Cheapest return flights from Philadelphia to London in August 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 August 2025 (see full year).

Return flights

05 Aug - 21 Aug Delta
13 Aug - 19 Aug American Airlines
04 Aug - 18 Aug Finnair
21 Aug - 25 Aug Delta
27 Aug - 03 Sep United
12 Aug - 19 Aug British Airways
09 Aug - 22 Aug British Airways
30 Aug - 06 Sep Virgin Atlantic
08 Aug - 20 Aug American Airlines
17 Aug - 24 Aug United
22 Aug - 29 Aug United
05 Aug - 21 Aug British Airways direct
30 Aug - 06 Sep British Airways direct

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

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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