SEA to IAD from $255 in economy

ASAlaska Airlines, Inc.

Round Trip•Economy

SEA

Seattle–Tacoma International Airport

Seattle / Tacoma, United States

IAD

Washington Dulles International Airport

Washington, United States

$458 USD

-44%$255 USD

Verified about 4 hours ago

December 2026

Today

Mon

Tue

Wed

Thu

Fri

Sat

Sun

30$778 1$497 2$447 3$447 4$447 5$447 6$447 7$447 8$447 9$447 10$447 11$447 12$497 13$497 14$497 15$497 16$542 17$577 18$652 19$802 20$652 21$552 22$497 23$497 24$447 25$447 26$497 27$542 28$497 29$447 30$447 31$497 1$497 2$542 3$542

Extremely Rare Availability

4% of dates checked are available within 10% of the lowest price

Wednesday, December 16th, 2026

7 round-trip options

Returning

Mon, Dec 21, 2026•5 Day Trip

$542 USD

Google Flights

Returning

Wed, Dec 23, 2026•7 Day Trip

$542 USD

Google Flights

Returning

Sat, Dec 26, 2026•10 Day Trip

$602 USD

Google Flights

Returning

Sun, Dec 27, 2026•11 Day Trip

$602 USD

Google Flights

Returning

Mon, Dec 28, 2026•12 Day Trip

$542 USD

Google Flights

Returning

Tue, Dec 29, 2026•13 Day Trip

$542 USD

Google Flights

Returning

Wed, Dec 30, 2026•14 Day Trip

$542 USD

Google Flights

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

Seattle–Tacoma International Airport

Washington Dulles International Airport

December 2026

Wednesday, December 16th, 2026