Cheapest one-way flights from Chicago to London in September from 279€

AirHint found the following cheapest one-way flights from Chicago (MDW) to London (LHR) in September 2025 (see full year).

One-Way flights

04 Sep Porter Airlines (Canada) Ltd
01 Sep Allegiant Air
03 Sep Porter Airlines (Canada) Ltd
20 Sep Porter Airlines (Canada) Ltd
19 Sep Porter Airlines (Canada) Ltd
12 Sep Porter Airlines (Canada) Ltd
22 Sep Porter Airlines (Canada) Ltd
02 Sep Porter Airlines (Canada) Ltd
23 Sep Frontier Airlines
25 Sep Porter Airlines (Canada) Ltd

Also check the deals for return 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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