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

Cheapflights users have booked flights from Washington, D.C. Dulles Intl Airport to Seattle round-trip from $257. Other airlines that can offer you cheap pricing are Hawaiian Airlines, from $261, and Alaska Airlines, from $264. American Airlines is currently priced 37% below the average price you’ll pay for this route.

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

To fly one-way, consider booking your trip with Alaska Airlines, which is currently one of the cheapest options available, starting at $148. Delta flights start at $149 while deals on Sun Country Air start at $153 one-way.

In terms of precipitation, rainfall in Seattle ranges from 0.7 - 6.6 inches per month. November is typically the wettest month, when rainfall can reach 6.6 in. July is typically the driest time to visit Seattle when rainfall is around 0.7 in.

If weather is an important factor for your trip to Seattle, 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 66.2 F. Travelers looking to avoid the cold should look outside of December, when temperatures are typically at their lowest (around 41.0 F).

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

The cheapest flight price from Washington, D.C. Dulles Intl Airport to Seattle is $141. On average you can expect to pay $1,168. The most popular route, (Washington, D.C. Dulles Intl - Seattle/Tacoma Intl), can usually be booked for $273.

What are the most popular airlines that fly from Washington, D.C. Dulles Intl Airport to Seattle?

When booking a flight from Washington, D.C. Dulles Intl Airport to Seattle, you may want to consider flying on American Airlines, Alaska Airlines or Delta as they are the most popular for this route.

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

Leaving on a Monday is a viable option for saving on travel. Heavily demanded days of the week can typically drive up the prices you see. Booking your travel for a less competitive day can save up to 29% on the overall cost on flights from Washington, D.C. Dulles Intl Airport to Seattle.

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

September is one of the best times of the year to fly to Seattle from Washington, D.C. Dulles Intl Airport. Prices for September average $405 per person but you can even find prices for as low as $186. The most expensive prices can be found in the month of December. Opting for a September flight can save you 22% on your journey compared to booking in December

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

Seattle/Tacoma Intl (SEA), located 11.4 mi from the city center, is the airport you fly into when you book flights from Washington, D.C. Dulles Intl to Seattle. 7 airlines have flights to Seattle/Tacoma Intl from Washington, D.C. Dulles Intl on a regular basis. Booking flights from Washington, D.C. Dulles Intl to Seattle/Tacoma Intl should not be difficult; the airport handles an average of 20 inbound flights from Washington, D.C. Dulles Intl per day.

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

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

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

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

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

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

$148+ Flights from Washington, D.C. Dulles Intl Airport to Seattle

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Cheapflights Tip: The best prices from Washington, D.C. Dulles Intl to Seattle/Tacoma Intl are usually found in February or January, booked 58 days in advance, depart on a Tuesday or Wednesday and return on a Tuesday

Cheap flight deals from Dulles Intl to Seattle

Round-trip from	$257 (American Airlines)
One-way from	$148 (Alaska Airlines)
Popular in	December
Cheapest in	February
Average price	$457
Good round-trip deal	$364 or less
Good one-way deal	$201 or less

From Washington, D.C. Dulles Intl to Seattle/Tacoma Intl

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One-way flight from Washington, D.C. Dulles Intl to Seattle/Tacoma Intl

Search Deals

Highest demand for flights based on searches. 2% potential increase in price ($11 potential increase over avg. RT price).

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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 July 2025

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Price to beat on a round-trip flight from Washington, D.C. Dulles Intl to Seattle/Tacoma Intl.

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Price to beat on a one-way flight from Washington, D.C. Dulles Intl to Seattle/Tacoma Intl.

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Find flight deals from Dulles Intl to Seattle

Cheapest flights from Dulles Intl to Seattle
Explore the most affordable flight options available from Dulles Intl to Seattle. Find the lowest fares from popular airlines and budget airlines, with prices last updated on July 18, 2025.

Wed 9/32:21 pmIAD - SEA

1 stop11h 08mAmerican Airlines

Tue 9/95:26 amSEA - IAD

1 stop8h 24mAmerican Airlines

Deal found 7/17

$257

Wed 8/136:30 amIAD - SEA

Nonstop5h 47mHawaiian Airlines

Wed 8/204:20 pmSEA - IAD

Nonstop5h 00mHawaiian Airlines

Deal found 7/16

$261

Sat 8/309:00 amIAD - SEA

Nonstop5h 43mAlaska Airlines

Sat 9/611:30 pmSEA - IAD

Nonstop5h 03mAlaska Airlines

Deal found 7/15

$264

Mon 8/117:30 amIAD - SEA

1 stop9h 36mFrontier

Thu 8/143:11 pmSEA - IAD

1 stop12h 23mFrontier

Deal found 7/16

$286

Thu 10/1611:52 amIAD - SEA

1 stop8h 33mSun Country Air

Sun 10/1911:59 pmSEA - IAD

1 stop8h 27mSun Country Air

Deal found 7/16

$289

Sat 9/131:00 pmIAD - SEA

1 stop12h 07mDelta

Tue 9/309:55 pmSEA - IAD

Nonstop5h 06mDelta

Deal found 7/17

$300

Sat 8/305:05 pmIAD - SEA

1 stop7h 45mSouthwest

Sat 9/207:35 amSEA - IAD

2 stops12h 10mSouthwest

Deal found 7/16

$302

Best flights from Dulles Intl to Seattle
Discover carefully curated flight deals from Dulles Intl to Seattle that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated July 18, 2025.

Wed 9/32:21 pmIAD - SEA

1 stop11h 08mAmerican Airlines

Tue 9/95:26 amSEA - IAD

1 stop8h 24mAmerican Airlines

Deal found 7/17

$257

Wed 8/136:30 amIAD - SEA

Nonstop5h 47mHawaiian Airlines

Wed 8/204:20 pmSEA - IAD

Nonstop5h 00mHawaiian Airlines

Deal found 7/16

$261

Sat 8/309:00 amIAD - SEA

Nonstop5h 43mAlaska Airlines

Sat 9/611:30 pmSEA - IAD

Nonstop5h 03mAlaska Airlines

Deal found 7/15

$264

Mon 8/117:30 amIAD - SEA

1 stop9h 36mFrontier

Thu 8/143:11 pmSEA - IAD

1 stop12h 23mFrontier

Deal found 7/16

$286

Wed 8/131:05 pmIAD - SEA

Nonstop5h 48mUnited Airlines

Tue 8/195:35 pmSEA - IAD

1 stop8h 49mUnited Airlines

Deal found 7/17

$287

Thu 10/1611:52 amIAD - SEA

1 stop8h 33mSun Country Air

Sun 10/1911:59 pmSEA - IAD

1 stop8h 27mSun Country Air

Deal found 7/16

$289

Sat 9/131:00 pmIAD - SEA

1 stop12h 07mDelta

Tue 9/309:55 pmSEA - IAD

Nonstop5h 06mDelta

Deal found 7/17

$300

Sat 8/305:05 pmIAD - SEA

1 stop7h 45mSouthwest

Sat 9/207:35 amSEA - IAD

2 stops12h 10mSouthwest

Deal found 7/16

$302

Last-minute flights from Dulles Intl to Seattle
Discover last-minute flight deals from Dulles Intl to Seattle. Data last updated July 18, 2025 and is based on user searches.

Wed 7/2312:40 pmIAD - SEA

1 stop7h 25mSun Country Air

Wed 7/306:27 pmSEA - IAD

1 stop13h 12mSun Country Air

Deal found 7/16

$407

Wed 7/2312:40 pmIAD - SEA

1 stop7h 25mMultiple Airlines

Mon 8/43:11 pmSEA - IAD

1 stop12h 23mMultiple Airlines

Deal found 7/16

$431

Wed 7/237:30 amIAD - SEA

Nonstop5h 47mDelta

Thu 8/79:55 pmSEA - IAD

Nonstop5h 02mDelta

Deal found 7/16

$493

Thu 7/242:44 pmIAD - SEA

2 stops12h 50mFrontier

Thu 7/313:11 pmSEA - IAD

1 stop12h 23mFrontier

Deal found 7/16

$440

Thu 7/245:25 pmIAD - SEA

1 stop9h 26mAlaska Airlines

Wed 8/67:05 pmSEA - IAD

1 stop8h 45mAlaska Airlines

Deal found 7/16

$512

Mon 8/117:30 amIAD - SEA

1 stop9h 36mFrontier

Thu 8/143:11 pmSEA - IAD

1 stop12h 23mFrontier

Deal found 7/16

$286

Mon 8/113:26 pmIAD - SEA

1 stop11h 33mDelta

Tue 8/199:55 pmSEA - IAD

Nonstop5h 00mDelta

Deal found 7/16

$310

Mon 8/118:50 pmIAD - SEA

1 stop14h 12mSun Country Air

Thu 8/1411:59 pmSEA - IAD

1 stop8h 56mSun Country Air

Deal found 7/17

$314

Wed 8/136:30 amIAD - SEA

Nonstop5h 47mHawaiian Airlines

Wed 8/204:20 pmSEA - IAD

Nonstop5h 00mHawaiian Airlines

Deal found 7/16

$261

Wed 8/131:05 pmIAD - SEA

Nonstop5h 48mUnited Airlines

Tue 8/195:35 pmSEA - IAD

1 stop8h 49mUnited Airlines

Deal found 7/17

$287

Tue 8/1911:51 amIAD - SEA

1 stop8h 06mAmerican Airlines

Tue 8/268:10 amSEA - IAD

1 stop7h 42mAmerican Airlines

Deal found 7/17

$339

Sat 8/309:00 amIAD - SEA

Nonstop5h 43mAlaska Airlines

Sat 9/611:30 pmSEA - IAD

Nonstop5h 03mAlaska Airlines

Deal found 7/15

$264

One-way flights from Dulles Intl to Seattle
Search for one-way flight options from Dulles Intl to Seattle. Find affordable one-way fares based on user searches. Data last updated July 18, 2025.

Wed 8/135:25 pmIAD - SEA

1 stop9h 26mAlaska Airlines

Deal found 7/17

$148

Mon 8/187:35 amIAD - SEA

Nonstop5h 45mDelta

Deal found 7/16

$149

Fri 10/36:30 pmIAD - SEA

1 stop25h 31mSun Country Air

Deal found 7/16

$153

Sat 8/306:09 pmIAD - SEA

Nonstop5h 42mHawaiian Airlines

Deal found 7/16

$160

Thu 8/77:30 amIAD - SEA

1 stop9h 36mFrontier

Deal found 7/17

$162

Wed 8/202:25 pmIAD - SEA

2 stops12h 40mSouthwest

Deal found 7/17

$184

Thu 9/251:20 pmIAD - SEA

1 stop8h 29mUnited Airlines

Deal found 7/17

$189

Wed 8/67:30 amIAD - SEA

1 stop11h 55mMultiple Airlines

Deal found 7/17

$191

Fri 8/156:27 amIAD - SEA

2 stops13h 15mAmerican Airlines

Deal found 7/17

$214

Cheapflights Fare Finder

Use the filters below to find and compare flights from Washington, D.C. Dulles Intl Airport to Seattle that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Washington, D.C.Seattle

IAD - SEA

IADSEA

Washington, D.C. Dulles Intl

Wed 9/3

2:21 pm-10:29 pm

1 stop11h 08m

Seattle/Tacoma Intl

Tue 9/9

5:26 am-4:50 pm

1 stop8h 24m

$257

Washington, D.C.Seattle

IAD - SEA

IADSEA

Washington, D.C. Dulles Intl

Wed 8/13

6:30 am-9:17 am

Nonstop5h 47m

Seattle/Tacoma Intl

Wed 8/20

4:20 pm-12:20 am

Nonstop5h 00m

$261

Washington, D.C.Seattle

IAD - SEA

IADSEA

Washington, D.C. Dulles Intl

Sat 8/30

9:00 am-11:43 am

Nonstop5h 43m

Seattle/Tacoma Intl

Sat 9/6

11:30 pm-7:33 am

Nonstop5h 03m

$264

Washington, D.C.Seattle

IAD - SEA

IADSEA

Washington, D.C. Dulles Intl

Mon 8/11

7:30 am-2:06 pm

1 stop9h 36m

Seattle/Tacoma Intl

Thu 8/14

3:11 pm-6:34 am

1 stop12h 23m

$286

Washington, D.C.Seattle

IAD - SEA

IADSEA

Washington, D.C. Dulles Intl

Wed 8/13

1:05 pm-3:53 pm

Nonstop5h 48m

Seattle/Tacoma Intl

Tue 8/19

5:35 pm-5:24 am

1 stop8h 49m

$287

Washington, D.C.Seattle

IAD - SEA

IADSEA

Washington, D.C. Dulles Intl

Thu 10/16

11:52 am-5:25 pm

1 stop8h 33m

Seattle/Tacoma Intl

Sun 10/19

11:59 pm-11:26 am

1 stop8h 27m

$289

Washington, D.C.Seattle

IAD - SEA

IADSEA

Washington, D.C. Dulles Intl

Sat 9/13

1:00 pm-10:07 pm

1 stop12h 07m

Seattle/Tacoma Intl

Tue 9/30

9:55 pm-6:01 am

Nonstop5h 06m

$300

Washington, D.C.Seattle

IAD - SEA

IADSEA

Washington, D.C. Dulles Intl

Sat 8/30

5:05 pm-9:50 pm

1 stop7h 45m

Seattle/Tacoma Intl

Sat 9/20

7:35 am-10:45 pm

2 stops12h 10m

$302

Washington, D.C.Seattle

IAD - SEA

IADSEA

Washington, D.C. Dulles Intl

Wed 8/13

8:10 am-4:54 pm

1 stop11h 44m

$148

Washington, D.C.Seattle

IAD - SEA

IADSEA

Washington, D.C. Dulles Intl

Mon 8/18

7:35 am-10:20 am

Nonstop5h 45m

$149

Flights are sorted by cheapest round-trip flights first.

Deals found on 7/17

Showing 1-10 of 17 results

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

Cheapflights partnered with top experts to bring you the best recommendations for your Washington, D.C. Dulles Intl Airport to Seattle trip

Airports

IAD

For a smooth check-in at IAD, locate your airline’s counter by walking around the first row if not visible initially.

SEA

Use the Link light rail from SEA to downtown Seattle for an affordable, 40-minute ride with ample luggage space.

Our travel experts

Ramsey Qubein

Expert on IAD

Brandon Schultz

Expert on SEA

Best time to book a flight from Dulles Intl to Seattle

Have a flexible travel schedule? Discover the best time to fly to Seattle from Dulles Intl 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 Washington, D.C. Dulles Intl Airport to Seattle

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

The price you pay for your flight from Washington, D.C. Dulles Intl Airport to Seattle may vary depending on when you book. For the best chance of a lower fare, look to book 58 days in advance of your trip. Fares are likely to increase a fortnight or so before your departure date.

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

Currently, January is the cheapest month in which you can book a flight from Washington, D.C. Dulles Intl Airport to Seattle (average of $238). Flying from Washington, D.C. Dulles Intl Airport to Seattle 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 IAD to SEA?

One of the essential ways to save on airfare from Washington, D.C. Dulles Intl Airport to Seattle is to remain as flexible as possible. Flights that are in the morning tend to be the most expensive. A flight in the evening could potentially save you up to 18% on airfare.

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

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

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

The most flights from IAD to SEA are scheduled on a Thursday (31 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (11 on average).

Reviews of airlines servicing Seattle

See what other customers who have flown with Alaska Airlines, Southwest, and Delta from Washington, D.C. Dulles Intl Airport to Seattle have to say. You can also see how each airline compares in terms of entertainment options, comfort, food, crew/service, and boarding process.

Alaska Airlines

8.0

Very good

10,000 reviews

Reviews

1 / 20

10.0

Excellent

Anonymous,Jul 2025

EUG - SEA

Mobility support was fabulous No flight entertainment that I was aware of.

Alaska Airlines

8.0

Very good

10,000 reviews

Alaska Airlines

8.0

Very good

10,000 reviews

Reviews

1 / 20

10.0

Excellent

Anonymous,Jul 2025

EUG - SEA

Mobility support was fabulous No flight entertainment that I was aware of.

Southwest

8.0

Very good

4,239 reviews

Alaska Airlines

8.0

Very good

10,000 reviews

Reviews

1 / 20

10.0

Excellent

Anonymous,Jul 2025

EUG - SEA

Mobility support was fabulous No flight entertainment that I was aware of.

Delta

8.0

Very good

7,959 reviews

Alaska Airlines

8.0

Very good

10,000 reviews

Reviews

1 / 20

10.0

Excellent

Anonymous,Jul 2025

EUG - SEA

Mobility support was fabulous No flight entertainment that I was aware of.

Hawaiian Airlines

7.8

Good

2,581 reviews

Alaska Airlines

8.0

Very good

10,000 reviews

Reviews

1 / 20

10.0

Excellent

Anonymous,Jul 2025

EUG - SEA

Mobility support was fabulous No flight entertainment that I was aware of.

United Airlines

7.4

Good

8,864 reviews

Alaska Airlines

8.0

Very good

10,000 reviews

Reviews

1 / 20

10.0

Excellent

Anonymous,Jul 2025

EUG - SEA

Mobility support was fabulous No flight entertainment that I was aware of.

Related info for your journey

What airport do you fly into for flights to Seattle from Washington, D.C. Dulles Intl?
Seattle/Tacoma Intl (SEA), located 11.4 mi from the city center, is the airport you fly into when you book flights from Washington, D.C. Dulles Intl to Seattle. 7 airlines have flights to Seattle/Tacoma Intl from Washington, D.C. Dulles Intl on a regular basis. Booking flights from Washington, D.C. Dulles Intl to Seattle/Tacoma Intl should not be difficult; the airport handles an average of 20 inbound flights from Washington, D.C. Dulles Intl per day.
What are the cheapest airlines flying from Washington, D.C. Dulles Intl Airport to Seattle round-trip?
Cheapflights users have booked flights from Washington, D.C. Dulles Intl Airport to Seattle round-trip from $257. Other airlines that can offer you cheap pricing are Hawaiian Airlines, from $261, and Alaska Airlines, from $264. American Airlines is currently priced 37% below the average price you’ll pay for this route.
What are the cheapest airlines to fly from Washington, D.C. Dulles Intl Airport to Seattle one-way?
To fly one-way, consider booking your trip with Alaska Airlines, which is currently one of the cheapest options available, starting at $148. Delta flights start at $149 while deals on Sun Country Air start at $153 one-way.
What are the most reliable airlines from Washington, D.C. Dulles Intl Airport to Seattle?
The top 3 most reliable airlines when flying from Washington, D.C. Dulles Intl Airport to Seattle are Japan Airlines (97%), China Eastern (82%) and Delta (82%).
What are the cheapest flights from Washington, D.C. Dulles Intl Airport to Seattle?
The cheapest flight price from Washington, D.C. Dulles Intl Airport to Seattle is $141. On average you can expect to pay $1,168. The most popular route, (Washington, D.C. Dulles Intl - Seattle/Tacoma Intl), can usually be booked for $273.
Can I find deals for flights from Dulles Intl to Seattle that include hotel bookings?
Yes. In addition to deals on Dulles Intl to Seattle flights, Cheapflights offers vacation packages that include both flights and hotel.
How can I find direct flights from Dulles Intl to Seattle?
After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Dulles Intl to Seattle.
Can I find deals for business class flights from Dulles Intl to Seattle?
Yes. Cheapflights offers flight deals from Dulles Intl to Seattle 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 Washington, D.C. Dulles Intl Airport to Seattle?
Currently, January is the cheapest month in which you can book a flight from Washington, D.C. Dulles Intl Airport to Seattle (average of $238). Flying from Washington, D.C. Dulles Intl Airport to Seattle 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

SeaTac

Tukwila

Tacoma

Lakewood

Ocean Shores

Lynnwood

Lacey

Leavenworth

Renton

Olympia

Puyallup

Cle Elum

Shoreline

Kent

Chehalis

Kirkland

Aberdeen

Federal Way

Shelton

Silverdale

Browse thousands of different options on Cheapflights for your next trip

Alternative routes for Dulles Intl to Seattle

Complete your trip

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Other flights to Seattle

Top 7 airlines flying from Dulles Intl to Seattle

Airline	Cheapest	Average	Flexibility	On-time
Frontier	Cheapest$111	Average$240	FlexibilityNo cancel fee	On-time62%
Sun Country Air	Cheapest$144	Average$370	FlexibilityNo cancel fee	On-time83%
Hawaiian Airlines	Cheapest$168	Average$391	FlexibilityNo cancel fee	On-time85%
Delta	Cheapest$218	Average$382	FlexibilityNo cancel fee	On-timeN/A
Alaska Airlines	Cheapest$263	Average$426	FlexibilityNo cancel fee	On-time75%
United Airlines	Cheapest$284	Average$470	FlexibilityNo cancel fee	On-time69%
American Airlines	Cheapest$297	Average$522	FlexibilityNo cancel fee	On-time71%

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$148+ Cheap flights from Dulles Intl (IAD) to Seattle (SEA)

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 8/13. Fares are subject to change and may not be available on all flights or dates of travel.

Find cheap flights from Dulles Intl to Seattle with Cheapflights

1. Tell us where you want to go

2. Select your favorite providers

3. Compare prices and book

Cheapflights Tip: The best prices from Washington, D.C. Dulles Intl to Seattle/Tacoma Intl are usually found in February or January, booked 58 days in advance, depart on a Tuesday or Wednesday and return on a Tuesday

Cheap flight deals from Dulles Intl to Seattle

Round-trip from

One-way from

Popular in

Cheapest in

Average price

Good round-trip deal

Good one-way deal

Find flight deals from Dulles Intl to Seattle

Cheapest flights from Dulles Intl to SeattleExplore the most affordable flight options available from Dulles Intl to Seattle. Find the lowest fares from popular airlines and budget airlines, with prices last updated on July 18, 2025.

Explore the most affordable flight options available from Dulles Intl to Seattle. Find the lowest fares from popular airlines and budget airlines, with prices last updated on July 18, 2025.

Cheapflights Fare Finder

Use the filters below to find and compare flights from Washington, D.C. Dulles Intl Airport to Seattle that are best for you.

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

Cheapflights partnered with top experts to bring you the best recommendations for your Washington, D.C. Dulles Intl Airport to Seattle trip

Airports

IAD

SEA

Our travel experts

Best time to book a flight from Dulles Intl to Seattle

Have a flexible travel schedule? Discover the best time to fly to Seattle from Dulles Intl with our price prediction graph.

Cheapflights Insights

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

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

Use this chart to determine the optimal time to book a round-trip flight from Dulles Intl to Seattle. Price data was last updated on July 11, 2025.

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

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

Find hourly flight availability from Dulles Intl to Seattle. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated July 18, 2025.

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

Use this chart to determine the cheapest time to fly round-trip from Dulles Intl to Seattle. Price data was last updated on July 13, 2025.

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

Explore weekly flight availability from Dulles Intl to Seattle. 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 July 18, 2025.

Reviews of airlines servicing Seattle

See what other customers who have flown with Alaska Airlines, Southwest, and Delta from Washington, D.C. Dulles Intl Airport to Seattle have to say. You can also see how each airline compares in terms of entertainment options, comfort, food, crew/service, and boarding process.

Related info for your journey

Find useful and relevant information for your journey from Dulles Intl to Seattle. 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 into for flights to Seattle from Washington, D.C. Dulles Intl?

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

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

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

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

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

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

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

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Cheapest flights from Dulles Intl to Seattle
Explore the most affordable flight options available from Dulles Intl to Seattle. Find the lowest fares from popular airlines and budget airlines, with prices last updated on July 18, 2025.