Cheapest return flights from Ontario (ONT) to London (LHR), May

13 dates in May 2027, from $ 807. Book in one tap, or check whether to buy now or wait.

One-wayReturn
Dates, airline, and price
Dates Airline Price
12 May 22 May 2027 Alaska Airlines
4 May 21 May 2027 British Airways
5 May 26 May 2027 British Airways
12 May 5 Jun 2027 Alaska Airlines
18 May 29 Jun 2027 British Airways
19 May 7 Jun 2027 Alaska Airlines
16 May 5 Jun 2027 Alaska Airlines
15 May 5 Jun 2027 Alaska Airlines
23 May 8 Jun 2027 jetBlue
10 May 16 May 2027 Alaska Airlines
24 May 31 May 2027 Alaska Airlines
22 May 31 May 2027 British Airways
21 May 22 May 2027 Alaska Airlines
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Deals for one-way flights from Ontario to London in May.

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About these fares

These results come from our latest search across airlines for your currency. Prices change quickly and are not locked until you complete booking—always confirm the total and fare rules on the partner site.

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