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

Return flights

10 Sep - 17 Sep	Ryanair
03 Sep - 17 Sep	Ryanair
06 Sep - 17 Sep	Ryanair
08 Sep - 15 Sep	Ryanair
08 Sep - 16 Sep	Turkish Airlines
05 Sep - 10 Sep	Ryanair
01 Sep - 17 Sep	Turkish Airlines
05 Sep - 19 Sep	Ryanair
04 Sep - 16 Sep	Turkish Airlines
03 Sep - 18 Sep	Ryanair
21 Sep - 11 Oct	Ryanair
22 Sep - 11 Oct	Ryanair
21 Sep - 11 Oct	MIAT Mongolian Airlines	direct
28 Sep - 15 Oct	SunExpress
13 Sep - 04 Oct	Ryanair
27 Sep - 04 Oct	Ryanair
29 Sep - 16 Oct	Pegasus Airlines
20 Sep - 01 Oct	Turkish Airlines
12 Sep - 01 Oct	MIAT Mongolian Airlines
30 Sep - 02 Oct	Air Serbia

Also check the deals for one-way flights from Frankfurt to Ulaanbaatar 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 Frankfurt to Ulaanbaatar in September from $611

Return flights