Cheapest return flights from Chicago to London in September from $603

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

26 Sep - 30 Sep TAP
29 Sep - 06 Oct Icelandair
22 Sep - 29 Sep TAP
23 Sep - 30 Sep Icelandair
02 Sep - 12 Sep Icelandair
02 Sep - 07 Sep Icelandair
02 Sep - 20 Sep Icelandair
09 Sep - 16 Sep jetBlue
03 Sep - 07 Sep jetBlue
26 Sep - 03 Oct Icelandair
20 Sep - 28 Sep Turkish Airlines
10 Sep - 14 Sep jetBlue

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.

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