Cheapest return flights from St. Louis to Frankfurt in September from 809€

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

Return flights

21 Sep - 08 Oct Frontier Airlines
26 Sep - 18 Oct Frontier Airlines
20 Sep - 27 Sep Frontier Airlines
24 Sep - 18 Oct Frontier Airlines
17 Sep - 03 Oct Frontier Airlines
19 Sep - 26 Sep Frontier Airlines
21 Sep - 08 Oct Lufthansa direct
17 Sep - 03 Oct Lufthansa direct
17 Sep - 23 Sep United
19 Sep - 26 Sep Lufthansa direct

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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