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

United AirlinesUAUnited Airlines
Round Trip•Economy
United StatesSEA

Seattle–Tacoma International Airport

Seattle / Tacoma, United States
United StatesBOS

Logan International Airport

Boston, United States
$421 USD
-28%$303 USD
Verified 1 day ago
Limited Availability
10% of dates checked are available within 10% of the lowest price

Thursday, August 20th, 2026

6 round-trip options

Returning
Tue, Aug 25, 2026•5 Day Trip
$332 USD
Google Flights
Returning
Wed, Aug 26, 2026•6 Day Trip
$332 USD
Google Flights
Returning
Thu, Aug 27, 2026•7 Day Trip
$361 USD
Google Flights
Returning
Fri, Aug 28, 2026•8 Day Trip
$361 USD
Google Flights
Returning
Sun, Aug 30, 2026•10 Day Trip
$361 USD
Google Flights
Returning
Thu, Sep 3, 2026•14 Day Trip
$383 USD
Google Flights