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

Return flights

11 Aug - 31 Aug	TAP
16 Aug - 25 Aug	TAP
12 Aug - 07 Sep	TAP
22 Aug - 01 Sep	TAP
22 Aug - 29 Aug	TAP
26 Aug - 17 Sep	TAP
29 Aug - 05 Sep	TAP
20 Aug - 03 Sep	TAP
07 Aug - 28 Aug	TAP
26 Aug - 01 Sep	Icelandair
11 Aug - 18 Aug	TAP
04 Aug - 11 Aug	TAP
13 Aug - 17 Aug	SWISS
03 Aug - 10 Aug	TAP
06 Aug - 16 Aug	TAP

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

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 Washington to London in August from $604

Return flights