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

Return flights

30 Sep - 04 Oct	Ryanair
30 Sep - 21 Oct	Aegean Airlines
22 Sep - 29 Sep	Ryanair
21 Sep - 23 Sep	Aegean Airlines
26 Sep - 05 Oct	Ryanair
22 Sep - 23 Sep	Air Serbia
27 Sep - 29 Sep	Ryanair
19 Sep - 23 Sep	Ryanair
26 Sep - 29 Sep	Ryanair
26 Sep - 30 Sep	Ryanair
25 Sep - 29 Sep	Air Serbia
22 Sep - 25 Sep	Air Serbia
22 Sep - 24 Sep	Air Serbia
30 Sep - 07 Oct	Ryanair
30 Sep - 21 Oct	Turkish Airlines	direct
30 Sep - 01 Oct	Aegean Airlines
21 Sep - 06 Oct	SKY express
28 Sep - 15 Oct	SKY express
21 Sep - 08 Oct	SKY express
21 Sep - 07 Oct	SKY express

Also check the deals for one-way flights from Thessaloniki to Istanbul 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 Thessaloniki to Istanbul in September from $246

Return flights