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

Return flights

01 Dec - 14 Dec	ITA Airways
03 Dec - 10 Dec	Delta
26 Dec - 10 Jan	TAP
15 Dec - 28 Dec	Air Canada
28 Dec - 04 Jan	SWISS
01 Dec - 14 Dec	Iberia	direct
15 Dec - 04 Jan	WestJet
22 Dec - 29 Dec	SWISS
16 Dec - 29 Dec	TAP
16 Dec - 30 Dec	TAP
03 Dec - 10 Dec	Austrian Airlines	direct
21 Dec - 28 Dec	Lufthansa
26 Dec - 02 Jan	TAP
07 Dec - 08 Dec	Scandinavian Airlines
26 Dec - 10 Jan	British Airways	direct
18 Dec - 02 Jan	TAP
19 Dec - 01 Jan	TAP
19 Dec - 09 Jan	Air Canada
15 Dec - 04 Jan	British Airways	direct
28 Dec - 04 Jan	British Airways	direct

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

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 December from $623

Return flights