AirHint found the following cheapest return flights from Ontario (ONT) to Madrid (MAD) in May 2026 (see full year).

Return flights

05 May - 21 May	British Airways
02 May - 15 May	Iberia
19 May - 26 May	British Airways
12 May - 12 Jun	British Airways
01 May - 08 May	Iberia
16 May - 23 May	British Airways
08 May - 17 May	British Airways
01 May - 14 May	British Airways
17 May - 28 May	British Airways
20 May - 29 May	Iberia
08 May - 15 May	Iberia
08 May - 15 Jun	British Airways
21 May - 01 Jun	Iberia
29 May - 14 Jun	British Airways
25 May - 01 Jun	Iberia

Also check the deals for one-way flights from Ontario to Madrid in May.

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 Ontario to Madrid in May from $637

Return flights