Cheapest return flights from Ottawa to London in September from $663

Best time to book flights for Ottawa (YOW) to London (LHR) flights at AirHint

AirHint found the following cheapest return flights from Ottawa (YOW) to London (LHR) in September 2025 (see full year).

Return flights

10 Sep - 27 Sep Porter Airlines (Canada) Ltd
14 Sep - 29 Sep Air Canada
03 Sep - 10 Sep Air Canada
10 Sep - 26 Sep Air Canada
11 Sep - 22 Sep Air Canada direct
05 Sep - 23 Sep Air Canada
09 Sep - 28 Sep Air Canada
04 Sep - 22 Sep Lufthansa direct
04 Sep - 23 Sep Air Canada
24 Sep - 30 Sep Air Canada
25 Sep - 01 Oct Air Canada

Also check the deals for one-way flights from Ottawa to London in September.

Skyscanner

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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