AirHint found the following cheapest return flights from Ontario (ONT) to London (LHR) in July 2025 (see full year).

Return flights

31 Jul - 05 Aug	United
27 Jul - 07 Aug	Iberia
27 Jul - 13 Aug	Iberia
23 Jul - 30 Jul	Delta
30 Jul - 07 Aug	Iberia
27 Jul - 14 Aug	British Airways
30 Jul - 10 Aug	British Airways
25 Jul - 30 Jul	British Airways
22 Jul - 04 Aug	British Airways
30 Jul - 04 Aug	British Airways
21 Jul - 04 Aug	British Airways
19 Jul - 09 Aug	British Airways
15 Jul - 30 Jul	British Airways
06 Jul - 17 Jul	Iberia
16 Jul - 31 Jul	British Airways
03 Jul - 08 Jul	jetBlue
05 Jul - 19 Jul	jetBlue
08 Jul - 19 Jul	jetBlue
22 Jul - 27 Jul	British Airways
21 Jul - 31 Jul	jetBlue

Also check the deals for one-way flights from Ontario to London in July.

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 London in July from $751

Return flights