Cheapest return flights from London to Boston in September from $435

Best time to book flights for London (LHR) to Boston (BOS) flights at AirHint

AirHint found the following cheapest return flights from London (LHR) to Boston (BOS) in September 2025 (see full year).

Return flights

16 Sep - 23 Sep SWISS
24 Sep - 28 Sep SWISS
24 Sep - 30 Sep SWISS
24 Sep - 01 Oct SWISS
15 Sep - 24 Sep Austrian Airlines
08 Sep - 16 Sep Austrian Airlines
08 Sep - 22 Sep Austrian Airlines
09 Sep - 16 Sep Austrian Airlines
10 Sep - 17 Sep Austrian Airlines
16 Sep - 21 Sep SWISS
03 Sep - 24 Sep Virgin Atlantic
24 Sep - 01 Oct British Airways direct
29 Sep - 06 Oct Lufthansa
22 Sep - 15 Oct Lufthansa
30 Sep - 07 Oct Lufthansa
22 Sep - 15 Oct British Airways direct
29 Sep - 06 Oct British Airways direct
30 Sep - 07 Oct British Airways direct
30 Sep - 14 Oct Lufthansa
29 Sep - 08 Oct Delta direct

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

Skyscanner

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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