What’s the top layover airport for flights from Washington, D.C. Dulles Intl Airport to Seattle?

Las Vegas (LAS) – chosen by Cheapflights users on 67% of 1-stop itineraries from Washington, D.C. Dulles Intl Airport to Seattle on Cheapflights.

Which airport typically offers the quickest layover for flights from Washington, D.C. Dulles Intl Airport to Seattle?

Flights via Denver (DEN) offer the fastest connection on this route, with an average layover time of 2h 04m.

What’s the fastest layover option from Washington, D.C. Dulles Intl Airport to Seattle?

Flights via Denver (DEN) have the shortest average one-way travel time for 1-stop routes: 9h 44m.

What’s the cheapest layover airport for flights from Washington, D.C. Dulles Intl Airport to Seattle?

Las Vegas (LAS) is the most affordable 1-stop option, with an average round-trip price of $218.

How long is the flight from Washington, D.C. Dulles Intl Airport to Seattle?

There are many flights that can get you from Washington, D.C. Dulles Intl Airport to Seattle in 5h 59m. Fly via Delta to get the fastest option. Airlines will cover a distance of 2299 mi. Generally, flights for this route are nonstop.

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 $111. Other airlines that can offer you cheap pricing are Hawaiian Airlines, from $143, and Delta, from $158. Frontier is currently priced 72% 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 Frontier, which is currently one of the cheapest options available, starting at $116. Delta flights start at $129 while deals on Alaska Airlines start at $138 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 $119. On average you can expect to pay $1,192. The most popular route, (Washington, D.C. Dulles Intl - Seattle/Tacoma Intl), can usually be booked for $199.

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 ITA Airways (100%), United Airlines (87%) and Austrian Airlines (78%).

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 Alaska Airlines, United Airlines or Delta as they are the most popular for this route.

Most accurate provider : When it comes to deals on Washington, D.C. Dulles Intl Airport-Seattle flights, users find the pricing of eDreams to be most consistent on Cheapflights vs. eDreams Users can find the same prices on Washington, D.C. Dulles Intl Airport-Seattle flight deals on Cheapflights vs. eDreams >95% of the time. Price accuracy is based on data collected from Washington, D.C. Dulles Intl Airport-Seattle flight searches over the past month and is updated monthly.

Most trusted provider : When it comes to deals on Washington, D.C. Dulles Intl Airport-Seattle flights, Cheapflights users trust eDreams the most. eDreams 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 Washington, D.C. Dulles Intl Airport-Seattle flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

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. 6 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 4 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.

$125+ Flights from Washington, D.C. Dulles Intl Airport to Seattle

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Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”

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Cheapflights Tip: The best prices from Washington, D.C. Dulles Intl to Seattle/Tacoma Intl are usually found in January or February, booked 36 days in advance, depart on a Tuesday or Wednesday and return on a Thursday

Cheap 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 December 18, 2025.

Wed 12/316:20 amIAD - SEA

1 stop10h 38mUnited Airlines

Wed 1/78:10 amSEA - IAD

Nonstop5h 06mUnited Airlines

Deal found 12/17

$411

Wed 12/316:20 amIAD - SEA

1 stop10h 38mUnited Airlines

Tue 1/68:10 amSEA - IAD

Nonstop5h 06mUnited Airlines

Deal found 12/15

$412

Wed 12/316:00 amIAD - SEA

1 stop7h 35mDelta

Tue 1/63:20 pmSEA - IAD

Nonstop4h 50mDelta

Deal found 12/16

$442

Tue 12/305:31 pmIAD - SEA

1 stop8h 16mUnited Airlines

Tue 1/68:10 amSEA - IAD

Nonstop5h 06mUnited Airlines

Deal found 12/16

$472

Thu 12/255:55 pmIAD - SEA

Nonstop6h 02mUnited Airlines

Mon 1/128:10 amSEA - IAD

Nonstop5h 06mUnited Airlines

Deal found 12/17

$478

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 December 18, 2025.

Wed 1/147:30 amIAD - SEA

Nonstop5h 59mDelta

Tue 1/2011:10 pmSEA - IAD

1 stop9h 42mDelta

Deal found 12/17

$209

Wed 1/145:30 pmIAD - SEA

1 stop8h 00mSouthwest

Tue 1/206:05 amSEA - IAD

1 stop6h 45mSouthwest

Deal found 12/16

$219

Fri 2/275:55 pmIAD - SEA

Nonstop6h 01mUnited Airlines

Mon 3/212:43 pmSEA - IAD

1 stop7h 38mUnited Airlines

Deal found 12/17

$219

Wed 1/287:30 amIAD - SEA

Nonstop5h 59mDelta

Wed 2/47:10 amSEA - IAD

1 stop8h 59mDelta

Deal found 12/17

$209

Fri 1/307:30 amIAD - SEA

Nonstop5h 59mDelta

Fri 2/612:00 pmSEA - IAD

1 stop8h 57mDelta

Deal found 12/16

$209

Wed 2/2512:23 pmIAD - SEA

1 stop10h 37mDelta

Fri 3/63:20 pmSEA - IAD

Nonstop4h 50mDelta

Deal found 12/17

$209

Thu 1/227:00 amIAD - SEA

1 stop10h 45mDelta

Sun 1/253:20 pmSEA - IAD

Nonstop4h 50mDelta

Deal found 12/15

$209

Wed 2/47:30 amIAD - SEA

Nonstop5h 59mDelta

Sun 2/86:05 amSEA - IAD

1 stop7h 41mDelta

Deal found 12/17

$209

Wed 1/146:00 amIAD - SEA

1 stop7h 42mDelta

Fri 1/2311:10 pmSEA - IAD

1 stop9h 39mDelta

Deal found 12/17

$219

Sat 1/315:27 pmIAD - SEA

1 stop7h 22mDelta

Wed 2/1112:00 pmSEA - IAD

1 stop8h 57mDelta

Deal found 12/17

$219

Fri 3/1312:12 pmIAD - SEA

1 stop9h 12mDelta

Tue 3/1710:59 pmSEA - IAD

1 stop10h 40mDelta

Deal found 12/16

$219

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

Tue 1/65:55 pmIAD - SEA

Nonstop6h 02mUnited Airlines

Tue 1/138:10 amSEA - IAD

Nonstop5h 06mUnited Airlines

Deal found 12/16

$216

Wed 1/77:30 amIAD - SEA

Nonstop5h 59mDelta

Tue 1/1311:10 pmSEA - IAD

1 stop9h 39mDelta

Deal found 12/16

$209

Thu 1/85:17 pmIAD - SEA

1 stop8h 26mUnited Airlines

Sun 1/117:00 amSEA - IAD

1 stop7h 35mUnited Airlines

Deal found 12/16

$233

Fri 1/95:55 pmIAD - SEA

Nonstop6h 02mUnited Airlines

Sun 1/118:10 amSEA - IAD

Nonstop5h 06mUnited Airlines

Deal found 12/15

$235

Sat 1/107:30 amIAD - SEA

Nonstop5h 59mDelta

Sat 1/176:15 amSEA - IAD

1 stop10h 09mDelta

Deal found 12/16

$210

Wed 1/146:00 amIAD - SEA

1 stop7h 42mDelta

Wed 1/2112:00 pmSEA - IAD

1 stop8h 57mDelta

Deal found 12/17

$219

Wed 1/142:10 pmIAD - SEA

1 stop10h 02mUnited Airlines

Sun 1/188:10 amSEA - IAD

Nonstop5h 06mUnited Airlines

Deal found 12/15

$228

Fri 1/165:55 pmIAD - SEA

Nonstop6h 02mUnited Airlines

Fri 1/238:10 amSEA - IAD

Nonstop5h 06mUnited Airlines

Deal found 12/17

$218

Sat 1/171:08 pmIAD - SEA

1 stop10h 37mAmerican Airlines

Mon 1/199:45 pmSEA - IAD

1 stop10h 13mAmerican Airlines

Deal found 12/17

$224

Fri 1/306:04 pmIAD - SEA

Nonstop6h 04mHawaiian Airlines

Fri 2/68:30 amSEA - IAD

Nonstop4h 56mHawaiian Airlines

Deal found 12/16

$230

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 December 18, 2025.

Thu 1/85:17 pmIAD - SEA

1 stop8h 26mUnited Airlines

Deal found 12/17

$125

Mon 1/57:06 pmIAD - SEA

2 stops25h 45mFrontier

Deal found 12/15

$127

Sat 1/172:58 pmIAD - SEA

3 stops23h 11mMultiple Airlines

Deal found 12/17

$129

Sun 2/1512:38 pmIAD - SEA

1 stop9h 22mDelta

Deal found 12/17

$130

Sun 3/16:20 pmIAD - SEA

1 stop18h 08mAlaska Airlines

Deal found 12/16

$134

Wed 1/146:00 amIAD - SEA

3 stops32h 54mMultiple Airlines

Deal found 12/17

$135

Sat 1/179:03 pmIAD - SEA

2 stops41h 06mFrontier

Deal found 12/17

$136

Wed 1/146:00 amIAD - SEA

2 stops32h 54mFrontier

Deal found 12/15

$137

Fri 1/165:55 pmIAD - SEA

Nonstop6h 02mUnited Airlines

Deal found 12/17

$139

Sat 2/1411:37 amIAD - SEA

2 stops26h 18mFrontier

Deal found 12/16

$140

Find flight deals from Dulles Intl to Seattle

Most accurate provider	eDreams 3 stars
Most trusted provider	eDreams 3 stars
Round-trip from	$209 (Delta)
One-way from	$125 (United Airlines)
Popular in	June
Cheapest in	January
Average price	$453
Good round-trip deal	$343 or less
Good one-way deal	$251 or less

Provider with most accurate pricing for Washington, D.C. Dulles Intl-Seattle/Tacoma Intl flight deals.

Search Deals

Provider most trusted by Cheapflights users for Washington, D.C. Dulles Intl-Seattle/Tacoma Intl flights.

Search Deals

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

Search Deals

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

Search Deals

Highest demand for flights based on searches. 7% potential increase in price ($34 potential increase over avg. RT price).

Search Deals

Cheapest flight prices on average. 1% potential price decrease ($6 potential savings vs. average RT price).

Search Deals

Average for round-trip flights in December 2025

Search Deals

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

Search Deals

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

Search Deals

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 1/14

7:30 am-10:29 am

Nonstop5h 59m

Seattle/Tacoma Intl

Tue 1/20

11:10 pm-11:52 am

1 stop9h 42m

$209

Washington, D.C.Seattle

IAD - SEA

IADSEA

Washington, D.C. Dulles Intl

Wed 1/28

7:30 am-10:29 am

Nonstop5h 59m

Seattle/Tacoma Intl

Wed 2/4

7:10 am-7:09 pm

1 stop8h 59m

$209

Washington, D.C.Seattle

IAD - SEA

IADSEA

Washington, D.C. Dulles Intl

Fri 1/30

7:30 am-10:29 am

Nonstop5h 59m

Seattle/Tacoma Intl

Fri 2/6

12:00 pm-11:57 pm

1 stop8h 57m

$209

Washington, D.C.Seattle

IAD - SEA

IADSEA

Washington, D.C. Dulles Intl

Wed 2/25

12:23 pm-8:00 pm

1 stop10h 37m

Seattle/Tacoma Intl

Fri 3/6

3:20 pm-11:10 pm

Nonstop4h 50m

$209

Washington, D.C.Seattle

IAD - SEA

IADSEA

Washington, D.C. Dulles Intl

Thu 1/22

7:00 am-2:45 pm

1 stop10h 45m

Seattle/Tacoma Intl

Sun 1/25

3:20 pm-11:10 pm

Nonstop4h 50m

$209

Washington, D.C.Seattle

IAD - SEA

IADSEA

Washington, D.C. Dulles Intl

Wed 2/4

7:30 am-10:29 am

Nonstop5h 59m

Seattle/Tacoma Intl

Sun 2/8

6:05 am-4:46 pm

1 stop7h 41m

$209

Washington, D.C.Seattle

IAD - SEA

IADSEA

Washington, D.C. Dulles Intl

Wed 1/14

5:30 pm-10:30 pm

1 stop8h 00m

Seattle/Tacoma Intl

Tue 1/20

6:05 am-3:50 pm

1 stop6h 45m

$219

Washington, D.C.Seattle

IAD - SEA

IADSEA

Washington, D.C. Dulles Intl

Fri 2/27

5:55 pm-8:56 pm

Nonstop6h 01m

Seattle/Tacoma Intl

Mon 3/2

12:43 pm-11:21 pm

1 stop7h 38m

$219

Washington, D.C.Seattle

IAD - SEA

IADSEA

Washington, D.C. Dulles Intl

Wed 1/14

6:00 am-10:42 am

1 stop7h 42m

Seattle/Tacoma Intl

Fri 1/23

11:10 pm-11:49 am

1 stop9h 39m

$219

Washington, D.C.Seattle

IAD - SEA

IADSEA

Washington, D.C. Dulles Intl

Sat 1/31

5:27 pm-9:49 pm

1 stop7h 22m

Seattle/Tacoma Intl

Wed 2/11

12:00 pm-11:57 pm

1 stop8h 57m

$219

Flights are sorted by cheapest round-trip flights first.

Deals found on 12/17

Showing 1-10 of 23 results

Compare providers for flights from Dulles Intl to Seattle

Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from Dulles Intl to Seattle in December.

Provider	Price Accuracy	Trust Score*
Expedia	Price Accuracy2 stars	Trust Score*3 stars
FlightHub	Price Accuracy3 stars	Trust Score*1 star
eDreams	Price Accuracy3 stars	Trust Score*3 stars
Cheapflightsfares	Price Accuracy3 stars	Trust Score*2 stars
Cheapfaremart	Price Accuracy-	Trust Score*1 star
CheapTicketsDeal	Price Accuracy3 stars	Trust 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 Washington, D.C. Dulles Intl Airport-Seattle flights, users find the pricing of eDreams to be most consistent on Cheapflights vs. eDreams Users can find the same prices on Washington, D.C. Dulles Intl Airport-Seattle flight deals on Cheapflights vs. eDreams >95% of the time. Price accuracy is based on data collected from Washington, D.C. Dulles Intl Airport-Seattle flight searches over the past month and is updated monthly.
Most trusted provider: When it comes to deals on Washington, D.C. Dulles Intl Airport-Seattle flights, Cheapflights users trust eDreams the most. eDreams 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 Washington, D.C. Dulles Intl Airport-Seattle flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

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

Prices

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 36 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, April is the cheapest month in which you can book a flight from Washington, D.C. Dulles Intl Airport to Seattle (average of $157). Flying from Washington, D.C. Dulles Intl Airport to Seattle in March is currently the most expensive (average of $270). 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 17% 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 Tuesday evenings when fares are most often at their lowest. Monday evenings flights should be avoided if possible as fares are typically the most expensive at this time.

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

Reviews of airlines servicing Seattle

See what other customers who have flown with Alaska Airlines, Delta, and Hawaiian Airlines 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

11,477 reviews

Reviews

1 / 20

10.0

Excellent

Anonymous,Dec 2025

SJC - SEA

The flight was great. Don’t have to make it better. Everything was OK.

Alaska Airlines

8.0

Very good

11,477 reviews

Alaska Airlines

8.0

Very good

11,477 reviews

Reviews

1 / 20

10.0

Excellent

Anonymous,Dec 2025

SJC - SEA

The flight was great. Don’t have to make it better. Everything was OK.

Delta

7.9

Good

8,005 reviews

Alaska Airlines

8.0

Very good

11,477 reviews

Reviews

1 / 20

10.0

Excellent

Anonymous,Dec 2025

SJC - SEA

The flight was great. Don’t have to make it better. Everything was OK.

Hawaiian Airlines

7.8

Good

2,820 reviews

Alaska Airlines

8.0

Very good

11,477 reviews

Reviews

1 / 20

10.0

Excellent

Anonymous,Dec 2025

SJC - SEA

The flight was great. Don’t have to make it better. Everything was OK.

United Airlines

7.4

Good

9,091 reviews

Alaska Airlines

8.0

Very good

11,477 reviews

Reviews

1 / 20

10.0

Excellent

Anonymous,Dec 2025

SJC - SEA

The flight was great. Don’t have to make it better. Everything was OK.

American Airlines

7.2

Good

11,054 reviews

Alaska Airlines

8.0

Very good

11,477 reviews

Reviews

1 / 20

10.0

Excellent

Anonymous,Dec 2025

SJC - SEA

The flight was great. Don’t have to make it better. Everything was OK.

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. 6 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 4 inbound flights from Washington, D.C. Dulles Intl per day.
How long is the flight from Washington, D.C. Dulles Intl Airport to Seattle?
There are many flights that can get you from Washington, D.C. Dulles Intl Airport to Seattle in 5h 59m. Fly via Delta to get the fastest option. Airlines will cover a distance of 2299 mi. Generally, flights for this route are nonstop.
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 $111. Other airlines that can offer you cheap pricing are Hawaiian Airlines, from $143, and Delta, from $158. Frontier is currently priced 72% 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 Frontier, which is currently one of the cheapest options available, starting at $116. Delta flights start at $129 while deals on Alaska Airlines start at $138 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 ITA Airways (100%), United Airlines (87%) and Austrian Airlines (78%).
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 $119. On average you can expect to pay $1,192. The most popular route, (Washington, D.C. Dulles Intl - Seattle/Tacoma Intl), can usually be booked for $199.
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, April is the cheapest month in which you can book a flight from Washington, D.C. Dulles Intl Airport to Seattle (average of $157). Flying from Washington, D.C. Dulles Intl Airport to Seattle in March is currently the most expensive (average of $270). 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 Dulles Intl to Seattle

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Other flights to Seattle

Top 6 airlines flying from Dulles Intl to Seattle

Airline	Cheapest	Average	Flexibility	On-time
Frontier	Cheapest$111	Average$258	FlexibilityNo cancel fee	On-time62%
Hawaiian Airlines	Cheapest$149	Average$393	FlexibilityNo cancel fee	On-time85%
Delta	Cheapest$179	Average$376	FlexibilityNo cancel fee	On-timeN/A
Alaska Airlines	Cheapest$264	Average$430	FlexibilityNo cancel fee	On-time75%
United Airlines	Cheapest$274	Average$451	FlexibilityNo cancel fee	On-time69%
American Airlines	Cheapest$336	Average$527	FlexibilityNo cancel fee	On-time71%

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$125+ 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 1/8. Fares are subject to change and may not be available on all flights or dates of travel.

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Cheapflights Tip: The best prices from Washington, D.C. Dulles Intl to Seattle/Tacoma Intl are usually found in January or February, booked 36 days in advance, depart on a Tuesday or Wednesday and return on a Thursday

Cheap 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 December 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 December 18, 2025.

Find flight deals from Dulles Intl to Seattle

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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.

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Best time to book a flight from Dulles Intl to Seattle

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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?

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?

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

What’s the top layover airport for flights from Washington, D.C. Dulles Intl Airport to Seattle?

What’s the cheapest layover airport for flights from Washington, D.C. Dulles Intl Airport to Seattle?

What’s the fastest layover option from Washington, D.C. Dulles Intl Airport to Seattle?

Which airport typically offers the quickest layover for flights from Washington, D.C. Dulles Intl Airport to Seattle?

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

AI-powered summary based on content written by travel experts. AI can make mistakes.

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

Reviews of airlines servicing Seattle

See what other customers who have flown with Alaska Airlines, Delta, and Hawaiian Airlines 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?

How long is the flight from Washington, D.C. Dulles Intl Airport to Seattle?

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?

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

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

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Alternative routes for Dulles Intl to Seattle

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Top 6 airlines flying from Dulles Intl 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 December 18, 2025.