$139 Cheap Flights from Washington (IAD) to Seattle (SEA)

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Cheap Flights from Washington to Seattle (IAD-SEA)

Prices were available within the past 7 days and start at $139 for one-way flights and $269 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Bargain Flight
Wed, May 29 - Wed, Jun 5
IAD
Washington
SEA
Seattle
$269 Roundtrip, found 6 hours ago
$269
Roundtrip
found 6 hours ago
Select Bargain Flight flight, departing Wed, May 29 from Washington to Seattle, returning Wed, Jun 5, priced at $269 found 6 hours ago
Alaska Airlines
Wed, May 29 - Wed, May 29
IAD
Washington
SEA
Seattle
$271 Roundtrip, found 1 hour ago
$271
Roundtrip
found 1 hour ago
Select Alaska Airlines flight, departing Wed, May 29 from Washington to Seattle, returning Wed, May 29, priced at $271 found 1 hour ago
Bargain Flight
Wed, Jun 5 - Wed, Jun 5
IAD
Washington
SEA
Seattle
$273 Roundtrip, found 1 hour ago
$273
Roundtrip
found 1 hour ago
Select Bargain Flight flight, departing Wed, Jun 5 from Washington to Seattle, returning Wed, Jun 5, priced at $273 found 1 hour ago
Bargain Flight
Wed, May 29 - Sat, Jun 8
IAD
Washington
SEA
Seattle
$275 Roundtrip, just found
$275
Roundtrip
just found
Select Bargain Flight flight, departing Wed, May 29 from Washington to Seattle, returning Sat, Jun 8, priced at $275 just found
Bargain Flight
Wed, Sep 18 - Wed, Sep 25
IAD
Washington
SEA
Seattle
$276 Roundtrip, just found
$276
Roundtrip
just found
Select Bargain Flight flight, departing Wed, Sep 18 from Washington to Seattle, returning Wed, Sep 25, priced at $276 just found
United
Tue, Jun 4 - Wed, Jun 12
IAD
Washington
SEA
Seattle
$277 Roundtrip, found 4 hours ago
$277
Roundtrip
found 4 hours ago
Select United flight, departing Tue, Jun 4 from Washington to Seattle, returning Wed, Jun 12, priced at $277 found 4 hours ago
Bargain Flight
Sun, Jun 2 - Wed, Jun 12
IAD
Washington
SEA
Seattle
$279 Roundtrip, just found
$279
Roundtrip
just found
Select Bargain Flight flight, departing Sun, Jun 2 from Washington to Seattle, returning Wed, Jun 12, priced at $279 just found
Bargain Flight
Thu, May 30 - Tue, Jun 4
IAD
Washington
SEA
Seattle
$279 Roundtrip, found 11 hours ago
$279
Roundtrip
found 11 hours ago
Select Bargain Flight flight, departing Thu, May 30 from Washington to Seattle, returning Tue, Jun 4, priced at $279 found 11 hours ago
Bargain Flight
Fri, May 31 - Mon, Jun 10
IAD
Washington
SEA
Seattle
$280 Roundtrip, just found
$280
Roundtrip
just found
Select Bargain Flight flight, departing Fri, May 31 from Washington to Seattle, returning Mon, Jun 10, priced at $280 just found
United
Tue, Jun 4 - Wed, Jun 12
IAD
Washington
SEA
Seattle
$281 Roundtrip, found 4 hours ago
$281
Roundtrip
found 4 hours ago
Select United flight, departing Tue, Jun 4 from Washington to Seattle, returning Wed, Jun 12, priced at $281 found 4 hours ago
Flights from Washington (IAD) to Seattle (SEA)
Origin airport
Washington Dulles Intl.
Destination airport
Seattle - Tacoma Intl.
Airlines serving
Alaska Airlines, American Airlines, Delta, Sun Country Airlines, United
Roundtrip price
$268
Distance
2299 mi
Average flight time
2 hours 48 mins

Washington to Seattle Flights

Whether you’re looking for a grand adventure or just want to get away for a last-minute break, flights from Washington to Seattle offer the perfect respite. Not only does exploring Seattle provide the chance to make some magical memories, dip into delectable dishes, and tour the local landmarks, but the cheap airfare means you won’t bust your budget. So no matter whether your ideal itinerary involves flying one way, non-stop, or round trip, you’re bound to find flights that match your schedule on Expedia, and at prices that won’t shock your wallet.

Bagging a cheap flight from Washington to Seattle may mean more dollars to spend on for one-of-a-kind souvenirs when you arrive, but it doesn’t mean you have to skimp on your travel experience, as Expedia offers a sizzling selection of cheap airlines that’ll put you in your happy place on their planes, whether that’s getting lost in a hair-raising airport thriller, dreaming on the passing landscape over a glass of bubbly, or jotting down your vacation bucket list at 38,000 feet. There’s also bound to be plenty of opportunities to snap a few photos of the high life that will make your friends green with envy. After all, enjoying the journey is part of the fun.

With so many affordable flights and so many wonderful adventures awaiting you, there’s no reason to put off booking a fantastic flight from IAD to SEA today. So don’t leave it to the last minute to make your dream trip a reality: pack your bags with your go-to travel accessories, put together your list of must-see attractions and can’t-miss activities, and get ready to broaden your horizons – with Expedia, the wonders of Seattle are only a plane trip away. Book your travel arrangements with us today!

If you would like to book flights to Seattle more flexibly many prefer to purchase one-way tickets with options to take different airlines. A one way ticket to Seattle is $139 now!

Frequently asked questions

How much is a one-way flight from IAD to SEA?
You can get one-way Washington flights to Seattle starting from $137. This is based on the lowest price found on Expedia for this route with a departure date within the next three months and was updated on May 1 2024 and has not changed since. This specific fare is for an Alaska Airlines flight, leaving from Washington Dulles Intl. Airport (IAD) on May 6 2024 and coming in to land at Sea-Tac Airport.
How long does it take to fly from Dulles Intl. Airport to SEA?
A direct flight with United Airlines takes about 5 hours and 44 minutes. Hop on the 9:05AM flight from IAD and arrive at Sea-Tac Airport at 11:49AM. Score an epic deal on this route when you book your fare with Expedia.
Is it cheaper to buy a plane ticket from IAD to SEA last minute?
Booking your flight from Dulles Intl. Airport to Seattle - Tacoma Intl. Airport (SEA) last minute could save you a pretty penny if you happen to find a terrific deal. However, tickets don’t usually get cheaper as the date of departure nears. If you choose to wait, flights could also be sold out or the best seats gone (that could mean the middle seat!). If you’d rather not hedge your bets, book well ahead of when you want to leave. In fact, Expedia has some of the biggest deals up to a year in advance. If your favorite carrier hasn’t released its airfares yet, check back regularly as offers are constantly updated on Expedia.
What is the cheapest airline flying from IAD to Sea-Tac Airport in the next 90 days?
With plane tickets from $137 for a flight from Washington to Seattle, Alaska Airlines is the cheapest airline found on Expedia. This price is based on airfares found on Expedia departing within the next 90 days and was updated on May 1 2024 and has not changed since. The flight sets off from IAD on May 6 2024 and lands at Sea-Tac Airport.
What's the cheapest price for a flight from Dulles Intl. Airport to Sea-Tac Airport next month?
With a one-way flight from Washington to Seattle on sale for $137, you’ll have extra dollars to splash on fun adventures. This price was found after searching all available flights on Expedia within the next 30 days. This particular service departs Dulles Intl. Airport on May 6 2024, touches down at SEA and is operated by Alaska Airlines. Pricing info was last updated on May 1 2024 and has not changed since.
What airline has the least delays from IAD to SEA?
If you don’t want to be stuck in the departure lounge — or worse, have your vacation upended due to a flight delay — opt for Alaska Airlines. Around 93% of its Washington Dulles Intl. Airport (IAD) to Sea-Tac Airport services land on time. You can review your flight status before you get to the airport through the free Expedia App. It’ll also provide you with real-time notifications about other useful things, such as last-minute gate changes and directions to your hotel. Everything you need to know is in your pocket with this handy travel companion.
Can I find cheap nonstop flights from Washington Dulles Intl. Airport (IAD) to Sea-Tac Airport in the next three months?
The next trip you take doesn’t need to break the bank. We’ve come across a roundtrip nonstop flight from Washington to Seattle within the next 90 days for $268. This price was found after looking at all available flights on Expedia with a departure date within the next three months and was last updated on May 1 2024. The flight via Alaska Airlines jets off from IAD on May 11 2024 and arrives at Seattle - Tacoma Intl. Airport (SEA). It has a return date of May 20 2024.To locate nonstop cheap flights from Washington Dulles Intl. Airport (IAD) to Sea-Tac Airport, use our filters once you’ve hit search. Just click “Nonstop” under “Filter by” on the left side of the page to view your options. Your results will be arranged from the lowest price, so you’ll see the cheapest nonstop fares first. You can also compare prices for surrounding days by clicking “Flexible dates” located on the same page.
What airports do you fly into for Seattle from Sterling?
From Sterling, you can fly into Seattle through Seattle - Tacoma Intl. Airport (SEA), Renton Municipal Airport (RNT) and Boeing Field Airport (BFI). Find out which terminal is best for you before making your decision. If you go with Seattle - Tacoma Intl. Airport (SEA), it’s roughly 12 mi south of downtown. Use the money you save when booking your fare with Expedia to enjoy the city’s awesome attractions, such as Space Needle and Pike Place Market.
What are the most popular departure times for flights from IAD to Seattle - Tacoma Intl. Airport (SEA)?
For United Airlines flights making their way from Washington Dulles Intl. Airport (IAD) to Seattle - Tacoma Intl. Airport (SEA), the peak period is between 8:00 AM - 9:00 AM. If you’d like to avoid any holdups, fly in the morning. This allows you to avoid the heavy air traffic that builds up around airports as the day goes by.
Can I change the date of my flight from Washington Dulles Intl. Airport (IAD) to Sea-Tac Airport?
We know plans can get upended, so Expedia is here to help make amending your flight as easy as possible. To start, find your IAD to Sea-Tac Airport itinerary through the Expedia Trips portal and browse the ticket conditions and rules about what changes you can make. If you booked in the last 24 hours, some carriers will let you cancel at no cost and organize new flights. If you bought your fare more than 24 hours ago, contact us through our Customer Service portal to learn more about your options.
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