SEA to BOS from $303 in economy – flightdeals.net

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United Airlines

UAUnited Airlines

Round Trip•Economy

Seattle–Tacoma International Airport

Seattle / Tacoma, United States

Logan International Airport

Boston, United States

$421 USD

-28%$303 USD

Verified 1 day ago

September 2026

Mon

Tue

Wed

Thu

Fri

Sat

Sun

31$332 1$303 2$303 3$354 4$332 5$303 6$332 7$361 8$303 9$303 10$361 11$325 12$303 13$332 14$332 15$303 16$303 17$361 18$332 19$303 20$332 21$332 22$303 23$303 24$361 25$332 26$303 27$332 28$332 29$303 30$415 1$411 2$361 3$332 4$332

Limited Availability

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

Saturday, September 12th, 2026

3 round-trip options

Returning

Sun, Sep 20, 2026•8 Day Trip

$332 USD

Returning

Tue, Sep 22, 2026•10 Day Trip

$303 USD

Returning

Wed, Sep 23, 2026•11 Day Trip

$303 USD