Cheapest return flights from Philadelphia to London in December from $653

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 December 2025 (see full year).

Return flights

05 Dec - 12 Dec British Airways
15 Dec - 22 Dec United
13 Dec - 03 Jan Air Canada
24 Dec - 01 Jan Air Canada
25 Dec - 29 Dec Delta
25 Dec - 29 Dec Finnair direct
24 Dec - 01 Jan Iberia direct
22 Dec - 02 Jan Iberia direct
25 Dec - 01 Jan United
13 Dec - 03 Jan Iberia direct
15 Dec - 22 Dec British Airways direct
25 Dec - 01 Jan British Airways direct

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

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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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