AirHint found the following cheapest return flights from New York (LGA) to Lisbon (LIS) in September 2025 (see full year).

Return flights

22 Sep - 29 Sep	Air Canada
03 Sep - 10 Sep	Air Canada
04 Sep - 11 Sep	Air Canada
02 Sep - 09 Sep	Air Canada
14 Sep - 21 Sep	Air Canada
01 Sep - 08 Sep	Air Canada
10 Sep - 17 Sep	Air Canada
30 Sep - 10 Oct	Delta
24 Sep - 02 Oct	Delta
30 Sep - 16 Oct	Delta
08 Sep - 15 Sep	Air France
24 Sep - 30 Sep	KLM
22 Sep - 30 Sep	Air France
27 Sep - 04 Oct	Air Canada
23 Sep - 01 Oct	KLM
23 Sep - 09 Oct	Lufthansa
27 Sep - 05 Oct	Delta
29 Sep - 02 Oct	Air Transat
06 Sep - 05 Oct	Delta
15 Sep - 16 Oct	Lufthansa

Also check the deals for one-way flights from New York to Lisbon 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 Lisbon in September from 334€

Return flights