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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 August , September 2026

23 Aug - 14 Sep $ 374.00
STL
St Louis
Frontier Airlines
1 STOPS
PHL
Philadelphia
PHL
Philadelphia
Frontier Airlines
1 STOPS
STL
St Louis
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21 Aug - 10 Sep $ 598.00
STL
St Louis
United Airlines
1 STOPS
PHL
Philadelphia
PHL
Philadelphia
United Airlines
1 STOPS
STL
St Louis
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21 Aug - 10 Sep $ 598.00
STL
St Louis
United Airlines
1 STOPS
PHL
Philadelphia
PHL
Philadelphia
United Airlines
1 STOPS
STL
St Louis
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Last minute flights from St Louis to Philadelphia

28 Aug - 31 Aug $ 655.00
STL
St Louis
United Airlines
1 STOPS
PHL
Philadelphia
PHL
Philadelphia
United Airlines
1 STOPS
STL
St Louis
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27 Aug - 31 Aug $ 655.00
STL
St Louis
United Airlines
1 STOPS
PHL
Philadelphia
PHL
Philadelphia
United Airlines
1 STOPS
STL
St Louis
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21 Aug - 31 Aug $ 657.00
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

6:17 PM - 5:05 AM
Frontier Airlines
1 Stops
11h 58m
STL - PHL
$ 196
Kiwi
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5:02 PM - 6:58 AM
Frontier Airlines
1 Stops
15h 33m
STL - PHL
$ 196
Kiwi
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8:40 AM - 1:05 PM
United Airlines
1 Stops
4h 41m
STL - PHL
$ 294
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.