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

Return flights

22 Sep - 06 Oct	Condor
09 Sep - 23 Sep	Condor
16 Sep - 19 Sep	Spirit Airlines
02 Sep - 09 Sep	jetBlue
23 Sep - 03 Oct	Spirit Airlines
30 Sep - 07 Oct	Discover Airlines	direct
02 Sep - 05 Sep	Frontier Airlines
23 Sep - 03 Oct	United	direct
24 Sep - 01 Oct	Discover Airlines	direct
22 Sep - 29 Sep	Discover Airlines	direct
26 Sep - 03 Oct	United	direct
28 Sep - 05 Oct	Discover Airlines	direct
22 Sep - 06 Oct	Discover Airlines	direct
19 Sep - 23 Sep	Lufthansa	direct
09 Sep - 23 Sep	Discover Airlines	direct
04 Sep - 11 Sep	Lufthansa	direct
02 Sep - 09 Sep	Lufthansa	direct
16 Sep - 19 Sep	Discover Airlines	direct

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

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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Cheapest return flights from Philadelphia to Frankfurt in September from 502€

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