AirHint found the following cheapest return flights from Montreal (YUL) to Porto (OPO) in October 2025 (see full year).

Return flights

16 Oct - 22 Oct	Air Transat	direct
08 Oct - 15 Oct	Air Transat
03 Oct - 10 Oct	Air Transat
15 Oct - 22 Oct	Air Transat
01 Oct - 15 Oct	Air Transat
05 Oct - 13 Oct	Air Transat
18 Oct - 26 Oct	Air Transat
03 Oct - 17 Oct	Air Transat
09 Oct - 16 Oct	Air Transat
10 Oct - 17 Oct	Air Transat
25 Oct - 01 Nov	Air Transat
27 Oct - 03 Nov	Azores Airlines
28 Oct - 04 Nov	SWISS
30 Oct - 06 Nov	SWISS
29 Oct - 05 Nov	SWISS
26 Oct - 02 Nov	Air Canada
31 Oct - 07 Nov	TAP
31 Oct - 02 Nov	TAP

Also check the deals for one-way flights from Montreal to Porto in October.

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 Montreal to Porto in October from $533

Return flights