Cheapest return flights from Philadelphia to Lisbon in September from $613

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

18 Sep - 25 Sep American Airlines
18 Sep - 21 Sep British Airways
04 Sep - 11 Sep Aer Lingus
11 Sep - 17 Sep Aer Lingus
03 Sep - 10 Sep Spirit Airlines
09 Sep - 16 Sep Finnair
03 Sep - 10 Sep Iberia direct
26 Sep - 03 Oct United
18 Sep - 25 Sep Iberia direct
09 Sep - 16 Sep British Airways direct
18 Sep - 21 Sep British Airways direct

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

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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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