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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 January , February 2026

30 Jan - 18 Feb $ 269.00
STL
St Louis
Frontier Airlines
1 STOPS
PHL
Philadelphia
PHL
Philadelphia
Frontier Airlines
1 STOPS
STL
St Louis
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18 Jan - 10 Feb $ 941.00
STL
St Louis
Alaska Airlines
1 STOPS
PHL
Philadelphia
PHL
Philadelphia
Alaska Airlines
1 STOPS
STL
St Louis
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17 Jan - 10 Feb $ 1,167.00
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

30 Jan - 01 Feb $ 398.00
STL
St Louis
Frontier Airlines
1 STOPS
PHL
Philadelphia
PHL
Philadelphia
Frontier Airlines
1 STOPS
STL
St Louis
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30 Jan - 31 Jan $ 453.00
STL
St Louis
Frontier Airlines
1 STOPS
PHL
Philadelphia
PHL
Philadelphia
Frontier Airlines
1 STOPS
STL
St Louis
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21 Jan - 31 Jan $ 744.00
STL
St Louis
United Airlines
1 STOPS
PHL
Philadelphia
PHL
Philadelphia
United Airlines
1 STOPS
STL
St Louis
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One-way flights to Philadelphia from St Louis

11:18 AM - 5:15 PM
Frontier Airlines
1 Stops
7h 39m
STL - PHL
$ 199
Kiwi
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8:32 PM - 8:00 AM
Frontier Airlines
2 Stops
37h 5m
STL - PHL
$ 199
Kiwi
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6:30 AM - 8:56 AM
United Airlines
1 Stops
4h 37m
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.