AirHint found the following cheapest return flights from Istanbul (IST) to Helsinki (HEL) in September 2025 (see full year).

Return flights

03 Sep - 06 Sep	Pegasus Airlines	direct
13 Sep - 17 Sep	Pegasus Airlines	direct
08 Sep - 10 Sep	Pegasus Airlines	direct
08 Sep - 13 Sep	Pegasus Airlines	direct
17 Sep - 20 Sep	Pegasus Airlines	direct
02 Sep - 09 Sep	Pegasus Airlines	direct
05 Sep - 07 Sep	Pegasus Airlines	direct
10 Sep - 16 Sep	Pegasus Airlines	direct
19 Sep - 29 Sep	airBaltic
12 Sep - 15 Sep	Pegasus Airlines	direct

Also check the deals for one-way flights from Istanbul to Helsinki 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.

Book a cheap hotel in Helsinki

Cheap car rent in Helsinki

Cheapest return flights from Istanbul to Helsinki in September from $180

Return flights