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Dulles Intl

$144+ Cheap flights from Seattle (SEA) to Dulles Intl (IAD)

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 4/25. Fares are subject to change and may not be available on all flights or dates of travel.
SEA — IAD
Mar 26 — Apr 21
Wed 3/26
Wed 4/2
1 adult, Economy
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1. Tell us where you want to go
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Cheapflights Tip: The best prices from Seattle/Tacoma Intl to Washington, D.C. Dulles Intl are usually found in February or September, booked 66 days in advance, depart on a Wednesday or Thursday and return on a Tuesday

Cheap flight deals from Seattle to Dulles Intl

Discover tips and strategies to find the most affordable flight options for your journey from Seattle (SEA) to Dulles Intl (IAD). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated March 21, 2025.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$271
(Alaska Airlines)

One-way from

$144
(Hawaiian Airlines)

Popular in

December

Cheapest in

February

Average price

$419

Good round-trip deal

$331 or less

Good one-way deal

$193 or less
Provider with most accurate pricing for Seattle/Tacoma Intl-Washington, D.C. Dulles Intl flight deals.
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Provider most trusted by Cheapflights users for Seattle/Tacoma Intl-Washington, D.C. Dulles Intl flights.
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From Seattle/Tacoma Intl to Washington, D.C. Dulles Intl
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One-way flight from Seattle/Tacoma Intl to Washington, D.C. Dulles Intl
Search Deals
Highest demand for flights based on searches. 4% potential increase in price ($17 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 2% potential price decrease ($10 potential savings vs. average RT price).
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Average for round-trip flights in March 2025
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Price to beat on a round-trip flight from Seattle/Tacoma Intl to Washington, D.C. Dulles Intl.
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Price to beat on a one-way flight from Seattle/Tacoma Intl to Washington, D.C. Dulles Intl.
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Find flight deals from Seattle to Dulles Intl

Cheapest flights from Seattle to Dulles Intl
Explore the most affordable flight options available from Seattle to Dulles Intl. Find the lowest fares from popular airlines and budget airlines, with prices last updated on March 21, 2025.

This Alaska Airlines deal was found by Cheapflights users on 3/21. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/2211:40 pmSEA - IAD
Nonstop5h 03mAlaska Airlines
Wed 4/2310:00 amIAD - SEA
Nonstop5h 40mAlaska Airlines
Deal found 3/21$271
This CheapTickets deal was found by Cheapflights users on 3/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapTickets is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/2211:40 pmSEA - IAD
Nonstop5h 03mHawaiian Airlines
Tue 4/297:13 pmIAD - SEA
Nonstop5h 47mHawaiian Airlines
Deal found 3/19$272
This United Airlines deal was found by Cheapflights users on 3/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/178:15 amSEA - IAD
Nonstop5h 07mUnited Airlines
Tue 4/225:30 pmIAD - SEA
Nonstop5h 51mUnited Airlines
Deal found 3/20$282
This Sun Country Air deal was found by Cheapflights users on 3/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Sun Country Air is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/176:33 pmSEA - IAD
1 stop13h 50mSun Country Air
Thu 4/2412:37 pmIAD - SEA
1 stop24h 55mSun Country Air
Deal found 3/20$295
This Delta deal was found by Cheapflights users on 3/21. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 4/1210:15 pmSEA - IAD
Nonstop4h 53mDelta
Thu 4/177:25 amIAD - SEA
Nonstop5h 55mDelta
Deal found 3/21$297
This Trip.com deal was found by Cheapflights users on 3/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/1711:50 pmSEA - IAD
1 stop8h 33mMultiple Airlines
Thu 4/2410:00 amIAD - SEA
Nonstop5h 40mMultiple Airlines
Deal found 3/20$298
This Southwest deal was found by Cheapflights users on 3/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/157:10 amSEA - IAD
2 stops12h 25mSouthwest
Wed 4/162:50 pmIAD - SEA
1 stop11h 40mSouthwest
Deal found 3/20$308
This American Airlines deal was found by Cheapflights users on 3/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 6/249:50 pmSEA - IAD
1 stop7h 50mAmerican Airlines
Fri 7/45:41 pmIAD - SEA
1 stop8h 14mAmerican Airlines
Deal found 3/20$322
This Gotogate deal was found by Cheapflights users on 3/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Gotogate is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 5/48:22 pmSEA - IAD
1 stop31h 09mFrontier
Sun 5/118:01 amIAD - SEA
1 stop12h 59mFrontier
Deal found 3/20$370

Cheapflights Fare Finder

Customize your flight search to find flights from Seattle to Dulles Intl that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated March 21, 2025.
Use the filters below to find and compare flights from Seattle to Washington, D.C. Dulles Intl Airport that are best for you.

Fly from

Seattle

Fly to

Dulles Intl

Route

Depart

Return

Price

SeattleWashington, D.C.

SEA - IAD

SEAIAD

Seattle/Tacoma Intl

Tue 4/22

11:40 pm-7:43 am

Nonstop5h 03m

Washington, D.C. Dulles Intl

Wed 4/23

10:00 am-12:40 pm

Nonstop5h 40m

$271

SeattleWashington, D.C.

SEA - IAD

SEAIAD

Seattle/Tacoma Intl

Tue 4/22

11:40 pm-7:43 am

Nonstop5h 03m

Washington, D.C. Dulles Intl

Tue 4/29

7:13 pm-10:00 pm

Nonstop5h 47m

$272

SeattleWashington, D.C.

SEA - IAD

SEAIAD

Seattle/Tacoma Intl

Thu 4/17

8:15 am-4:22 pm

Nonstop5h 07m

Washington, D.C. Dulles Intl

Tue 4/22

5:30 pm-8:21 pm

Nonstop5h 51m

$282

SeattleWashington, D.C.

SEA - IAD

SEAIAD

Seattle/Tacoma Intl

Thu 4/17

6:33 pm-11:23 am

1 stop13h 50m

Washington, D.C. Dulles Intl

Thu 4/24

12:37 pm-10:32 am

1 stop24h 55m

$295

SeattleWashington, D.C.

SEA - IAD

SEAIAD

Seattle/Tacoma Intl

Sat 4/12

10:15 pm-6:08 am

Nonstop4h 53m

Washington, D.C. Dulles Intl

Thu 4/17

7:25 am-10:20 am

Nonstop5h 55m

$297

SeattleWashington, D.C.

SEA - IAD

SEAIAD

Seattle/Tacoma Intl

Thu 4/17

11:50 pm-11:23 am

1 stop8h 33m

Washington, D.C. Dulles Intl

Thu 4/24

10:00 am-12:40 pm

Nonstop5h 40m

$298

SeattleWashington, D.C.

SEA - IAD

SEAIAD

Seattle/Tacoma Intl

Tue 4/15

7:10 am-10:35 pm

2 stops12h 25m

Washington, D.C. Dulles Intl

Wed 4/16

2:50 pm-11:30 pm

1 stop11h 40m

$308

SeattleWashington, D.C.

SEA - IAD

SEAIAD

Seattle/Tacoma Intl

Tue 6/24

9:50 pm-8:40 am

1 stop7h 50m

Washington, D.C. Dulles Intl

Fri 7/4

5:41 pm-10:55 pm

1 stop8h 14m

$322

SeattleWashington, D.C.

SEA - IAD

SEAIAD

Seattle/Tacoma Intl

Sun 5/4

8:22 pm-6:31 am

1 stop31h 09m

Washington, D.C. Dulles Intl

Sun 5/11

8:01 am-6:00 pm

1 stop12h 59m

$370

SeattleWashington, D.C.

SEA - IAD

SEAIAD

Seattle/Tacoma Intl

Fri 4/25

11:40 pm-7:43 am

Nonstop5h 03m

$144

Flights are sorted by cheapest round-trip flights first.

Deals found on 3/21

Showing 1-10 of 18 results
1
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Compare providers for flights from Seattle to Dulles Intl

Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.
Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from Seattle to Dulles Intl in March.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy1 starTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*3 stars
eDreamsPrice Accuracy3 starsTrust Score*3 stars
CheapfaremartPrice Accuracy-Trust Score*3 stars
Kiwi.comPrice Accuracy3 starsTrust Score*2 stars
CheapflightsfaresPrice Accuracy3 starsTrust Score*2 stars
PricelinePrice Accuracy1 starTrust Score*3 stars
CheapTicketsDealPrice Accuracy3 starsTrust Score*3 stars

*The Trust Score is based on feedback from users after their booking experience. It measures overall satisfaction, helping us identify issues like hidden fees, problems during the ticketing process, and the quality of customer service. This score is our best indicator of the provider's quality and reliability.

  • Most accurate provider: When it comes to deals on Seattle-Washington, D.C. Dulles Intl Airport flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Seattle-Washington, D.C. Dulles Intl Airport flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Seattle-Washington, D.C. Dulles Intl Airport flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Seattle-Washington, D.C. Dulles Intl Airport flights, Cheapflights users trust FlightHub the most. FlightHub has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for Seattle-Washington, D.C. Dulles Intl Airport flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

The best insider tips for Seattle to Washington, D.C. Dulles Intl Airport flights

Snippets provided in this section are AI-generated based on a summarization of Cheapflights-commissioned articles. The articles are presented as-is, for general informational purposes only, and may not be up-to-date. The opinions contained in the articles are original to the author and reflect their authentic experience, which may vary significantly from the experience of others.
Cheapflights partnered with top experts to bring you the best recommendations for your Seattle to Washington, D.C. Dulles Intl Airport trip
Airlines
Alaska Airlines

Saver Fare allows a carry-on bag, unlike many basic economy options.


Alaska Lounge offers fresh seasonal food and craft cocktails, surpassing many competitors.

Read more about Alaska Airlinesby Robert Schrader
United Airlines

Basic Economy allows a personal item only, no carry-on bags unless exceptions apply.


Polaris Business Class offers lie-flat seats and access to exclusive Polaris Lounges.

Read more about United Airlinesby Harriet Baskas
Airports
SEA

Use SEA Spot Saver to book security screening appointments in advance, reducing wait times for non-expedited passengers.

Read more about SEAby Brandon Schultz
IAD

Take the Silver Line Metro from IAD to downtown D.C. in under 40 minutes for a cost-effective travel option.

Read more about IADby Ramsey Qubein
Our travel experts
Robert Schrader

Robert Schrader

Expert on Alaska Airlines

Robert Schrader

Robert Schrader

One of the web's original travel bloggers, Robert launched his first site Leave Your Daily Hell in 2009. Since then, he's expanded into destination niche sites (one each for Japan, Thailand and Taiwan), in addition to having written for the inflight magazines of Singapore Airlines and Korean Air. Overall, he's visited nearly 100 countries, and flies business as often as possible.

Read more
Harriet Baskas

Harriet Baskas

Expert on United Airlines

Harriet Baskas

Harriet Baskas

Harriet is an award-winning journalist who is happiest in an airport or an unusual museum. Her stories about airports, air travel, and the business of travel have appeared on NBC News, CNBC, USA TODAY, The Points Guy and other outlets. She is the creator of the StuckatTheAirport.com blog and the author of nine books. When not out on the road or exploring the latest airport amenities, she’s home in Seattle getting ready for the next adventure.

Read more
Ramsey Qubein

Ramsey Qubein

Expert on IAD

Ramsey Qubein

Ramsey Qubein

An avid traveler and aviation expert who has visited 173 countries, all 50 states and seven continents, Ramsey Qubein flies nearly 400,000 miles a year. As a North Carolina-based freelance journalist for publications including Conde Nast Traveler, Forbes, USA Today and Bloomberg among others, he explores the latest trends in aviation, hospitality, cruises and business.

Read more
Brandon Schultz

Brandon Schultz

Expert on SEA

Brandon Schultz

Brandon Schultz

Brandon Schultz is an award-winning food and travel writer based in New York City. His work has appeared in Forbes, AAA, Thrillist, Travel + Leisure, and The Daily Meal, among many others, and he is the author of 6 books, including 3 cookbooks.

Read more

Best time to book a flight from Seattle to Dulles Intl

Have a flexible travel schedule? Discover the best time to fly to Dulles Intl from Seattle with our price prediction graph.
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Cheapflights Insights

Everything you need to know about your flight from Seattle to Washington, D.C. Dulles Intl Airport

How far ahead should I book a flight from Seattle to Washington, D.C. Dulles Intl Airport?

Use this chart to determine the optimal time to book a round-trip flight from Seattle to Dulles Intl. Price data was last updated on March 14, 2025.

Booking 35 days in advance of your planned departure date is, on average, the best time to get cheap flights from Seattle to Washington, D.C. Dulles Intl Airport. The general trend is that the closer you book to the departure date, the more expensive your flight will be.

What is the cheapest month to book a flight from Seattle to Washington, D.C. Dulles Intl Airport?

Currently, August is the cheapest month in which you can book a flight from Seattle to Washington, D.C. Dulles Intl Airport (average of $309). Flying from Seattle to Washington, D.C. Dulles Intl Airport in June is currently the most expensive (average of $387). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

What is the cheapest time of day to fly from SEA to IAD?

Find hourly flight availability from Seattle to Dulles Intl. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated March 21, 2025.

A simple way to save on the total cost of your ticket is to fly from Seattle to Washington, D.C. Dulles Intl Airport in the afternoon. If you’re flexible enough to do this you can expect to save up to 39% on your trip compared to booking a flight at noon.

What is the cheapest day to fly from Seattle to Washington, D.C. Dulles Intl Airport?

Use this chart to determine the cheapest time to fly round-trip from Seattle to Dulles Intl. Price data was last updated on March 16, 2025.

Travelers seeking maximum savings on their Seattle to Washington, D.C. Dulles Intl Airport flight should consider departing on Saturday afternoons when fares are most often at their lowest. Sunday at noon flights should be avoided if possible as fares are typically the most expensive at this time.

Weekly flight availability from Seattle to Washington, D.C. Dulles Intl Airport

Explore weekly flight availability from Seattle to Dulles Intl. Discover flights operating on different days of the week, giving you the flexibility to choose a travel day that best fits your plans. Compare info to find the most convenient option for your journey. Data last updated March 21, 2025.

The most flights from SEA to IAD are scheduled on a Friday (19 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (8 on average).

Rainfall in Dulles Intl by month

Plan your trip to Dulles Intl by taking into account the average rainfall totals by month.

In terms of precipitation, rainfall in Washington, D.C. Dulles Intl Airport ranges from 2.6 - 4.0 inches per month. May is typically the wettest month, when rainfall can reach 4.0 in. February is typically the driest time to visit Washington, D.C. Dulles Intl Airport when rainfall is around 2.6 in.

Temperature in Dulles Intl by month

Plan your trip to Dulles Intl by taking into account the average temperature totals by month.

If weather is an important factor for your trip to Washington, D.C. Dulles Intl Airport, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 80.6 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 35.6 F).

Reviews of airlines servicing Dulles Intl

Get insights into the airlines that provide service to Dulles Intl. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Dulles Intl. Reviews last updated March 21, 2025.
Get a feel of what it's like to fly with Southwest, Alaska Airlines and Delta from Seattle to Washington, D.C. by reading reviews from past customers. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.
Southwest
8.1
Very good
4,281 reviews

Boarding

8.2

Entertainment

7.6

Comfort

8.1

Overall

8.1

Crew

8.7

Food

7.1

Reviews

1 / 20
8.0
Excellent

Ila,Mar 2025

HOU - DAL

Our original flight was delayed. We were able to change our flight and got home at close to the same time. Looking forward to when you have assigned seating.
Southwest
8.1
Very good
4,281 reviews
Southwest
8.1
Very good
4,281 reviews

Boarding

8.2

Entertainment

7.6

Comfort

8.1

Overall

8.1

Crew

8.7

Food

7.1

Reviews

1 / 20
8.0
Excellent

Ila,Mar 2025

HOU - DAL

Our original flight was delayed. We were able to change our flight and got home at close to the same time. Looking forward to when you have assigned seating.
Alaska Airlines
8.0
Very good
9,759 reviews
Southwest
8.1
Very good
4,281 reviews

Boarding

8.2

Entertainment

7.6

Comfort

8.1

Overall

8.1

Crew

8.7

Food

7.1

Reviews

1 / 20
8.0
Excellent

Ila,Mar 2025

HOU - DAL

Our original flight was delayed. We were able to change our flight and got home at close to the same time. Looking forward to when you have assigned seating.
Delta
8.0
Very good
7,895 reviews
Southwest
8.1
Very good
4,281 reviews

Boarding

8.2

Entertainment

7.6

Comfort

8.1

Overall

8.1

Crew

8.7

Food

7.1

Reviews

1 / 20
8.0
Excellent

Ila,Mar 2025

HOU - DAL

Our original flight was delayed. We were able to change our flight and got home at close to the same time. Looking forward to when you have assigned seating.
Hawaiian Airlines
7.9
Good
2,325 reviews
Southwest
8.1
Very good
4,281 reviews

Boarding

8.2

Entertainment

7.6

Comfort

8.1

Overall

8.1

Crew

8.7

Food

7.1

Reviews

1 / 20
8.0
Excellent

Ila,Mar 2025

HOU - DAL

Our original flight was delayed. We were able to change our flight and got home at close to the same time. Looking forward to when you have assigned seating.
United Airlines
7.4
Good
8,605 reviews
Southwest
8.1
Very good
4,281 reviews

Boarding

8.2

Entertainment

7.6

Comfort

8.1

Overall

8.1

Crew

8.7

Food

7.1

Reviews

1 / 20
8.0
Excellent

Ila,Mar 2025

HOU - DAL

Our original flight was delayed. We were able to change our flight and got home at close to the same time. Looking forward to when you have assigned seating.

Related info for your journey

Find useful and relevant information for your journey from Seattle to Dulles Intl. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • What airport do you fly from for flights from Seattle to Washington, D.C. Dulles Intl?

    If you book a flight to Washington, D.C. Dulles Intl from Seattle, you will be flying from Seattle/Tacoma Intl, which is the city’s only airport. Seattle/Tacoma Intl (SEA) is located 11.4 mi from the center of Seattle. There are 15 flights from Seattle/Tacoma Intl to Washington, D.C. Dulles Intl per day from 6 different airlines.

  • What are the cheapest airlines flying from Seattle to Washington, D.C. Dulles Intl Airport round-trip?

    Alaska Airlines, at $271, was found to be the cheapest airline from Seattle to Washington, D.C. Dulles Intl Airport.Alternate airlines to your destination round-trip include Hawaiian Airlines and Sun Country Air. Alaska Airlines is 33% cheaper than the average price of flights available within the next 90 days to this destination.

  • What are the cheapest airlines to fly from Seattle to Washington, D.C. Dulles Intl Airport one-way?

    The cheapest airlines for a one-way flight from Seattle to Washington, D.C. Dulles Intl Airport are Hawaiian Airlines ($144), Sun Country Air ($145), and American Airlines ($149).

  • What are the most reliable airlines from Seattle to Washington, D.C. Dulles Intl Airport?

    Looking for the most reliable airlines to get you to your destination on time? Our data shows these are most likely to get you from Seattle to Washington, D.C. Dulles Intl Airport on time: Korean Air (100%), Avianca (96%), Ethiopian Air (93%).

  • What are the cheapest flights from Seattle to Washington, D.C. Dulles Intl Airport?

    Looking at all options, your cheapest flight can be booked for $143. While the most popular route (Seattle/Tacoma Intl - Washington, D.C. Dulles Intl) can be booked for $271 on average our data indicates $1,275 when flying from Seattle to Washington, D.C. Dulles Intl Airport.

  • Can I find deals for flights from Seattle to Dulles Intl that include hotel bookings?

    Yes. In addition to deals on Seattle to Dulles Intl flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Seattle to Dulles Intl?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Seattle to Dulles Intl.

  • Can I find deals for business class flights from Seattle to Dulles Intl?

    Yes. Cheapflights offers flight deals from Seattle to Dulles Intl by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

  • What is the cheapest month to book a flight from Seattle to Washington, D.C. Dulles Intl Airport?

    Currently, August is the cheapest month in which you can book a flight from Seattle to Washington, D.C. Dulles Intl Airport (average of $309). Flying from Seattle to Washington, D.C. Dulles Intl Airport in June is currently the most expensive (average of $387). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

See more FAQs

Traveling to a place near Seattle?

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Alternative routes for Seattle to Dulles Intl

See prices for flight routes from nearby airports that may be better suited for you.
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Top 6 airlines flying from Seattle to Dulles Intl

Discover the top 6 airlines that operate flights from Seattle to Dulles Intl. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated March 21, 2025.
AirlineCheapestAverageFlexibilityOn-time
Hawaiian AirlinesCheapest$143Average$332FlexibilityNo cancel feeOn-time85%
Sun Country AirCheapest$169Average$534FlexibilityNo cancel feeOn-time83%
DeltaCheapest$195Average$397FlexibilityNo cancel feeOn-timeN/A
Alaska AirlinesCheapest$239Average$433FlexibilityNo cancel feeOn-time75%
United AirlinesCheapest$245Average$453FlexibilityNo cancel feeOn-time69%
American AirlinesCheapest$256Average$531FlexibilityNo cancel feeOn-time71%
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