AirHint found the following cheapest return flights from Philadelphia (PHL) to London (LHR) in May 2026 (see full year).

Return flights

05 May - 12 May	jetBlue
03 May - 07 May	jetBlue
12 May - 18 May	jetBlue
04 May - 08 May	jetBlue
01 May - 03 May	Air Canada
07 May - 11 May	jetBlue
01 May - 10 May	jetBlue
01 May - 08 May	jetBlue
01 May - 09 May	jetBlue
02 May - 16 May	jetBlue
17 May - 05 Jun	British Airways	direct
27 May - 06 Jun	Air Canada
17 May - 07 Jun	British Airways	direct
17 May - 08 Jun	British Airways	direct
17 May - 06 Jun	British Airways
27 May - 24 Jun	TAP
28 May - 07 Jun	jetBlue
26 May - 07 Jun	Aer Lingus
25 May - 01 Jun	Aer Lingus
25 May - 01 Jun	British Airways	direct

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

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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Cheapest return flights from Philadelphia to London in May from $681

Return flights