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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 February , March 2026

26 Feb - 07 Mar $ 836.00
STL
St Louis
Frontier Airlines
3 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
STL
St Louis
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08 Feb - 07 Mar $ 1,004.00
STL
St Louis
Frontier Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
STL
St Louis
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05 Feb - 07 Mar $ 1,027.00
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

26 Feb - 02 Mar $ 1,657.00
STL
St Louis
Frontier Airlines
3 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
3 STOPS
STL
St Louis
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26 Feb - 02 Mar $ 1,703.00
STL
St Louis
Frontier Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
3 STOPS
STL
St Louis
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08 Feb - 02 Mar $ 1,840.00
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

10:11 PM - 7:35 AM
Air Excursions
3 Stops
36h 14m
STL - BFI
$ 470
Kiwi
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9:32 PM - 2:45 PM
Air Excursions
2 Stops
20h 3m
STL - BFI
$ 631
Kiwi
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10:01 PM - 2:45 PM
Air Excursions
2 Stops
19h 34m
STL - BFI
$ 654
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.