Cheapest return flights from Philadelphia to London in September from $520

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

01 Sep - 01 Oct Air France
23 Sep - 09 Oct jetBlue
30 Sep - 07 Oct jetBlue
22 Sep - 29 Sep Finnair
01 Sep - 01 Oct Iberia direct
23 Sep - 30 Sep British Airways direct
29 Sep - 06 Oct British Airways
19 Sep - 04 Oct jetBlue
16 Sep - 23 Sep British Airways
08 Sep - 14 Sep American Airlines
08 Sep - 29 Sep Finnair
26 Sep - 03 Oct British Airways
01 Sep - 08 Sep United
11 Sep - 18 Sep United
21 Sep - 28 Sep United
21 Sep - 28 Sep British Airways direct
08 Sep - 29 Sep British Airways direct
19 Sep - 04 Oct Iberia direct
23 Sep - 09 Oct Finnair direct
30 Sep - 07 Oct Finnair direct

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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