AirHint found the following cheapest return flights from San Francisco (SFO) to London (LHR) in May 2026 (see full year).

Return flights

08 May - 20 May	TAP
01 May - 15 May	TAP
12 May - 19 May	TAP
05 May - 11 May	TAP
14 May - 21 May	TAP
07 May - 21 May	TAP
07 May - 22 May	TAP
04 May - 12 May	Austrian Airlines
24 May - 03 Jun	Scandinavian Airlines
04 May - 12 May	British Airways	direct
12 May - 19 May	Austrian Airlines	direct
17 May - 10 Jun	Lufthansa
27 May - 09 Jun	Air Canada
24 May - 08 Jun	Air Canada
26 May - 09 Jun	Austrian Airlines
26 May - 16 Jun	SWISS
25 May - 15 Jun	Austrian Airlines
26 May - 15 Jun	Austrian Airlines
24 May - 03 Jun	American Airlines	direct
30 May - 13 Jun	Air Canada

Also check the deals for one-way flights from San Francisco to London in May.

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 Francisco to London in May from $428

Return flights