Cheapest return flights from Philadelphia to London in September from $476

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

Return flights

30 Sep - 09 Oct Aer Lingus
14 Sep - 17 Sep Aer Lingus
14 Sep - 23 Sep Aer Lingus
10 Sep - 24 Sep American Airlines
10 Sep - 15 Sep British Airways
14 Sep - 23 Sep Finnair direct
24 Sep - 01 Oct Air Canada
10 Sep - 16 Sep British Airways direct
23 Sep - 30 Sep Air Canada
10 Sep - 24 Sep British Airways direct
21 Sep - 30 Sep Air Canada
10 Sep - 17 Sep American Airlines direct
23 Sep - 01 Oct Air Canada
30 Sep - 09 Oct British Airways direct
24 Sep - 01 Oct American Airlines direct
20 Sep - 07 Oct Aer Lingus
25 Sep - 02 Oct British Airways direct
29 Sep - 06 Oct British Airways direct
10 Sep - 04 Oct Iberia direct
12 Sep - 08 Oct British Airways

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