Cheapest return flights from Chicago to London in September from $616

Best time to book flights for Chicago (ORD) to London (LGW) flights at AirHint

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

Return flights

15 Sep - 29 Sep Turkish Airlines
05 Sep - 19 Sep Icelandair
15 Sep - 22 Sep Turkish Airlines
18 Sep - 22 Sep Turkish Airlines
15 Sep - 02 Oct Icelandair
05 Sep - 16 Sep Icelandair
14 Sep - 22 Sep Icelandair
14 Sep - 23 Sep Icelandair
04 Sep - 20 Sep Icelandair
19 Sep - 28 Sep Turkish Airlines
01 Sep - 07 Sep Icelandair
11 Sep - 02 Oct Icelandair

Also check the deals for one-way flights from Chicago to London in September.

Skyscanner

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