AirHint found the following cheapest return flights from Chicago (ORD) to London (LHR) in May 2026 (see full year).

Return flights

03 May - 13 May	TAP
02 May - 09 May	TAP
09 May - 16 May	TAP
06 May - 12 May	TAP
02 May - 16 May	TAP
04 May - 20 May	Icelandair
12 May - 19 May	Icelandair
04 May - 09 May	Icelandair
13 May - 19 May	Icelandair
01 May - 10 May	Icelandair
10 May - 10 Jun	Icelandair
20 May - 07 Jun	Icelandair
19 May - 07 Jun	Icelandair
23 May - 01 Jun	Aer Lingus
28 May - 01 Jun	Aer Lingus
26 May - 02 Jun	Icelandair
29 May - 06 Jun	Finnair	direct
23 May - 01 Jun	Finnair	direct

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

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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Cheapest return flights from Chicago to London in May from $439

Return flights