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Cheap flights from St Louis (STL) to Philadelphia (PHL)

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1 Adults (11+)
0 Children (2~11)
0 Infants (0~2)
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How to find the cheapest flight from St Louis (STL) to Philadelphia (PHL)

How to find the cheapest flight from St Louis (STL) to Philadelphia (PHL)
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How to find the cheapest flight from St Louis (STL) to Philadelphia (PHL)
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How to find the cheapest flight from St Louis (STL) to Philadelphia (PHL)
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Cheap flights from St Louis to Philadelphia in March , April 2026

31 Mar - 16 Apr $ 159.00
STL
St Louis
Frontier Airlines
1 STOPS
PHL
Philadelphia
PHL
Philadelphia
Frontier Airlines
1 STOPS
STL
St Louis
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07 Mar - 08 Apr $ 951.00
STL
St Louis
Alaska Airlines
1 STOPS
PHL
Philadelphia
PHL
Philadelphia
Alaska Airlines
1 STOPS
STL
St Louis
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09 Mar - 08 Apr $ 953.00
STL
St Louis
Alaska Airlines
1 STOPS
PHL
Philadelphia
PHL
Philadelphia
Alaska Airlines
1 STOPS
STL
St Louis
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Last minute flights from St Louis to Philadelphia

24 Mar - 31 Mar $ 245.00
STL
St Louis
Frontier Airlines
1 STOPS
PHL
Philadelphia
PHL
Philadelphia
Frontier Airlines
1 STOPS
STL
St Louis
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07 Mar - 31 Mar $ 1,067.00
STL
St Louis
Alaska Airlines
1 STOPS
PHL
Philadelphia
PHL
Philadelphia
Alaska Airlines
1 STOPS
STL
St Louis
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09 Mar - 31 Mar $ 1,077.00
STL
St Louis
Alaska Airlines
1 STOPS
PHL
Philadelphia
PHL
Philadelphia
Alaska Airlines
1 STOPS
STL
St Louis
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One-way flights to Philadelphia from St Louis

11:27 AM - 7:59 PM
Frontier Airlines
1 Stops
9h 41m
STL - PHL
$ 70
Kiwi
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5:00 AM - 7:15 AM
United Airlines
1 Stops
4h 13m
STL - PHL
$ 409
Kiwi
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10:00 AM - 2:10 PM
United Airlines
1 Stops
6h 14m
STL - PHL
$ 419
Kiwi
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How to find the cheapest flight from St Louis (STL) to Philadelphia (PHL)

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