Cheap flights from Boston to Eastside

View AU$166 flight on Wed, 8 Oct. 2025Opens in a new window

Popular airlines from Boston to Eastside

  • American Airlines

    American Airlines

  • Alaska Airlines

    Alaska Airlines

  • Delta

    Delta

  • United

    United

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Cheap Flights from Boston (BOS) to Eastside (SEA)

Prices were available within the past 7 days for one-way flights and round trip tickets for the period specified. Prices and availability are subject to change. Additional terms apply.

Alaska Airlines
Wed, 8 Oct. - Tue, 14 Oct.
BOS
Boston
SEA
Seattle
AU$331 Return, found 4 days ago
AU$331
Return
found 4 days ago
Select Alaska Airlines flight, departing Wed, 8 Oct. from Boston to Seattle, returning Tue, 14 Oct., priced at AU$331 found 4 days ago
Delta
Wed, 8 Oct. - Tue, 14 Oct.
BOS
Boston
SEA
Seattle
AU$332 Return, found 4 days ago
AU$332
Return
found 4 days ago
Select Delta flight, departing Wed, 8 Oct. from Boston to Seattle, returning Tue, 14 Oct., priced at AU$332 found 4 days ago
Alaska Airlines
Sat, 4 Oct. - Sat, 11 Oct.
BOS
Boston
SEA
Seattle
AU$335 Return, found 7 hours ago
AU$335
Return
found 7 hours ago
Select Alaska Airlines flight, departing Sat, 4 Oct. from Boston to Seattle, returning Sat, 11 Oct., priced at AU$335 found 7 hours ago
Delta
Sat, 4 Oct. - Sat, 11 Oct.
BOS
Boston
SEA
Seattle
AU$336 Return, found 7 hours ago
AU$336
Return
found 7 hours ago
Select Delta flight, departing Sat, 4 Oct. from Boston to Seattle, returning Sat, 11 Oct., priced at AU$336 found 7 hours ago
American Airlines
Wed, 8 Oct. - Tue, 14 Oct.
BOS
Boston
SEA
Seattle
AU$362 Return, found 4 days ago
AU$362
Return
found 4 days ago
Select American Airlines flight, departing Wed, 8 Oct. from Boston to Seattle, returning Tue, 14 Oct., priced at AU$362 found 4 days ago
United
Wed, 8 Oct. - Tue, 14 Oct.
BOS
Boston
SEA
Seattle
AU$431 Return, found 4 days ago
AU$431
Return
found 4 days ago
Select United flight, departing Wed, 8 Oct. from Boston to Seattle, returning Tue, 14 Oct., priced at AU$431 found 4 days ago

Find the cheapest month to fly from Boston (BOS) to Seattle (SEA)

September is typically the cheapest month to fly

From AU$238 - AU$376 per traveller.

Graph displaying average flight prices per month

*Available to Expedia members.