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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 4/27. Fares are subject to change and may not be available on all flights or dates of travel.
SEA — IAD
Mar 19 — Mar 261
Wed 3/19
Wed 3/26
1 adult, Economy
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1. Tell us where you want to go
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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 14, 2025.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$249
(Expedia)

One-way from

$144
(Delta)

Popular in

December

Cheapest in

February

Average price

$417

Good round-trip deal

$348 or less

Good one-way deal

$188 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
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Highest demand for flights based on searches. 4% potential increase in price ($16 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 14, 2025.

This Expedia deal was found by Cheapflights users on 3/11. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/294:00 pmSEA - IAD
Nonstop4h 58mMultiple Airlines
Fri 5/28:01 amIAD - SEA
1 stop12h 59mMultiple Airlines
Deal found 3/11$249
This CheapOair deal was found by Cheapflights users on 3/12. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/96:50 pmSEA - IAD
1 stop8h 41mFrontier
Mon 5/128:01 amIAD - SEA
1 stop12h 59mFrontier
Deal found 3/12$255
This SmartFares deal was found by Cheapflights users on 3/12. 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 SmartFares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 4/2612:36 pmSEA - IAD
Nonstop5h 07mAlaska Airlines
Sat 5/36:30 amIAD - SEA
Nonstop5h 43mAlaska Airlines
Deal found 3/12$262
This Trip.com deal was found by Cheapflights users on 3/12. 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.
Tue 4/2211:40 pmSEA - IAD
Nonstop5h 03mHawaiian Airlines
Tue 4/296:30 amIAD - SEA
Nonstop5h 43mHawaiian Airlines
Deal found 3/12$273
This Delta deal was found by Cheapflights users on 3/13. 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
Sat 4/197:25 amIAD - SEA
Nonstop5h 55mDelta
Deal found 3/13$278
This American Airlines deal was found by Cheapflights users on 3/12. 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.
Sat 4/265:22 amSEA - IAD
1 stop8h 01mAmerican Airlines
Sat 5/35:13 pmIAD - SEA
1 stop8h 56mAmerican Airlines
Deal found 3/12$295
This United Airlines deal was found by Cheapflights users on 3/12. 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.
Fri 5/212:40 pmSEA - IAD
1 stop7h 32mUnited Airlines
Tue 5/64:00 pmIAD - SEA
1 stop9h 50mUnited Airlines
Deal found 3/12$302
This Booking.com deal was found by Cheapflights users on 3/13. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/246:25 pmSEA - IAD
1 stop14h 58mSun Country Air
Sun 4/2712:17 pmIAD - SEA
1 stop7h 55mSun Country Air
Deal found 3/13$340
This Southwest deal was found by Cheapflights users on 3/11. 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 4/16:40 amSEA - IAD
2 stops13h 45mSouthwest
Fri 4/45:30 pmIAD - SEA
1 stop10h 00mSouthwest
Deal found 3/11$363

Find flights from Seattle to Dulles Intl within your budget

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 14, 2025.

Fly from

Seattle

Fly to

Dulles Intl

Route

Depart

Return

Price

SeattleWashington, D.C.

SEA - IAD

SEAIAD

Seattle/Tacoma Intl

Tue 4/29

4:00 pm-11:58 pm

Nonstop4h 58m

Washington, D.C. Dulles Intl

Fri 5/2

8:01 am-6:00 pm

1 stop12h 59m

$249

SeattleWashington, D.C.

SEA - IAD

SEAIAD

Seattle/Tacoma Intl

Fri 5/9

6:50 pm-6:31 am

1 stop8h 41m

Washington, D.C. Dulles Intl

Mon 5/12

8:01 am-6:00 pm

1 stop12h 59m

$255

SeattleWashington, D.C.

SEA - IAD

SEAIAD

Seattle/Tacoma Intl

Sat 4/26

12:36 pm-8:43 pm

Nonstop5h 07m

Washington, D.C. Dulles Intl

Sat 5/3

6:30 am-9:13 am

Nonstop5h 43m

$262

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

6:30 am-9:13 am

Nonstop5h 43m

$273

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

Sat 4/19

7:25 am-10:20 am

Nonstop5h 55m

$278

SeattleWashington, D.C.

SEA - IAD

SEAIAD

Seattle/Tacoma Intl

Sat 4/26

5:22 am-4:23 pm

1 stop8h 01m

Washington, D.C. Dulles Intl

Sat 5/3

5:13 pm-11:09 pm

1 stop8h 56m

$295

SeattleWashington, D.C.

SEA - IAD

SEAIAD

Seattle/Tacoma Intl

Fri 5/2

12:40 pm-11:12 pm

1 stop7h 32m

Washington, D.C. Dulles Intl

Tue 5/6

4:00 pm-10:50 pm

1 stop9h 50m

$302

SeattleWashington, D.C.

SEA - IAD

SEAIAD

Seattle/Tacoma Intl

Thu 4/24

6:25 pm-12:23 pm

1 stop14h 58m

Washington, D.C. Dulles Intl

Sun 4/27

12:17 pm-5:12 pm

1 stop7h 55m

$340

SeattleWashington, D.C.

SEA - IAD

SEAIAD

Seattle/Tacoma Intl

Tue 4/1

6:40 am-11:25 pm

2 stops13h 45m

Washington, D.C. Dulles Intl

Fri 4/4

5:30 pm-12:30 am

1 stop10h 00m

$363

SeattleWashington, D.C.

SEA - IAD

SEAIAD

Seattle/Tacoma Intl

Thu 4/10

10:15 pm-6:08 am

Nonstop4h 53m

$144

Flights are sorted by cheapest round-trip flights first.

Deals found on 3/13

Showing 1-10 of 18 results
1
2

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
CheapTicketsDealPrice Accuracy3 starsTrust Score*3 stars
PricelinePrice Accuracy1 starTrust 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

Find out what our experts recommend to make the most of 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

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.

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.

Travel insights for flights from Seattle to Dulles Intl

Get recent, data-driven insights about flights from Seattle to Dulles Intl including ideal travel times, pricing trends, and more.

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 7, 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 $388). 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 14, 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 37% 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 9, 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 14, 2025.

The most flights from SEA to IAD are scheduled on a Thursday (20 on average). You will have fewer flight options on Tuesday, which is when the least amount of flights are scheduled (7 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 14, 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
4,292 reviews

Overall

8.1

Comfort

8.1

Entertainment

7.6

Boarding

8.2

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
4,292 reviews
Southwest
8.1
Very good
4,292 reviews

Overall

8.1

Comfort

8.1

Entertainment

7.6

Boarding

8.2

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
9,734 reviews
Southwest
8.1
Very good
4,292 reviews

Overall

8.1

Comfort

8.1

Entertainment

7.6

Boarding

8.2

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
7,944 reviews
Southwest
8.1
Very good
4,292 reviews

Overall

8.1

Comfort

8.1

Entertainment

7.6

Boarding

8.2

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
2,318 reviews
Southwest
8.1
Very good
4,292 reviews

Overall

8.1

Comfort

8.1

Entertainment

7.6

Boarding

8.2

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
8,623 reviews
Southwest
8.1
Very good
4,292 reviews

Overall

8.1

Comfort

8.1

Entertainment

7.6

Boarding

8.2

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 13 flights from Seattle/Tacoma Intl to Washington, D.C. Dulles Intl per day from 5 different airlines.

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

    Frontier, at $255, was found to be the cheapest airline from Seattle to Washington, D.C. Dulles Intl Airport.Alternate airlines to your destination round-trip include Alaska Airlines and Hawaiian Airlines. Frontier is 37% 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 Delta ($144), Sun Country Air ($145), and Alaska Airlines ($148).

  • 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: Avianca (87%), Brussels Airlines (87%), Ethiopian Air (85%).

  • 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 $232 on average our data indicates $1,227 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 $388). 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

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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.
Seattle to Reagan-National flights
Seattle to Baltimore flights
Portland to Dulles Intl flights
Portland to Reagan-National flights
Portland to Baltimore flights
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Spokane to Reagan-National flights
Spokane to Baltimore flights
Pasco to Dulles Intl flights
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Wenatchee to Dulles Intl flights
Pullman to Baltimore flights
Yakima to Baltimore flights
Wenatchee to Baltimore flights
Bellingham to Reagan-National flights
Walla Walla to Dulles Intl flights
Yakima to Reagan-National flights
Bellingham to Dulles Intl flights
Walla Walla to Baltimore flights
Walla Walla to Reagan-National flights

Top 5 airlines flying from Seattle to Dulles Intl

Discover the top 5 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 14, 2025.
AirlineCheapestAverageFlexibilityOn-time
Sun Country AirCheapest$169Average$534FlexibilityNo cancel feeOn-time83%
DeltaCheapest$196Average$405FlexibilityNo cancel feeOn-timeN/A
Alaska AirlinesCheapest$236Average$434FlexibilityNo cancel feeOn-time75%
United AirlinesCheapest$248Average$448FlexibilityNo cancel feeOn-time69%
American AirlinesCheapest$336Average$531FlexibilityNo cancel feeOn-time71%
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