BOS to SEA from $303 in economy

UAUnited Airlines

Round Trip•Economy

BOS

Logan International Airport

Boston, United States

SEA

Seattle–Tacoma International Airport

Seattle / Tacoma, United States

$417 USD

-27%$303 USD

Verified 2 days ago

December 2026

Today

Mon

Tue

Wed

Thu

Fri

Sat

Sun

30$664 1$523 2$389 3$421 4$354 5$354 6$356 7$347 8$347 9$352 10$354 11$349 12$347 13$349 14$349 15$364 16$480 17$539 18$555 19$465 20$456 21$546 22$574 23$574 24$494 25$376 26$686 27$945 28$644 29$548 30$490 31$460 1$442 2$547 3$514

Limited Availability

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

Wednesday, December 9th, 2026

8 round-trip options

Returning

Mon, Dec 14, 2026•5 Day Trip

$354 USD

Google Flights

Returning

Tue, Dec 15, 2026•6 Day Trip

$352 USD

Google Flights

Returning

Wed, Dec 16, 2026•7 Day Trip

$395 USD

Google Flights

Returning

Thu, Dec 17, 2026•8 Day Trip

$499 USD

Google Flights

Returning

Sun, Dec 20, 2026•11 Day Trip

$382 USD

Google Flights

Returning

Mon, Dec 21, 2026•12 Day Trip

$359 USD

Google Flights

Returning

Tue, Dec 22, 2026•13 Day Trip

$393 USD

Google Flights

Returning

Wed, Dec 23, 2026•14 Day Trip

$504 USD

Google Flights

Boston (BOS) to Seattle / Tacoma (SEA) flight deal in economy from $303

Logan International Airport

Seattle–Tacoma International Airport

December 2026

Wednesday, December 9th, 2026