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

Return flights

27 Oct - 05 Nov	Finnair
27 Oct - 05 Nov	Iberia	direct
26 Oct - 04 Nov	British Airways
19 Oct - 08 Nov	British Airways	direct
14 Oct - 22 Oct	Frontier Airlines
30 Oct - 06 Nov	Iberia
15 Oct - 08 Nov	British Airways
05 Oct - 09 Oct	Spirit Airlines
08 Oct - 13 Oct	Lufthansa
17 Oct - 22 Oct	Air Canada
07 Oct - 14 Oct	Aer Lingus
14 Oct - 16 Oct	Frontier Airlines
15 Oct - 21 Oct	Delta
07 Oct - 01 Nov	Finnair
11 Oct - 01 Nov	TAP
01 Oct - 09 Oct	Spirit Airlines
09 Oct - 16 Oct	Frontier Airlines
23 Oct - 27 Oct	Frontier Airlines
08 Oct - 01 Nov	Spirit Airlines
15 Oct - 08 Nov	Iberia	direct

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

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

Cheapest return flights from Philadelphia to Lisbon in October from 450€

Return flights