AirHint found the following cheapest return flights from London (LCY) to Boston (BOS) in May 2026 (see full year).

Return flights

06 May - 19 May	SWISS
06 May - 12 May	ITA Airways
08 May - 14 May	ITA Airways
14 May - 20 May	ITA Airways
05 May - 19 May	SWISS
14 May - 19 May	SWISS
01 May - 05 May	SWISS
07 May - 11 May	Lufthansa
02 May - 12 May	SWISS
08 May - 12 May	SWISS
28 May - 01 Jun	SWISS
30 May - 06 Jun	Delta
18 May - 01 Jun	Lufthansa
25 May - 01 Jun	Lufthansa
25 May - 05 Jun	Virgin Atlantic
29 May - 06 Jun	KLM

Also check the deals for one-way flights from London to Boston in May.

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 Boston in May from $584

Return flights