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CA $275 Cheap Flights from Seattle (SEA) to Washington (IAD)

View CA $275 flight on Thu, Jan 21, 2027Opens in a new window

Popular airlines from Seattle-Tacoma International Airport (SEA) to Washington Dulles International Airport (IAD)

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Cheap flights from Seattle (SEA) to Washington (IAD)

Prices were available within the past 7 days and start at CA $275 for one-way flights and CA $520 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Alaska Airlines
Sat, Oct 24 - Sat, Oct 31
SEA
Seattle
IAD
Washington
CA $520 Roundtrip, found 1 hour ago
CA $520
Roundtrip
found 1 hour ago
Select Alaska Airlines flight, departing Sat, Oct 24 from Seattle to Washington, returning Sat, Oct 31, priced at CA $520 found 1 hour ago
Delta
Wed, Nov 4 - Sun, Nov 8
SEA
Seattle
IAD
Washington
CA $523 Roundtrip, found 7 hours ago
CA $523
Roundtrip
found 7 hours ago
Select Delta flight, departing Wed, Nov 4 from Seattle to Washington, returning Sun, Nov 8, priced at CA $523 found 7 hours ago
Alaska Airlines
Wed, Nov 4 - Tue, Nov 10
SEA
Seattle
IAD
Washington
CA $524 Roundtrip, found 1 day ago
CA $524
Roundtrip
found 1 day ago
Select Alaska Airlines flight, departing Wed, Nov 4 from Seattle to Washington, returning Tue, Nov 10, priced at CA $524 found 1 day ago
Alaska Airlines
Wed, Dec 2 - Sat, Dec 5
SEA
Seattle
IAD
Washington
CA $536 Roundtrip, found 12 hours ago
CA $536
Roundtrip
found 12 hours ago
Select Alaska Airlines flight, departing Wed, Dec 2 from Seattle to Washington, returning Sat, Dec 5, priced at CA $536 found 12 hours ago
Alaska Airlines
Fri, Dec 4 - Tue, Dec 8
SEA
Seattle
IAD
Washington
CA $537 Roundtrip, found 1 day ago
CA $537
Roundtrip
found 1 day ago
Select Alaska Airlines flight, departing Fri, Dec 4 from Seattle to Washington, returning Tue, Dec 8, priced at CA $537 found 1 day ago
American Airlines
Sat, Nov 7 - Wed, Nov 11
SEA
Seattle
IAD
Washington
CA $550 Roundtrip, found 7 hours ago
CA $550
Roundtrip
found 7 hours ago
Select American Airlines flight, departing Sat, Nov 7 from Seattle to Washington, returning Wed, Nov 11, priced at CA $550 found 7 hours ago
American Airlines
Wed, Nov 4 - Tue, Nov 10
SEA
Seattle
IAD
Washington
CA $551 Roundtrip, found 1 day ago
CA $551
Roundtrip
found 1 day ago
Select American Airlines flight, departing Wed, Nov 4 from Seattle to Washington, returning Tue, Nov 10, priced at CA $551 found 1 day ago
American Airlines
Thu, Sep 24 - Wed, Sep 30
SEA
Seattle
IAD
Washington
CA $554 Roundtrip, found 4 days ago
CA $554
Roundtrip
found 4 days ago
Select American Airlines flight, departing Thu, Sep 24 from Seattle to Washington, returning Wed, Sep 30, priced at CA $554 found 4 days ago
Sun Country Airlines
Thu, Oct 15 - Mon, Oct 19
SEA
Seattle
IAD
Washington
CA $595 Roundtrip, found 1 day ago
CA $595
Roundtrip
found 1 day ago
Select Sun Country Airlines flight, departing Thu, Oct 15 from Seattle to Washington, returning Mon, Oct 19, priced at CA $595 found 1 day ago
United
Sat, Nov 7 - Wed, Nov 11
SEA
Seattle
IAD
Washington
CA $675 Roundtrip, found 7 hours ago
CA $675
Roundtrip
found 7 hours ago
Select United flight, departing Sat, Nov 7 from Seattle to Washington, returning Wed, Nov 11, priced at CA $675 found 7 hours ago

Alternative airports near Washington

Prices were available within the past 7 days. Prices and availability are subject to change.

Select flight to Ronald Reagan Washington National DCA. Closest option available. Average driving time to city centre is 8 minutes. Flights from CA $832
DCA
Ronald Reagan Washington National
Closest
Average driving time to city centre8 min
Flights from CA $832

Find the cheapest month to fly from Seattle (SEA) to Washington (IAD)

September is typically the cheapest month to fly

From CA $353 - CA $456 per traveller.

Frequently asked questions

How much does a flight from Seattle, WA (SEA-Seattle - Tacoma Intl.) to Washington, DC (IAD-Washington Dulles Intl.) cost?
You can find cheap one-way flights from CA $275 and cheap return flights from CA $520 SEA to IAD with Expedia. One-way flights typically cost between CA$206 and CA$926, and return flights often range between CA$483 and CA$1816. Flight prices vary based on the month and day of the week you want to travel, as well as the airline and how far in advance you book your ticket. Filter your search on Expedia by "Price (lowest to highest)" to see the cheapest fares first, and use the Price Tracking tool to receive alerts when SEA to IAD ticket fares go up or down.
What is the cheapest month to fly from Seattle, WA (SEA-Seattle - Tacoma Intl.) to Washington, DC (IAD-Washington Dulles Intl.)?
January is typically the cheapest month to fly from Seattle - Tacoma Intl. (SEA) to Washington Dulles Intl. (IAD), with average return fares around CA$479. January sees lower prices because it falls after the holiday travel rush, when demand drops and airlines compete for bookings. September and October are also good months to find deals on this route.
Which airlines fly direct from Seattle, WA (SEA-Seattle - Tacoma Intl.) to Washington, DC (IAD-Washington Dulles Intl.)?
There are 3 airlines offering direct flights from Seattle - Tacoma Intl. (SEA) to Washington Dulles Intl. (IAD). Here are some of the top carriers:
  • United operates 26 direct flights from Seattle - Tacoma Intl. to Washington Dulles Intl. every week.
  • Qatar Airways operates 21 direct flights from Seattle - Tacoma Intl. to Washington Dulles Intl. every week.
  • Delta operates 7 direct flights from Seattle - Tacoma Intl. to Washington Dulles Intl. every week.
What is the cheapest airline that flies from Seattle, WA (SEA-Seattle - Tacoma Intl.) to Washington, DC (IAD-Washington Dulles Intl.)?
Sun Country Airlines is one of the cheapest airlines offering connecting return flights from Seattle - Tacoma Intl. (SEA) to Washington Dulles Intl. (IAD), with tickets starting from around CA$387 for flights that can be booked for departure within the next year. United is one of the cheapest airlines offering nonstop return flights from Seattle - Tacoma Intl. (SEA) to Washington Dulles Intl. (IAD), with tickets starting from around CA$391 for flights that can be booked for departure within the next year. These prices are per adult for economy/coach class. Use Expedia's search tool to compare the prices and schedules of airlines that fly this route to find the best option for your plans and budget.
How do I find cheap flights from Seattle, WA (SEA-Seattle - Tacoma Intl.) to Washington, DC (IAD-Washington Dulles Intl.)?
To find a cheap flight from Seattle, WA (SEA-Seattle - Tacoma Intl.) to Washington, DC (IAD-Washington Dulles Intl.), be flexible with your dates. Traveling outside of peak vacation months and booking a mid-week flight can help you save. Early morning and late night flights are often more affordable, too. Expedia allows you to compare flight times, airlines and routes all in one place to find low fares. You can also set up Price Tracking and receive alerts when fares go up or down.
What is the best airline to fly with from Seattle, WA (SEA-Seattle - Tacoma Intl.) to Washington, DC (IAD-Washington Dulles Intl.)?
The best airline to fly with from Seattle, WA (SEA-Seattle - Tacoma Intl.) to Washington, DC (IAD-Washington Dulles Intl.) will differ from traveler to traveler. If you like to fly early, Alaska Airlines offers early morning flights. If price is the most important factor, Delta typically offers the lowest fares. United offers the most daily flights from Seattle, WA (SEA-Seattle - Tacoma Intl.) to Washington, DC (IAD-Washington Dulles Intl.), which is great if flexibility is what you value most. The best carrier for this journey could also be the one you have a loyalty membership with, as flying with that airline or another airline within the same alliance could help you collect points or enjoy lounge access.
What is the best time to fly from Seattle, WA (SEA-Seattle - Tacoma Intl.) to Washington, DC (IAD-Washington Dulles Intl.)?
The cheapest months to fly from Seattle - Tacoma Intl. (SEA) to Washington Dulles Intl. (IAD) are typically January and September, with average return flights around CA$479. May is a popular month for this route, meaning you'll find plenty of flight options. While there isn't a single month that is both the cheapest and most popular, if you're looking for the best value, consider January or September for lower fares. If having a wide selection of flights is your priority, May offers many choices.
How many flights per day from Seattle, WA (SEA-Seattle - Tacoma Intl.) to Washington, DC (IAD-Washington Dulles Intl.)?
You'll find around 5 nonstop flights per day from Seattle - Tacoma Intl. (SEA) to Washington Dulles Intl. (IAD). For even more choices, look at flights that include layovers, as there are approximately 76 connecting flights per day. Some common connection points include San Francisco Intl. (SFO), Denver Intl. (DEN), and O'Hare Intl. (ORD).
What is the earliest flight from Seattle, WA (SEA-Seattle - Tacoma Intl.) to Washington, DC (IAD-Washington Dulles Intl.)?
The earliest flight from Seattle - Tacoma Intl. (SEA) to Washington Dulles Intl. (IAD) typically departs around 12:05 AM local time. This flight is operated by American Airlines and is a seasonal service, active in February. An early departure like this can help you make the most of your time at your destination. To compare early flights on Expedia, select the "Early Morning" and "Morning" filters in your search.
What day of the week has the most flights from Seattle, WA (SEA-Seattle - Tacoma Intl.) to Washington, DC (IAD-Washington Dulles Intl.)?
You'll typically find the most flights from Seattle - Tacoma Intl. (SEA) to Washington Dulles Intl. (IAD) on a Friday, with around 65 flights available. This gives you plenty of options for your travel plans. Major airlines on this route include United, Alaska Airlines, and Delta. Flight options are notably more on Fridays compared to other days of the week, offering you greater flexibility.
What are the most popular departure times for flights from Seattle, WA (SEA-Seattle - Tacoma Intl.) to Washington, DC (IAD-Washington Dulles Intl.)?
The most popular departure times for flights from Seattle, WA (SEA-Seattle - Tacoma Intl.) to Washington, DC (IAD-Washington Dulles Intl.) are in the early morning, from 6am to 9am. Many major carriers, including United, Alaska Airlines and Delta, offer flights during this window. Many travelers prefer this because it allows for an early arrival at your destination, giving you a full day for business or exploring.
How long does it take to fly from Seattle, WA (SEA-Seattle - Tacoma Intl.) to Washington, DC (IAD-Washington Dulles Intl.)?
Flying from Seattle - Tacoma Intl. (SEA) to Washington Dulles Intl. (IAD) covers a distance of approximately 3,701 kilometres. A non-stop flight typically takes around 5 hours. If you opt for a flight with one stop, your travel time will be longer, usually around 9 hours 30 minutes. Flights with two or more stops generally take about 11 hours. Keep in mind that actual flight times can vary due to factors like wind patterns and air traffic, so it's always a good idea to allow for some extra time when planning your trip.
Can you fly business or first class from Seattle, WA (SEA-Seattle - Tacoma Intl.) to Washington, DC (IAD-Washington Dulles Intl.)?
You can fly business class or first class between SEA and IAD. You can fly business class with Frontier Airlines and Delta.First class cabins are available on Alaska Airlines, United, Delta, and American Airlines.
How do I earn miles on a Seattle, WA (SEA-Seattle - Tacoma Intl.) to Washington, DC (IAD-Washington Dulles Intl.) flight with Expedia?
It's easy to earn miles on a Seattle, WA (SEA-Seattle - Tacoma Intl.) to Washington, DC (IAD-Washington Dulles Intl.) flight when you book with Expedia. Before you confirm your booking, simply select your frequent flyer program and enter your program number. As a member of One Key™, you can also earn OneKeyCash™* on top of your airline miles when you book with Expedia.*Excludes taxes and fees. OneKeyCash is not redeemable for cash and can only be used on Expedia and other participating brands.
What airports do you fly into for Washington, DC (IAD) from Seattle, WA (SEA)?
If you're planning to travel to Washington from Seattle - Tacoma Intl. (SEA), you can fly directly into Washington Dulles Intl. (IAD). Some flights may connect through major hubs like Harry Reid International Airport (LAS), San Francisco Intl. (SFO), or Sky Harbor Intl. (PHX) before reaching Washington. Compare routes and airports on Expedia to find the best flight options for your travel plans.
Is it cheaper to buy a plane ticket from Seattle, WA (SEA-Seattle - Tacoma Intl.) to Washington, DC (IAD-Washington Dulles Intl.) at the last minute?
Typically, booking a last minute flight from Seattle, WA (SEA-Seattle - Tacoma Intl.) to Washington, DC (IAD-Washington Dulles Intl.) will be more expensive than booking in advance. As the departure date approaches, there are usually fewer seats available which can drive up the cost. However, if there's some wiggle room with your travel dates and times, you could bag a cheap last-minute fare.
Is it cheaper to book a Seattle, WA (SEA-Seattle - Tacoma Intl.) to Washington, DC (IAD-Washington Dulles Intl.) flight and hotel package?
Securing a Seattle, WA (SEA-Seattle - Tacoma Intl.) to Washington, DC (IAD-Washington Dulles Intl.) flight and hotel package is usually cheaper than booking separately. With Expedia, you can enjoy the ease of organizing your travels all in one place. Select from our extensive range of stays and then add flights, activities and car rentals to your booking. Bundle everything together, and you could save hundreds of dollars.
Can I cancel or change the date of my flight from Seattle, WA (SEA-Seattle - Tacoma Intl.) to Washington, DC (IAD-Washington Dulles Intl.)?
If you booked your Seattle, WA (SEA-Seattle - Tacoma Intl.) to Washington, DC (IAD-Washington Dulles Intl.) flight within the last 24 hours, you may be able to modify or cancel it without any fees. Depending on the airline and the type of ticket you have, additional charges may apply for changes beyond this timeframe. Airline policies and contact information can be found in your itinerary or confirmation email. Or, head to our Customer Service portal if you'd like more information.

Travel information

Origin airport
Seattle - Tacoma Intl.
Destination airport
Washington Dulles Intl.
Airlines serving
Alaska Airlines, American Airlines, Delta, United
Roundtrip price
CA $520
Distance
3679 km
Average flight time
8 hours 4 mins

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Seattle to Chantilly Flights

The easy way to book your flights from Seattle to Washington 

With Expedia, it’s simple to find and book flights to Washington from Seattle whether you’re traveling for business or pleasure. Enter your travel dates, hit search, and choose your flight from 20 airlines that cover this route. There are nonstop flights to Washington Dulles Intl., too.  

Choose your preferred carrier and cabin class with the advanced search tool and select your ideal departure time. Then, if you want, you can see just nonstop or refundable flights. And if you’re traveling last minute, just enter the date to check out flights from Seattle to Washington today, tomorrow, or this week.  

 

Save dollars with cheap flights from Seattle - Tacoma Intl., SEA to Washington Dulles Intl., IAD 

Sort your search results by price to find great deals on your flight from Seattle to Washington—you get all your cheapest options first. Grab yourself a bargain now—the lowest price on flights to Washington from Seattle currently is just CA $520 rising to CA $675.  

Here are more money-saving tips: 

  • Fly in October when flight prices are normally at their lowest 
  • Book about a month to 6 weeks before you travel for the best prices to Washington  
  • Avoid peak season and weekends when flights can cost more
  • Early morning and late-night flights are sometimes cheaper, so try varying your travel times 
  • One surefire way to save money on your flight is to book your flight and hotel together with Expedia. Sometimes, the savings are so large that the flight is basically free! 

 

Reasons to choose Expedia for your flight to Washington from Seattle 

Whatever your destination, budget, or reason to travel, in just one quick search, you can choose from loads of flights, airlines, and cabin classes. The filters make it quick and easy to find your ideal flights, and if you choose one of the flexible options, you won’t be charged to change your flight. So book your flight to Washington with Expedia today.

Seattle to Chantilly Flights

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