Cheapest return flights from Philadelphia to London in September from $630

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

07 Sep - 14 Sep jetBlue
11 Sep - 25 Sep jetBlue
02 Sep - 07 Sep jetBlue
01 Sep - 10 Sep jetBlue
23 Sep - 30 Sep United
03 Sep - 10 Sep United
01 Sep - 10 Sep British Airways direct
07 Sep - 14 Sep British Airways direct
11 Sep - 25 Sep British Airways direct
13 Sep - 20 Sep 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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