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

Return flights

08 May - 14 May	SWISS
14 May - 18 May	Lufthansa
12 May - 21 May	Lufthansa
15 May - 21 May	Lufthansa
14 May - 21 May	Lufthansa
01 May - 07 May	Lufthansa
11 May - 18 May	Lufthansa
13 May - 18 May	Lufthansa
15 May - 18 May	Lufthansa
07 May - 11 May	Lufthansa
15 May - 01 Jun	Lufthansa
21 May - 02 Jun	Lufthansa
13 May - 03 Jun	Lufthansa
21 May - 01 Jun	Lufthansa
28 May - 04 Jun	Lufthansa
31 May - 06 Jun	British Airways
21 May - 30 Jun	Lufthansa
25 May - 09 Jun	Lufthansa
30 May - 13 Jun	SWISS
26 May - 12 Jun	Delta

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 $522

Return flights