Cheap flights from Boston to Northwest Washington

View AU$145 flight on Sat, 15 Nov. 2025Opens in a new window

Popular airlines from Boston to Northwest Washington

  • Jetstar

    Jetstar

  • Qantas Airways

    Qantas Airways

  • Virgin Australia

    Virgin Australia

  • Scoot

    Scoot

  • American Airlines

    American Airlines

  • Emirates

    Emirates

  • United

    United

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Cheap Flights from Boston (BOS) to Northwest Washington (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.

American Airlines
Thu, 30 Oct. - Wed, 5 Nov.
BOS
Boston
SEA
Seattle
AU$290 Return, found 2 days ago
AU$290
Return
found 2 days ago
Select American Airlines flight, departing Thu, 30 Oct. from Boston to Seattle, returning Wed, 5 Nov., priced at AU$290 found 2 days ago
Alaska Airlines
Sat, 13 Sep. - Sat, 20 Sep.
BOS
Boston
SEA
Seattle
AU$330 Return, found 17 hours ago
AU$330
Return
found 17 hours ago
Select Alaska Airlines flight, departing Sat, 13 Sep. from Boston to Seattle, returning Sat, 20 Sep., priced at AU$330 found 17 hours ago
Delta
Sat, 13 Sep. - Sat, 20 Sep.
BOS
Boston
SEA
Seattle
AU$331 Return, found 17 hours ago
AU$331
Return
found 17 hours ago
Select Delta flight, departing Sat, 13 Sep. from Boston to Seattle, returning Sat, 20 Sep., priced at AU$331 found 17 hours ago
Alaska Airlines
Sat, 4 Oct. - Sat, 11 Oct.
BOS
Boston
SEA
Seattle
AU$335 Return, found 5 days ago
AU$335
Return
found 5 days ago
Select Alaska Airlines flight, departing Sat, 4 Oct. from Boston to Seattle, returning Sat, 11 Oct., priced at AU$335 found 5 days ago
Delta
Sat, 4 Oct. - Sat, 11 Oct.
BOS
Boston
SEA
Seattle
AU$336 Return, found 5 days ago
AU$336
Return
found 5 days ago
Select Delta flight, departing Sat, 4 Oct. from Boston to Seattle, returning Sat, 11 Oct., priced at AU$336 found 5 days ago
United
Thu, 30 Oct. - Wed, 5 Nov.
BOS
Boston
SEA
Seattle
AU$382 Return, found 2 days ago
AU$382
Return
found 2 days ago
Select United flight, departing Thu, 30 Oct. from Boston to Seattle, returning Wed, 5 Nov., priced at AU$382 found 2 days ago
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