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 13 days ago
Rare Availability
9% of dates checked are available within 10% of the lowest price

Sunday, August 9th, 2026

8 round-trip options

Returning
Fri, Aug 14, 2026•5 Day Trip
$549 USD
Google Flights
Returning
Sat, Aug 15, 2026•6 Day Trip
$491 USD
Google Flights
Returning
Sun, Aug 16, 2026•7 Day Trip
$481 USD
Google Flights
Returning
Mon, Aug 17, 2026•8 Day Trip
$481 USD
Google Flights
Returning
Tue, Aug 18, 2026•9 Day Trip
$486 USD
Google Flights
Returning
Thu, Aug 20, 2026•11 Day Trip
$463 USD
Google Flights
Returning
Fri, Aug 21, 2026•12 Day Trip
$431 USD
Google Flights
Returning
Sat, Aug 22, 2026•13 Day Trip
$421 USD
Google Flights