AirHint found the following cheapest return flights from Chicago (ORD) to London (LGW) in August 2025 (see full year).

Return flights

20 Aug - 29 Aug	Spirit Airlines
19 Aug - 27 Aug	Spirit Airlines
15 Aug - 14 Sep	Icelandair
16 Aug - 27 Aug	Icelandair
23 Aug - 31 Aug	Icelandair
12 Aug - 21 Aug	Delta
19 Aug - 04 Sep	Delta
12 Aug - 05 Sep	Delta
12 Aug - 18 Aug	Icelandair
10 Aug - 18 Aug	Icelandair
15 Aug - 23 Aug	Icelandair
20 Aug - 25 Aug	Spirit Airlines
16 Aug - 18 Aug	Icelandair
12 Aug - 12 Sep	Spirit Airlines
20 Aug - 10 Sep	Spirit Airlines
11 Aug - 12 Sep	Icelandair
14 Aug - 09 Sep	Spirit Airlines
12 Aug - 07 Sep	Spirit Airlines
24 Aug - 01 Sep	Icelandair
13 Aug - 12 Sep	Spirit Airlines

Also check the deals for one-way flights from Chicago 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 Chicago to London in August from 413€

Return flights