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

Return flights

02 Dec - 09 Dec	Air Canada
10 Dec - 16 Dec	Air Canada
04 Dec - 14 Dec	Air Canada
24 Dec - 08 Jan	Air Canada
27 Dec - 10 Jan	Air Canada
16 Dec - 23 Dec	Air Canada
12 Dec - 19 Dec	United
21 Dec - 29 Dec	Air Canada
21 Dec - 28 Dec	Air Canada
24 Dec - 01 Jan	Scandinavian Airlines
22 Dec - 05 Jan	Sun Country Airlines
22 Dec - 29 Dec	United
19 Dec - 28 Dec	Air Canada
27 Dec - 10 Jan	Alaska Airlines	direct
24 Dec - 08 Jan	British Airways	direct
21 Dec - 29 Dec	Finnair	direct

Also check the deals for one-way flights from San Diego 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 Diego to London in December from $519

Return flights