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

Return flights

06 Dec - 12 Dec	TAP
04 Dec - 11 Dec	TAP
04 Dec - 14 Dec	TAP
04 Dec - 09 Dec	TAP
05 Dec - 07 Dec	Scandinavian Airlines
30 Dec - 13 Jan	Lufthansa
11 Dec - 15 Dec	Lufthansa
02 Dec - 10 Dec	Aer Lingus
30 Dec - 13 Jan	jetBlue	direct
16 Dec - 08 Jan	Icelandair
12 Dec - 19 Dec	Lufthansa
16 Dec - 23 Dec	Icelandair
29 Dec - 07 Jan	Lufthansa
08 Dec - 15 Dec	United
30 Dec - 15 Jan	United
15 Dec - 10 Jan	Aer Lingus
29 Dec - 24 Jan	Aer Lingus
13 Dec - 12 Jan	Aer Lingus
29 Dec - 07 Jan	jetBlue	direct
30 Dec - 15 Jan	British Airways	direct

Also check the deals for one-way flights from Boston 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 Boston to London in December from 365€

Return flights