi. A reasonable flight in good conditions will take 5h 39m.
When did momondo last update prices for flights from Washington, D.C. Dulles Intl Airport to Seattle/Tacoma Intl Airport?
Prices for flights from Washington, D.C. Dulles Intl Airport to Seattle/Tacoma Intl Airport are updated daily.
How many operators does momondo search for flights from Washington, D.C. Dulles Intl Airport to Seattle/Tacoma Intl Airport?
There are 7 operators available for flights from Washington, D.C. Dulles Intl Airport to Seattle/Tacoma Intl Airport as of April 2025.
How old do you have to be to fly from Washington, D.C. Dulles Intl Airport to Seattle/Tacoma Intl Airport?
The minimum age for a child to fly alone is five, but airlines that offer an unaccompanied minor (UNMR) service may have their own age limitations. Flight duration, scheduling, and layovers are among the considerations that may influence age limits. We recommend that you double-check with the airline you are booking with for travel from Washington, D.C. Dulles Intl Airport to Seattle/Tacoma Intl Airport.
What documentation or ID do you need to fly to Seattle/Tacoma Intl Airport?
The travel and health documents required for your trip to Seattle/Tacoma Intl Airport can vary based on your itinerary and personal situation. As a rule, consider having multiple documents such as a national ID card or driver’s license, and a passport valid for six-months after you plan to arrive at Seattle/Tacoma Intl Airport. We always recommend checking with your airline or a trusted third party such as IATA to get advice.
What is the most popular plane model from Washington, D.C. Dulles Intl Airport to Seattle?
Based on momondo bookings for this flight route, the most popular plane model on flight routes from Washington, D.C. Dulles Intl Airport to Seattle is Boeing 737-800 Passenger/BBJ2 (winglets) (19.28% of total bookings). The next most popular plane models are Boeing 737 MAX 9 (17.95%), Boeing 737-900 (17.50%), and Boeing 737-900 Passenger/BBJ3 (winglets) (11.73%).
What is the most popular airline from Washington, D.C. Dulles Intl Airport to Seattle?
Based on momondo bookings for this flight route, the most popular airline on flight routes from Washington, D.C. Dulles Intl Airport to Seattle is Alaska Airlines (39% of total bookings). The next most popular airlines are United Airlines (38%), Delta (20%), and American Airlines (1%).
Best airlines flying from Washington, D.C. Dulles Intl Airport to Seattle
Compare and see reviews for airlines that fly from Washington, D.C. Dulles Intl Airport to Seattle with momondo
| Airline | Rating | Free Cancellation | Price | ||
|---|---|---|---|---|---|
| PriceFrom $143 | Free Cancellation | Rating 7.9 2,347 reviews | |||
| PriceFrom $144 | Free Cancellation | Rating 6.9 349 reviews | |||
| PriceFrom $213 | Free Cancellation | Rating 8.0 7,897 reviews | |||
| PriceFrom $241 | Free Cancellation | Rating 8.0 9,835 reviews | |||
| PriceFrom $283 | Free Cancellation | Rating 7.4 8,619 reviews | |||
| PriceFrom $285 | Free Cancellation | Rating 7.2 10,000 reviews |
Delta Flights From Washington, D.C. Dulles Intl Airport to Seattle
Across 1 Delta flight from Washington, D.C. Dulles Intl Airport to Seattle this week, the average price was $390, with the best Delta deals starting from $213 round-trip. 7,897 users have rated Delta on momondo, with an average score of 8.0/10.
Alaska Airlines Flights From Washington, D.C. Dulles Intl Airport to Seattle
The best Alaska Airlines deal for Washington, D.C. Dulles Intl Airport to Seattle flight tickets found on momondo in the last 72 hours was $241, round-trip. It should be noted that an average Alaska Airlines flight deal for this route in this time was higher, at $428 round-trip. Alaska Airlines operates 5 flights out of Washington, D.C. Dulles Intl Airport into Seattle in an average week, so prices vary by time and availability. 9,833 Alaska Airlines reviews by users on momondo have scored the airline at 8.0/10.
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Why should I use momondo to find a flight deal from Washington, D.C. to Seattle?
We help find the flight that best suits your needs, momondo compares prices from hundreds of airlines and travel agents and helps you filter them to find the best flight from Washington, D.C. to Seattle for you.
Can I find flights from Washington, D.C. to Seattle with flexible booking policies on momondo?
Yes. momondo allows you to filter the results for Washington, D.C. to Seattle flights to just show those with flexible booking policies.
How can momondo help me find flights from Washington, D.C. to Seattle?
momondo offers useful filters to help you find the right flight. Choose specific flight times, airports or even what payment method you prefer. We have numerous options to help you book your ideal flight from Washington, D.C. to Seattle.
I’m not ready to book a flight from Washington, D.C. to Seattle right now. Can momondo alert me if prices change?
Price alerts on flights to Seattle from Washington, D.C. are quick and easy to set up on momondo. Simply perform a search and select the price alert feature. It is as simple as that.