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

Return flights

04 Mar - 11 Mar	Aer Lingus
03 Mar - 10 Mar	Frontier Airlines
01 Mar - 10 Mar	Frontier Airlines
04 Mar - 09 Mar	Frontier Airlines
25 Mar - 31 Mar	Frontier Airlines
04 Mar - 14 Mar	Lufthansa
07 Mar - 15 Mar	Frontier Airlines
18 Mar - 22 Mar	Air Canada
22 Mar - 30 Mar	Lufthansa
24 Mar - 30 Mar	Frontier Airlines
31 Mar - 08 Apr	Aer Lingus
23 Mar - 01 Apr	Frontier Airlines
29 Mar - 17 Apr	Aer Lingus
28 Mar - 05 Apr	Aer Lingus
28 Mar - 04 Apr	Lufthansa

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

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 March from 536€

Return flights