Cheapest return flights from St. Louis to Frankfurt in September from $720

AirHint found the following cheapest return flights from St. Louis (STL) to Frankfurt (FRA) in September 2025 (see full year).

Return flights

12 Sep - 19 Sep Frontier Airlines
14 Sep - 21 Sep Frontier Airlines
03 Sep - 10 Sep Frontier Airlines
21 Sep - 08 Oct Frontier Airlines
11 Sep - 18 Sep Spirit Airlines
15 Sep - 22 Sep Frontier Airlines
26 Sep - 18 Oct Frontier Airlines
05 Sep - 27 Sep Frontier Airlines
30 Sep - 21 Oct Scandinavian Airlines
23 Sep - 14 Oct Frontier Airlines
28 Sep - 19 Oct Frontier Airlines
30 Sep - 07 Oct Frontier Airlines
24 Sep - 15 Oct Frontier Airlines
17 Sep - 24 Sep Frontier Airlines
17 Sep - 03 Oct Hawaiian Airlines
03 Sep - 01 Oct Frontier Airlines
18 Sep - 09 Oct Frontier Airlines
02 Sep - 30 Sep Frontier Airlines
08 Sep - 11 Sep Air Canada
10 Sep - 19 Sep Aer Lingus

Also check the deals for one-way flights from St. Louis to Frankfurt in September.

Skyscanner

The deals are updated regularly. The prices may go up as tickets are purchased by other travellers. Only the cheapest flights are offered. Select a price to book and secure these cheap prices.

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