AirHint found the following cheapest return flights from London (LCY) to Brussels (BRU) in December 2025 (see full year).

Return flights

11 Dec - 16 Dec	ITA Airways
11 Dec - 15 Dec	ITA Airways
18 Dec - 23 Dec	KLM
31 Dec - 06 Jan	KLM
10 Dec - 15 Dec	Lufthansa
03 Dec - 04 Dec	Lufthansa
02 Dec - 09 Dec	Lufthansa
02 Dec - 05 Dec	Lufthansa
03 Dec - 08 Dec	Lufthansa
02 Dec - 03 Dec	Lufthansa
03 Dec - 09 Dec	Lufthansa
26 Dec - 07 Jan	Lufthansa
24 Dec - 05 Jan	KLM
17 Dec - 13 Jan	KLM
29 Dec - 05 Jan	KLM
26 Dec - 01 Jan	KLM
27 Dec - 11 Jan	KLM
12 Dec - 11 Jan	KLM
24 Dec - 01 Jan	KLM
31 Dec - 01 Jan	Lufthansa

Also check the deals for one-way flights from London to Brussels 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 London to Brussels in December from $265

Return flights