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

Return flights

26 Dec - 13 Jan	TAP
26 Dec - 15 Jan	TAP
31 Dec - 13 Jan	SWISS
29 Dec - 13 Jan	SWISS
29 Dec - 29 Jan	TAP
26 Dec - 30 Jan	TAP
30 Dec - 18 Jan	SWISS
31 Dec - 12 Jan	Brussels Airlines
30 Dec - 17 Jan	SWISS
29 Dec - 30 Jan	SWISS
17 Dec - 23 Dec	Lufthansa
23 Dec - 25 Dec	Aer Lingus
24 Dec - 28 Dec	SWISS
17 Dec - 25 Dec	SWISS
22 Dec - 23 Dec	TAP
22 Dec - 25 Dec	TAP
17 Dec - 24 Dec	SWISS
25 Dec - 28 Dec	SWISS
21 Dec - 23 Dec	Frontier Airlines
20 Dec - 26 Dec	Frontier Airlines

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.

Book a cheap hotel in London

Cheap car rent in London

Cheapest return flights from San Francisco to London in December from 539€

Return flights