BOS to SEA from $273 in economy – flightdeals.net

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United Airlines

UAUnited Airlines

Round Trip•Economy

Logan International Airport

Boston, United States

Seattle–Tacoma International Airport

Seattle / Tacoma, United States

$464 USD

-41%$273 USD

Verified about 6 hours ago

July 2026

Mon

Tue

Wed

Thu

Fri

Sat

Sun

29$320 30$341 1$461 2$420 3$310 4$340 5$527 6$609 7$477 8$478 9$426 10$465 11$402 12$506 13$484 14$416 15$488 16$545 17$509 18$468 19$595 20$406 21$418 22$442 23$535 24$528 25$537 26$655 27$513 28$383 29$404 30$500 31$503 1$585 2$460

Limited Availability

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

Tuesday, July 21st, 2026

2 round-trip options

Returning

Sun, Jul 26, 2026•5 Day Trip

$570 USD

Returning

Tue, Aug 4, 2026•14 Day Trip

$418 USD