Cheapest return flights from Philadelphia to Lisbon in September from $775

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

Return flights

24 Sep - 01 Oct Air Canada
24 Sep - 30 Sep Spirit Airlines
25 Sep - 30 Sep Frontier Airlines
30 Sep - 25 Oct Spirit Airlines
23 Sep - 05 Oct TAP
24 Sep - 18 Oct Frontier Airlines
24 Sep - 01 Oct Iberia direct
22 Sep - 01 Oct American Airlines direct
24 Sep - 18 Oct Finnair direct
25 Sep - 30 Sep British Airways direct
23 Sep - 05 Oct American Airlines direct

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.

Book a cheap hotel in Lisbon

Cheap car rent in Lisbon

Feel free to contact us with any feedback or request another flight research.