Cheapest return flights from Philadelphia to London in September from $596

Best time to book flights for Philadelphia (PHL) to London (LHR) flights at AirHint

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

Return flights

25 Sep - 09 Oct jetBlue
23 Sep - 30 Sep jetBlue
11 Sep - 14 Sep jetBlue
10 Sep - 18 Sep Iberia
02 Sep - 09 Sep Aer Lingus
01 Sep - 08 Sep Iberia
10 Sep - 18 Sep Finnair direct
23 Sep - 30 Sep British Airways direct
17 Sep - 24 Sep Delta
01 Sep - 08 Sep Iberia direct
25 Sep - 09 Oct British Airways direct
11 Sep - 14 Sep British Airways direct
27 Sep - 04 Oct United

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