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Cheap flights from St Louis (STL) to Seattle (BFI)

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0 Children (2~11)
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How to find the cheapest flight from St Louis (STL) to Seattle (BFI)

How to find the cheapest flight from St Louis (STL) to Seattle (BFI)
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How to find the cheapest flight from St Louis (STL) to Seattle (BFI)
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How to find the cheapest flight from St Louis (STL) to Seattle (BFI)
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Cheap flights from St Louis to Seattle in July , August 2026

31 Jul - 27 Aug $ 859.00
STL
St Louis
Frontier Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
STL
St Louis
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28 Jul - 27 Aug $ 946.00
STL
St Louis
Frontier Airlines
3 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
STL
St Louis
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23 Jul - 27 Aug $ 963.00
STL
St Louis
Frontier Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
STL
St Louis
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Last minute flights from St Louis to Seattle

28 Jul - 01 Aug $ 1,295.00
STL
St Louis
Frontier Airlines
3 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
3 STOPS
STL
St Louis
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23 Jul - 01 Aug $ 1,312.00
STL
St Louis
Frontier Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
3 STOPS
STL
St Louis
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23 Jul - 01 Aug $ 1,408.00
STL
St Louis
Frontier Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
3 STOPS
STL
St Louis
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One-way flights to Seattle from St Louis

8:08 PM - 9:35 AM
Air Excursions
2 Stops
40h 17m
STL - BFI
$ 561
Kiwi
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3:41 PM - 6:45 PM
Air Excursions
3 Stops
29h 54m
STL - BFI
$ 642
Kiwi
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7:10 PM - 8:25 PM
Air Excursions
2 Stops
28h 5m
STL - BFI
$ 659
Kiwi
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How to find the cheapest flight from St Louis (STL) to Seattle (BFI)

Related info for your journey
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How to find the cheapest flight from St Louis (STL) 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 St Louis (STL) to Seattle (BFI)
Some placeholder content for the first accordion panel. This panel is shown by default, thanks to the .show class.