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

Return flights

30 Jul - 28 Aug	SWISS
06 Jul - 28 Aug	Delta
20 Jul - 11 Aug	Air Canada
28 Jul - 12 Aug	Aer Lingus
06 Jul - 28 Aug	British Airways	direct
19 Jul - 11 Aug	SWISS
24 Jul - 28 Jul	Icelandair
28 Jul - 12 Aug	United	direct
12 Jul - 20 Jul	Icelandair
05 Jul - 11 Jul	Icelandair
14 Jul - 18 Jul	Icelandair
14 Jul - 27 Jul	Icelandair
14 Jul - 23 Jul	Icelandair
05 Jul - 14 Jul	Icelandair
17 Jul - 25 Jul	Icelandair
15 Jul - 23 Jul	Icelandair
17 Jul - 21 Jul	Icelandair
28 Jul - 04 Aug	Aer Lingus
30 Jul - 09 Aug	TAP
28 Jul - 04 Aug	British Airways	direct

Also check the deals for one-way flights from Washington to London in July.

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 July from $660

Return flights