$149 Cheap Delta flights Washington (IAD) to Seattle (SEA)

View $149 flight on Wed, Sep 10, 2025Opens in a new window

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$149 Cheap Delta flights Washington (IAD) to Seattle (SEA)

Prices were available within the past 7 days and start at $149 for one-way flights and $257 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Delta
Wed, Aug 27 - Sat, Aug 30
IAD
Washington
SEA
Seattle
$257 Roundtrip, just found
$257
Roundtrip
just found
Select Delta flight, departing Wed, Aug 27 from Washington to Seattle, returning Sat, Aug 30, priced at $257 just found
Flights from Washington (IAD) to Seattle (SEA)
Origin airport
Washington Dulles Intl.
Destination airport
Seattle - Tacoma Intl.
Airlines serving
Alaska Airlines, American Airlines, Delta, Frontier Airlines, Hawaiian Airlines, Southwest Airlines, Sun Country Airlines, United
Popular airline
Alaska Airlines
Distance
2299 mi
Average flight time
2 hours 48 mins

Frequently asked questions

How much is a Delta Air Lines flight from Washington Dulles Intl. Airport (IAD) to Seattle - Tacoma Intl. Airport (SEA)?
You'll find budget-friendly return Delta Air Lines flights from $257 from IAD to SEA by organizing your results from "Price (lowest to highest)" on Expedia. Or search for bargains from $149 for a one-way journey.**These prices were available on Expedia within the past 7 days, for flights departing within the next year. Prices and availability are subject to change. Additional terms apply.
What is the cheapest month to fly from IAD to SEA with Delta Air Lines?
Delta Air Lines flights to Seattle tend to be more affordable in the quieter months of January and February. Whether you're after a one-way or round-trip ticket, you could find a better deal then.
What is the cheapest time to book flights from Washington Dulles Intl. Airport (IAD) to Seattle - Tacoma Intl. Airport (SEA) with Delta Air Lines?
Search for cheap Delta Air Lines flights from Washington Dulles Intl. Airport (IAD) to Seattle - Tacoma Intl. Airport (SEA) one to three months ahead of your departure date. Travelers who book domestic flights 34 to 86 days in advance can save 25% compared to those who book just 6 to 12 days ahead. Regardless of fare type and journey, the ideal day to book a domestic flight is usually Sunday and the most expensive tends to be Monday. Passengers who book on a Sunday can save 6% on average compared to those who book their travel on a Monday.**Ideal booking window recommendation is based on average round-trip ticket prices for January through November for 2024. Best day of the week to book recommendation is based on average round-trip ticket prices for January through October 2024. All data sourced from ARC's global airline sales database.
Does Delta Air Lines fly nonstop from Washington Dulles Intl. Airport (IAD) to Seattle - Tacoma Intl. Airport (SEA)?
Delta Air Lines offers direct flights from Washington Dulles Intl. Airport (IAD) to Seattle - Tacoma Intl. Airport (SEA), with 7 weekly departures. Just choose the "Nonstop" and "Airline" filters during your search on Expedia to find all direct Delta Air Lines flights to SEA.
How long does it take to fly from IAD to SEA with Delta Air Lines?
From wheels-up to touchdown, a nonstop Delta Air Lines flight from Washington Dulles Intl. Airport (IAD) to Seattle - Tacoma Intl. Airport (SEA) takes around 6h 1m.
What is the earliest Delta Air Lines flight from IAD to SEA?
Setting off from IAD at 4:05PM UTC-5, the first Delta Air Lines flight to SEA lands at 7:06PM UTC-8. Traveling earlier in the day means you'll be less likely to encounter cancellations or delays.* Not a morning person? The last Delta Air Lines flight from IAD to SEA departs at 4:05PM UTC-5 and touches down at 7:06PM UTC-8.*Most reliable time of the day recommendation is based on January through August 2024 flight status data sourced from OAG's global flight data platform.
What airports does Delta Air Lines fly into in Seattle?
Delta Air Lines flights from Washington Dulles Intl. Airport (IAD) to Seattle come in to land at Seattle - Tacoma Intl. Airport (SEA). This is the main gateway to this destination.
Why fly with Delta Air Lines from IAD to SEA?
Flying from IAD to SEA with Delta Air Lines comes with a range of perks, such as a rewarding loyalty program and an excellent in-flight experience. Plus, when you book through Expedia, One Key™ members can earn OneKeyCash™* to use on select future travel purchases. That's in addition to the Delta SkyMiles points you can earn with Delta Air Lines.*OneKeyCash™ disclaimer - OneKeyCash™ is not redeemable for cash and can only be used on Expedia, Hotels.com and Vrbo.
What type of plane does Delta Air Lines fly from Washington Dulles Intl. Airport (IAD) to Seattle - Tacoma Intl. Airport (SEA)?
Delta Air Lines typically uses Airbus A220-300 planes for journeys from Washington Dulles Intl. Airport (IAD) to Seattle - Tacoma Intl. Airport (SEA). Keep in mind that aircraft type can differ depending on operational demands, so the plane you board might be different on your travel date.
Can I change or cancel my Delta Air Lines flight from Washington Dulles Intl. Airport (IAD) to Seattle - Tacoma Intl. Airport (SEA)?
Changes are typically free within 24 hours of making your booking, but your airline may charge a fee after that time. For further details about modifying your flights, check out your "Trips," select your flight and click on "Manage Booking." If you want the freedom to update your itinerary without additional costs, check the "Changes included" or "No cancel fee" filter when organizing your next adventure.
*Available to One Key members.