AirHint found the following cheapest return flights from Washington (IAD) to London (LGW) in May 2026 (see full year).

Return flights

01 May - 05 May	Icelandair
01 May - 10 May	Icelandair
01 May - 06 May	Icelandair
12 May - 17 May	Icelandair
06 May - 11 May	Icelandair
19 May - 05 Jun	Icelandair
06 May - 15 May	Icelandair
04 May - 15 May	Icelandair
06 May - 29 May	Icelandair
08 May - 26 May	Icelandair
14 May - 25 May	Icelandair
21 May - 19 Jun	Icelandair
24 May - 07 Jun	Icelandair
31 May - 14 Jun	Icelandair
27 May - 02 Jun	Icelandair
25 May - 12 Jun	Icelandair
23 May - 06 Jun	Icelandair
31 May - 06 Jun	Lufthansa
29 May - 08 Jun	Turkish Airlines

Also check the deals for one-way flights from Washington 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 Washington to London in May from 386€

Return flights