AirHint found the following cheapest return flights from Monterrey (MTY) to Buenos Aires (AEP) in September 2025 (see full year).

Return flights

08 Sep - 17 Oct	Viva
22 Sep - 30 Sep	Viva
23 Sep - 30 Sep	Viva
19 Sep - 26 Sep	Viva
05 Sep - 16 Sep	Viva
26 Sep - 04 Oct	Viva
10 Sep - 24 Sep	Viva
09 Sep - 23 Sep	Viva
08 Sep - 22 Sep	Viva
08 Sep - 15 Sep	Viva
24 Sep - 30 Sep	Viva
12 Sep - 22 Sep	Volaris
11 Sep - 07 Oct	Viva
30 Sep - 14 Oct	LATAM Airlines Group
22 Sep - 02 Oct	LATAM Airlines Group
30 Sep - 16 Oct	LATAM Airlines Group
29 Sep - 13 Oct	LATAM Airlines Group
30 Sep - 10 Oct	LATAM Airlines Group
10 Sep - 07 Oct	Volaris

Also check the deals for one-way flights from Monterrey to Buenos Aires 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 Monterrey to Buenos Aires in September from $794

Return flights