Flights Seattle → Boston — September 11, 2026

One way · Economy · 1 adult · price per person

The cheapest itinerary observed for Friday, September 11, 2026 on the Seattle–Boston route: 1 stop itinerary (2 flights) via Philadelphia International (PHL), from Seattle-Tacoma (SEA) to Boston Logan (BOS), first flight American Airlines AA2886, departs 10:45 PM, arrives 10:24 AM the next day, total travel time 8h 39m including layovers, flight time 6h 49m (layovers excluded), $295 per person. Fare as listed by Aviasales: carry-on bag included, checked bag not included, changes not allowed, non-refundable. Price found in an Aviasales search on September 8, 2026 and read by AirSource on September 10, 2026, 20:47 UTC: it is not guaranteed and is confirmed on Aviasales at booking time. The cheapest direct flight observed: Alaska Airlines AS214, from Seattle-Tacoma (SEA) to Boston Logan (BOS), departs 11:06 PM, arrives 7:39 AM the next day, direct, 5h 33m, $334 per person. Fare as listed by Aviasales: carry-on bag included, checked bag not included, changes not allowed, non-refundable.