Cheapest return flights from Philadelphia to Lisbon in September from $918

Best time to book flights for Philadelphia (PHL) to Lisbon (LIS) flights at AirHint

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

Return flights

24 Sep - 11 Oct TAP
11 Sep - 21 Sep TAP
23 Sep - 30 Sep United
08 Sep - 05 Oct TAP
05 Sep - 10 Sep Scandinavian Airlines
24 Sep - 11 Oct Finnair direct
03 Sep - 10 Sep United
08 Sep - 05 Oct American Airlines direct
11 Sep - 21 Sep American Airlines direct
13 Sep - 20 Sep United

Also check the deals for one-way flights from Philadelphia to Lisbon 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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