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

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0 Children (2~11)
0 Infants (0~2)
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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 December 2025 , January 2026

20 Dec - 29 Jan $ 1,038.00
STL
St Louis
Frontier Airlines
3 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
STL
St Louis
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23 Dec - 29 Jan $ 1,055.00
STL
St Louis
Frontier Airlines
3 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
STL
St Louis
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29 Dec - 29 Jan $ 1,139.00
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

23 Dec - 01 Jan $ 1,193.00
STL
St Louis
Frontier Airlines
3 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
3 STOPS
STL
St Louis
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20 Dec - 01 Jan $ 1,211.00
STL
St Louis
Frontier Airlines
3 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
3 STOPS
STL
St Louis
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23 Dec - 01 Jan $ 1,228.00
STL
St Louis
Frontier Airlines
3 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
3 STOPS
STL
St Louis
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One-way flights to Seattle from St Louis

7:43 PM - 5:45 PM
Air Excursions
3 Stops
24h 52m
STL - BFI
$ 623
Kiwi
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10:10 PM - 5:25 PM
Air Excursions
3 Stops
22h 5m
STL - BFI
$ 640
Kiwi
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10:10 PM - 2:45 PM
Air Excursions
3 Stops
19h 25m
STL - BFI
$ 713
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.