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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 April , May 2026

22 Apr - 12 May $ 197.00
STL
St Louis
Frontier Airlines
1 STOPS
PHL
Philadelphia
PHL
Philadelphia
Frontier Airlines
2 STOPS
STL
St Louis
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10 Apr - 02 May $ 989.00
STL
St Louis
Alaska Airlines
1 STOPS
PHL
Philadelphia
PHL
Philadelphia
Alaska Airlines
1 STOPS
STL
St Louis
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11 Apr - 02 May $ 1,014.00
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

22 Apr - 01 May $ 180.00
STL
St Louis
Frontier Airlines
1 STOPS
PHL
Philadelphia
PHL
Philadelphia
Frontier Airlines
1 STOPS
STL
St Louis
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10 Apr - 30 Apr $ 1,022.00
STL
St Louis
Alaska Airlines
1 STOPS
PHL
Philadelphia
PHL
Philadelphia
Alaska Airlines
1 STOPS
STL
St Louis
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11 Apr - 30 Apr $ 1,028.00
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

8:23 PM - 6:00 AM
Frontier Airlines
1 Stops
10h 47m
STL - PHL
$ 70
Kiwi
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11:15 AM - 2:20 PM
United Airlines
1 Stops
5h 17m
STL - PHL
$ 346
Kiwi
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8:30 AM - 12:55 PM
United Airlines
1 Stops
4h 40m
STL - PHL
$ 347
Kiwi
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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)
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.