Cheapest return flights from San Francisco to London in September from $521

Best time to book flights for San Francisco (SFO) to London (LHR) flights at AirHint

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

Return flights

30 Sep - 09 Oct TAP
22 Sep - 29 Sep TAP
16 Sep - 24 Sep TAP
25 Sep - 02 Oct TAP
02 Sep - 09 Sep TAP
09 Sep - 09 Oct TAP
25 Sep - 23 Oct TAP
23 Sep - 30 Sep Scandinavian Airlines
10 Sep - 24 Sep Aer Lingus
10 Sep - 01 Oct Scandinavian Airlines
11 Sep - 15 Sep Scandinavian Airlines
07 Sep - 16 Sep Aer Lingus
03 Sep - 30 Sep Aer Lingus
22 Sep - 03 Oct Aer Lingus
16 Sep - 28 Sep Scandinavian Airlines
10 Sep - 15 Sep Air Canada
10 Sep - 01 Oct Finnair direct
09 Sep - 09 Oct Finnair direct
22 Sep - 03 Oct Delta direct
30 Sep - 09 Oct British Airways direct

Also check the deals for one-way flights from San Francisco 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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