Seattle / Tacoma (SEA) to Washington (IAD) flight deal in economy from $255

United AirlinesUAUnited Airlines
Round Trip•Economy
United StatesSEA

Seattle–Tacoma International Airport

Seattle / Tacoma, United States
United StatesIAD

Washington Dulles International Airport

Washington, United States
$450 USD
-43%$255 USD
Verified 15 days ago
Rare Availability
9% of dates checked are available within 10% of the lowest price

Tuesday, December 22nd, 2026

8 round-trip options

Returning
Sun, Dec 27, 2026•5 Day Trip
$770 USD
Google Flights
Returning
Mon, Dec 28, 2026•6 Day Trip
$533 USD
Google Flights
Returning
Tue, Dec 29, 2026•7 Day Trip
$517 USD
Google Flights
Returning
Wed, Dec 30, 2026•8 Day Trip
$485 USD
Google Flights
Returning
Thu, Dec 31, 2026•9 Day Trip
$457 USD
Google Flights
Returning
Fri, Jan 1, 2027•10 Day Trip
$490 USD
Google Flights
Returning
Mon, Jan 4, 2027•13 Day Trip
$447 USD
Google Flights
Returning
Tue, Jan 5, 2027•14 Day Trip
$447 USD
Google Flights