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

Return flights

29 Sep - 06 Oct	WestJet
23 Sep - 06 Oct	WestJet
23 Sep - 30 Sep	Air Canada
23 Sep - 05 Oct	WestJet
02 Sep - 16 Sep	Air Canada
08 Sep - 24 Sep	WestJet
10 Sep - 15 Sep	Air Canada
27 Sep - 05 Oct	WestJet
03 Sep - 10 Sep	Air Canada
01 Sep - 01 Oct	KLM
30 Sep - 07 Oct	Delta
24 Sep - 08 Oct	WestJet
21 Sep - 14 Oct	Air Canada
29 Sep - 14 Oct	Lufthansa
21 Sep - 10 Oct	WestJet
08 Sep - 18 Sep	WestJet
18 Sep - 29 Sep	WestJet
04 Sep - 11 Sep	American Airlines
09 Sep - 29 Sep	WestJet
20 Sep - 29 Sep	Air Canada

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

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.

Book a cheap hotel in London

Cheap car rent in London

Cheapest return flights from Calgary to London in September from 808CAD

Return flights