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

Return flights

03 Sep - 19 Sep	KLM
03 Sep - 30 Sep	KLM
24 Sep - 04 Oct	Delta
05 Sep - 13 Sep	Delta
03 Sep - 10 Sep	Delta
02 Sep - 10 Sep	Delta
04 Sep - 22 Oct	Delta
02 Sep - 23 Sep	Lufthansa
02 Sep - 29 Sep	Lufthansa
03 Sep - 18 Sep	KLM
06 Sep - 13 Sep	Delta
18 Sep - 27 Sep	Delta
10 Sep - 08 Oct	Lufthansa
10 Sep - 21 Oct	Lufthansa
18 Sep - 11 Oct	Delta
19 Sep - 08 Oct	SWISS
23 Sep - 07 Oct	KLM
22 Sep - 06 Oct	KLM
28 Sep - 05 Oct	KLM
25 Sep - 07 Oct	KLM

Also check the deals for one-way flights from London to Buenos Aires 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.

Book a cheap hotel in Buenos Aires

Cheap car rent in Buenos Aires

Cheapest return flights from London to Buenos Aires in September from $1140

Return flights