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

Return flights

27 Sep - 07 Oct	Air Canada
27 Sep - 08 Oct	Air Canada
03 Sep - 08 Sep	Air Canada
01 Sep - 11 Sep	Air Canada
03 Sep - 12 Sep	Air Canada
09 Sep - 23 Sep	Air Canada
10 Sep - 22 Sep	Air Canada
24 Sep - 06 Oct	Air Canada
23 Sep - 29 Sep	Air Canada
07 Sep - 15 Sep	Lufthansa
03 Sep - 07 Sep	Air Canada
02 Sep - 07 Sep	Air Canada
30 Sep - 05 Oct	Lufthansa
29 Sep - 05 Oct	Air Canada
22 Sep - 28 Sep	Air Canada
28 Sep - 04 Oct	Air Canada
30 Sep - 07 Oct	United
25 Sep - 09 Oct	Air Canada
24 Sep - 01 Oct	United
24 Sep - 01 Oct	British Airways	direct

Also check the deals for one-way flights from San Diego 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.

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Cheapest return flights from San Diego to London in September from $520

Return flights