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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 September , October 2026

30 Sep - 14 Oct $ 182.00
STL
St Louis
Frontier Airlines
1 STOPS
PHL
Philadelphia
PHL
Philadelphia
Frontier Airlines
1 STOPS
STL
St Louis
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18 Sep - 07 Oct $ 317.00
STL
St Louis
Frontier Airlines
1 STOPS
PHL
Philadelphia
PHL
Philadelphia
Frontier Airlines
1 STOPS
STL
St Louis
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17 Sep - 07 Oct $ 327.00
STL
St Louis
Frontier Airlines
1 STOPS
PHL
Philadelphia
PHL
Philadelphia
Frontier Airlines
1 STOPS
STL
St Louis
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Last minute flights from St Louis to Philadelphia

28 Sep - 30 Sep $ 366.00
STL
St Louis
Frontier Airlines
1 STOPS
PHL
Philadelphia
PHL
Philadelphia
Frontier Airlines
1 STOPS
STL
St Louis
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18 Sep - 30 Sep $ 387.00
STL
St Louis
Frontier Airlines
1 STOPS
PHL
Philadelphia
PHL
Philadelphia
Frontier Airlines
1 STOPS
STL
St Louis
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18 Sep - 30 Sep $ 387.00
STL
St Louis
Frontier Airlines
1 STOPS
PHL
Philadelphia
PHL
Philadelphia
Frontier Airlines
1 STOPS
STL
St Louis
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One-way flights to Philadelphia from St Louis

2:29 PM - 9:07 PM
Frontier Airlines
1 Stops
7h 49m
STL - PHL
$ 139
Kiwi
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2:29 PM - 9:07 PM
Frontier Airlines
1 Stops
7h 49m
STL - PHL
$ 180
Kiwi
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8:40 AM - 1:05 PM
United Airlines
1 Stops
4h 40m
STL - PHL
$ 304
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.