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

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0 Children (2~11)
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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 July , August 2026

27 Jul - 26 Aug $ 850.00
PHL
Philadelphia
Frontier Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
PHL
Philadelphia
Pick dates
27 Jul - 14 Aug $ 850.00
PHL
Philadelphia
Frontier Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
PHL
Philadelphia
Pick dates
27 Jul - 28 Aug $ 850.00
PHL
Philadelphia
Frontier Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
PHL
Philadelphia
Pick dates

Last minute flights from Philadelphia to Seattle

27 Jul - 31 Jul $ 1,029.00
PHL
Philadelphia
Frontier Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
PHL
Philadelphia
Pick dates
27 Jul - 31 Jul $ 1,035.00
PHL
Philadelphia
Frontier Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
PHL
Philadelphia
Pick dates
30 Jul - 31 Jul $ 1,060.00
PHL
Philadelphia
Frontier Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
PHL
Philadelphia
Pick dates

One-way flights to Seattle from Philadelphia

11:06 AM - 6:45 AM
Air Excursions
2 Stops
23h 29m
PHL - BFI
$ 527
Kiwi
Pick dates
11:06 AM - 9:25 PM
Air Excursions
2 Stops
14h 9m
PHL - BFI
$ 529
Kiwi
Pick dates
11:06 AM - 9:25 PM
Air Excursions
2 Stops
14h 9m
PHL - BFI
$ 560
Kiwi
Pick dates

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

Related info for your journey
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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.