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

Return flights

12 Sep - 14 Sep	Finnair
26 Sep - 28 Sep	Finnair
08 Sep - 10 Oct	TAP
07 Sep - 21 Sep	TAP
08 Sep - 20 Sep	TAP
11 Sep - 25 Sep	TAP
23 Sep - 04 Oct	TAP
02 Sep - 26 Sep	TAP
30 Sep - 16 Oct	TAP
02 Sep - 14 Oct	TAP
25 Sep - 22 Oct	TAP
22 Sep - 06 Oct	TAP
14 Sep - 01 Oct	TAP
26 Sep - 08 Oct	TAP
24 Sep - 05 Oct	TAP
02 Sep - 11 Sep	TAP
15 Sep - 25 Sep	TAP
28 Sep - 07 Oct	TAP
04 Sep - 11 Sep	TAP
03 Sep - 10 Sep	TAP

Also check the deals for one-way flights from New York to London 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 New York to London in September from 292€

Return flights