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

Return flights

29 Sep - 01 Oct	Lufthansa
29 Sep - 30 Sep	Lufthansa
22 Sep - 30 Sep	Lufthansa
23 Sep - 30 Sep	Lufthansa
26 Sep - 30 Sep	Lufthansa
30 Sep - 07 Oct	Lufthansa
30 Sep - 01 Oct	Lufthansa
25 Sep - 26 Sep	Lufthansa
22 Sep - 24 Sep	Lufthansa
23 Sep - 25 Sep	Lufthansa
24 Sep - 26 Sep	Lufthansa
23 Sep - 26 Sep	Lufthansa
22 Sep - 26 Sep	Lufthansa
30 Sep - 03 Oct	Lufthansa
18 Sep - 09 Oct	Lufthansa
23 Sep - 02 Oct	Lufthansa
30 Sep - 02 Oct	Lufthansa
27 Sep - 03 Oct	ITA Airways
18 Sep - 03 Oct	Lufthansa
28 Sep - 07 Oct	SWISS

Also check the deals for one-way flights from London to Brussels in September.

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 September from $266

Return flights