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Cheap flights from Philadelphia (PHL) to Seattle (BFI)

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How to find the cheapest flight from Philadelphia (PHL) to Seattle (BFI)

How to find the cheapest flight from Philadelphia (PHL) to Seattle (BFI)
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How to find the cheapest flight from Philadelphia (PHL) to Seattle (BFI)
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How to find the cheapest flight from Philadelphia (PHL) to Seattle (BFI)
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Cheap flights from Philadelphia to Seattle in April , May 2026

28 Apr - 27 May $ 696.00
PHL
Philadelphia
Frontier Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
3 STOPS
PHL
Philadelphia
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28 Apr - 26 May $ 743.00
PHL
Philadelphia
Frontier Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
PHL
Philadelphia
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29 Apr - 26 May $ 754.00
PHL
Philadelphia
Frontier Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
PHL
Philadelphia
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Last minute flights from Philadelphia to Seattle

28 Apr - 01 May $ 745.00
PHL
Philadelphia
Frontier Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
3 STOPS
PHL
Philadelphia
Pick dates
28 Apr - 01 May $ 761.00
PHL
Philadelphia
Frontier Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
3 STOPS
PHL
Philadelphia
Pick dates
28 Apr - 30 Apr $ 775.00
PHL
Philadelphia
Frontier Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
PHL
Philadelphia
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One-way flights to Seattle from Philadelphia

8:36 PM - 2:45 PM
Air Excursions
2 Stops
21h 59m
PHL - BFI
$ 323
Kiwi
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8:31 PM - 2:45 PM
Air Excursions
2 Stops
22h 4m
PHL - BFI
$ 335
Kiwi
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8:41 PM - 2:45 PM
Air Excursions
2 Stops
21h 54m
PHL - BFI
$ 428
Kiwi
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How to find the cheapest flight from Philadelphia (PHL) to Seattle (BFI)

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How to find the cheapest flight from Philadelphia (PHL) to Seattle (BFI)
Some placeholder content for the first accordion panel. This panel is shown by default, thanks to the .show class.
How to find the cheapest flight from Philadelphia (PHL) to Seattle (BFI)
Some placeholder content for the first accordion panel. This panel is shown by default, thanks to the .show class.