St. Louis Gateway Arch
STL
Saint Louis
Philadelphia skyline with City Hall
PHL
Philadelphia

Saint Louis → Philadelphia

Frontier Airlines · Round Trip · Nonstop

$356$412

per person · round trip

Book This Deal

Flight Details

Cabin
Economy
Departs
Jun 25, 2026
Returns
Jul 5, 2026

Price History

Avg: $384
Low: $356
High: $412
Current price is the lowest recorded!
$340$370$400$430Mar 29Apr 6

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