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

Return flights

08 Apr - 15 Apr	Air Canada
03 Apr - 18 Apr	Frontier Airlines
30 Apr - 16 May	Frontier Airlines
23 Apr - 27 Apr	Air Canada
24 Apr - 27 Apr	Lufthansa
01 Apr - 18 Apr	Frontier Airlines
30 Apr - 10 May	Frontier Airlines
23 Apr - 28 Apr	Aer Lingus
03 Apr - 10 Apr	Air Canada
24 Apr - 09 May	Frontier Airlines
18 Apr - 25 Apr	Air Canada
02 Apr - 06 Apr	Lufthansa
17 Apr - 10 May	Frontier Airlines
17 Apr - 09 May	Frontier Airlines
14 Apr - 06 May	Frontier Airlines
17 Apr - 02 May	Frontier Airlines
01 Apr - 22 Apr	TAP
30 Apr - 05 May	Spirit Airlines
30 Apr - 19 May	TAP
30 Apr - 18 May	TAP

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

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.

Book a cheap hotel in London

Cheap car rent in London

Cheapest return flights from Philadelphia to London in April from $581

Return flights