How does KAYAK find such low prices on flights from Illinois to London?

KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from Illinois to London.

How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Illinois to London?

KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to London from Illinois is likely to change within 7 days, so travelers know whether to wait or book now.

What is the Hacker Fare option on flights from Illinois to London?

Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly to London with an airline and back to Illinois with another airline.

What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Illinois to London?

Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying to London from Illinois up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

$320 CHEAP FLIGHTS from Illinois to London

Save 26% or more on flights. Compare deals from all over the web.

Never overpay with our price tracking tools.

Filter searches by price, airline and more to find your best flights.

Flight Deals

Cheap Flights from Illinois to London

Discover the best prices for you by selecting your travel dates on KAYAK.

Round-trip

One-way

Last minute

Direct

Recent round-trip flight deals from Illinois to London

Sun, Feb 7 - Wed, Feb 10

7:10 pm - 8:10 pmORD Chicago O'Hare Intl-LGW London Gatwick

19h 00m2 stops Kastrup Copenhagen Oslo Gardermoen

5:40 pm - 4:45 pmLGW London Gatwick-ORD Chicago O'Hare Intl

29h 05m2 stops Oslo Gardermoen Kastrup Copenhagen

$650Multiple Airlines

Sun, Feb 7 - Mon, Feb 15

6:30 pm - 10:35 amORD Chicago O'Hare Intl-LGW London Gatwick

34h 05m3 stops Reykjavik Keflavik Intl Stockholm Arlanda Kastrup Copenhagen

2:05 pm - 5:20 pmLGW London Gatwick-ORD Chicago O'Hare Intl

33h 15m3 stops Kastrup Copenhagen Stockholm Arlanda Reykjavik Keflavik Intl

$650Multiple Airlines

Wed, Mar 31 - Sun, Apr 18

7:25 pm - 2:40 pmORD Chicago O'Hare Intl-LGW London Gatwick

13h 15m1 stop Reykjavik Keflavik Intl

3:40 pm - 9:25 pmLGW London Gatwick-ORD Chicago O'Hare Intl

11h 45m1 stop Reykjavik Keflavik Intl

$651Icelandair

Thu, Mar 11 - Sun, Mar 14

7:10 pm - 9:35 amORD Chicago O'Hare Intl-LHR London Heathrow

56h 25m2 stops Kastrup Copenhagen Oslo Gardermoen

9:05 pm - 5:45 pmLHR London Heathrow-ORD Chicago O'Hare Intl

25h 40m2 stops Stockholm Arlanda Kastrup Copenhagen

$652Scandinavian Airlines

Sat, Jan 9 - Mon, Jan 11

7:10 pm - 6:30 pmORD Chicago O'Hare Intl-LHR London Heathrow

17h 20m1 stop Kastrup Copenhagen

6:40 am - 4:45 pmLHR London Heathrow-ORD Chicago O'Hare Intl

16h 05m2 stops Stockholm Arlanda Kastrup Copenhagen

$655Scandinavian Airlines

Sun, Mar 28 - Wed, Apr 21

7:25 pm - 2:40 pmORD Chicago O'Hare Intl-LGW London Gatwick

13h 15m1 stop Reykjavik Keflavik Intl

3:40 pm - 9:25 pmLGW London Gatwick-ORD Chicago O'Hare Intl

11h 45m1 stop Reykjavik Keflavik Intl

$663Icelandair

Sun, Mar 28 - Sun, Apr 18

5:45 pm - 12:45 pmORD Chicago O'Hare Intl-LHR London Heathrow

13h 00m1 stop Lisbon Humberto Delgado

6:00 am - 4:00 pmLHR London Heathrow-ORD Chicago O'Hare Intl

16h 00m1 stop Lisbon Humberto Delgado

$682TAP AIR PORTUGAL

Wed, Mar 31 - Sun, Apr 18

5:45 pm - 12:45 pmORD Chicago O'Hare Intl-LHR London Heathrow

13h 00m1 stop Lisbon Humberto Delgado

6:00 am - 4:00 pmLHR London Heathrow-ORD Chicago O'Hare Intl

16h 00m1 stop Lisbon Humberto Delgado

$691TAP AIR PORTUGAL

Mon, Mar 29 - Tue, Apr 20

10:00 pm - 12:00 pmORD Chicago O'Hare Intl-LHR London Heathrow

8h 00mnonstop

4:05 pm - 6:59 pmLHR London Heathrow-ORD Chicago O'Hare Intl

8h 54mnonstop

$731British Airways

Tue, Mar 30 - Tue, Apr 20

5:00 pm - 6:50 amORD Chicago O'Hare Intl-LHR London Heathrow

7h 50mnonstop

11:10 am - 1:50 pmLHR London Heathrow-ORD Chicago O'Hare Intl

8h 40mnonstop

$740British Airways

Recent last minute flight deals from Illinois to London

Fri, Nov 13 - Sat, Nov 21

8:10 pm - 9:50 pmORD Chicago O'Hare Intl-STN London Stansted

19h 40m2 stops Lisbon Humberto Delgado Madrid Barajas

3:40 pm - 3:30 pmSTN London Stansted-ORD Chicago O'Hare Intl

29h 50m2 stops Madrid Barajas Lisbon Humberto Delgado

$706Multiple Airlines

Fri, Nov 13 - Sat, Nov 21

8:10 pm - 8:50 pmORD Chicago O'Hare Intl-LTN London Luton

18h 40m2 stops Lisbon Humberto Delgado Madrid Barajas

9:30 pm - 3:30 pmLTN London Luton-ORD Chicago O'Hare Intl

24h 00m2 stops Madrid Barajas Lisbon Humberto Delgado

$716Multiple Airlines

Sun, Nov 15 - Wed, Nov 18

7:10 pm - 9:35 pmORD Chicago O'Hare Intl-LHR London Heathrow

44h 25m2 stops Kastrup Copenhagen Oslo Gardermoen

1:55 pm - 4:45 pmLHR London Heathrow-ORD Chicago O'Hare Intl

32h 50m2 stops Stockholm Arlanda Kastrup Copenhagen

$726Scandinavian Airlines

Mon, Nov 16 - Tue, Nov 24

6:30 pm - 10:50 amORD Chicago O'Hare Intl-LHR London Heathrow

10h 20m1 stop Reykjavik Keflavik Intl

8:35 pm - 5:20 pmLHR London Heathrow-ORD Chicago O'Hare Intl

26h 45m1 stop Reykjavik Keflavik Intl

$738Icelandair

Mon, Nov 16 - Mon, Nov 23

6:30 pm - 7:30 pmORD Chicago O'Hare Intl-LHR London Heathrow

19h 00m1 stop Reykjavik Keflavik Intl

8:35 pm - 5:20 pmLHR London Heathrow-ORD Chicago O'Hare Intl

26h 45m1 stop Reykjavik Keflavik Intl

$738Icelandair

Fri, Nov 13 - Sun, Nov 22

5:10 pm - 6:55 amORD Chicago O'Hare Intl-LHR London Heathrow

7h 45mnonstop

11:00 am - 1:45 pmLHR London Heathrow-ORD Chicago O'Hare Intl

8h 45mnonstop

$761British Airways

Sat, Nov 14 - Wed, Nov 25

7:10 pm - 4:00 pmORD Chicago O'Hare Intl-LHR London Heathrow

14h 50m1 stop Kastrup Copenhagen

6:40 pm - 4:45 pmLHR London Heathrow-ORD Chicago O'Hare Intl

28h 05m1 stop Kastrup Copenhagen

$766Scandinavian Airlines

Fri, Nov 13 - Thu, Nov 19

8:10 pm - 3:45 pmORD Chicago O'Hare Intl-LGW London Gatwick

13h 35m1 stop Lisbon Humberto Delgado

4:00 pm - 3:30 pmLGW London Gatwick-ORD Chicago O'Hare Intl

29h 30m1 stop Lisbon Humberto Delgado

$796TAP AIR PORTUGAL

Fri, Nov 13 - Fri, Nov 20

8:10 pm - 10:40 pmORD Chicago O'Hare Intl-LHR London Heathrow

20h 30m1 stop Lisbon Humberto Delgado

6:00 am - 3:30 pmLHR London Heathrow-ORD Chicago O'Hare Intl

15h 30m1 stop Lisbon Humberto Delgado

$797TAP AIR PORTUGAL

Wed, Nov 11 - Wed, Nov 18

5:10 pm - 6:55 amORD Chicago O'Hare Intl-LHR London Heathrow

7h 45mnonstop

11:00 am - 1:45 pmLHR London Heathrow-ORD Chicago O'Hare Intl

8h 45mnonstop

$966British Airways

Recent direct flight deals from Illinois to London

Mon, Mar 29 - Tue, Apr 20

10:00 pm - 12:00 pmORD Chicago O'Hare Intl-LHR London Heathrow

8h 00mnonstop

4:05 pm - 6:59 pmLHR London Heathrow-ORD Chicago O'Hare Intl

8h 54mnonstop

$731British Airways

Tue, Mar 30 - Tue, Apr 20

5:00 pm - 6:50 amORD Chicago O'Hare Intl-LHR London Heathrow

7h 50mnonstop

11:10 am - 1:50 pmLHR London Heathrow-ORD Chicago O'Hare Intl

8h 40mnonstop

$740British Airways

Wed, Mar 17 - Tue, Mar 23

9:40 pm - 10:25 amORD Chicago O'Hare Intl-LHR London Heathrow

7h 45mnonstop

11:15 am - 3:10 pmLHR London Heathrow-ORD Chicago O'Hare Intl

8h 55mnonstop

$882Iberia

Wed, Feb 10 - Wed, Feb 17

6:45 pm - 8:35 amORD Chicago O'Hare Intl-LHR London Heathrow

7h 50mnonstop

4:30 pm - 7:15 pmLHR London Heathrow-ORD Chicago O'Hare Intl

8h 45mnonstop

$882Iberia

Wed, Mar 10 - Tue, Mar 16

8:40 pm - 10:25 amORD Chicago O'Hare Intl-LHR London Heathrow

7h 45mnonstop

11:00 am - 2:45 pmLHR London Heathrow-ORD Chicago O'Hare Intl

8h 45mnonstop

$883Finnair

Sun, Dec 6 - Tue, Dec 15

6:35 pm - 8:35 amORD Chicago O'Hare Intl-LHR London Heathrow

8h 00mnonstop

4:30 pm - 7:25 pmLHR London Heathrow-ORD Chicago O'Hare Intl

8h 55mnonstop

$896Finnair

Sun, Feb 7 - Fri, Feb 19

5:10 pm - 6:55 amORD Chicago O'Hare Intl-LHR London Heathrow

7h 45mnonstop

11:00 am - 1:45 pmLHR London Heathrow-ORD Chicago O'Hare Intl

8h 45mnonstop

$900Aer Lingus

Sun, Mar 28 - Wed, Mar 31

5:00 pm - 6:50 amORD Chicago O'Hare Intl-LHR London Heathrow

7h 50mnonstop

11:10 am - 1:50 pmLHR London Heathrow-ORD Chicago O'Hare Intl

8h 40mnonstop

$901Aer Lingus

Tue, Mar 2 - Tue, Mar 16

6:50 pm - 8:35 amORD Chicago O'Hare Intl-LHR London Heathrow

7h 45mnonstop

11:15 am - 3:10 pmLHR London Heathrow-ORD Chicago O'Hare Intl

8h 55mnonstop

$901Multiple Airlines

Wed, Feb 10 - Tue, Feb 16

3:45 pm - 5:55 amORD Chicago O'Hare Intl-LHR London Heathrow

8h 10mnonstop

7:40 am - 10:45 amLHR London Heathrow-ORD Chicago O'Hare Intl

9h 05mnonstop

$909Brussels Airlines

Useful Info

Low season	February
High season	March
Cheapest flight	$320

Best time to beat the crowds with an average 23% drop in price.

Most popular time to fly and prices are also 17% lower on average.

Flight from Chicago O'Hare Airport to London Gatwick Airport

JKFlew with American Airlines-Sep 2026

Ask ahead of time, if the aircraft can provide AC and/or oxygen to passengers after boarding.

Verified travelerFlew with British Airways-Mar 2026

Take early morning flights to adjust to weather-related delays.

Verified travelerFlew with British Airways-Jun 2025

Get a wheel chair if you have difficulty walking

JoeFlew with Iberia-Apr 2025

Get there early. Nice airport options while you wait.

Verified travelerFlew with Iberia-May 2025

Get to the airport early so you’re relaxed. Con yourself into believing it’s bedtime and try to sleep so that you can keep going all day when you get there. If you can afford more comfy seats it might be worth it - though I always have the cheap ones so I can’t say for sure. Try very hard not to. sit in the middle. I’m small and the guy next to me played games all night and didn’t care that he continually ( with every move) jabbed me with his arm. This was my first flight with Cheap Flights and it was far less convenient than other times I’ve flown overseas.

DinaFlew with United Airlines-Jan 2025

Anticipate delays, prepare for long walks through Heathrow to baggage claim or for connections.

KariFlew with British Airways-May 2024

Always check to confirm your assistance is in system. No wheelchair waiting for me in London. Had no clue about airport or how to get around. Got lost easy

AaronFlew with American Airlines-Dec 2023

Find a flight where you are allowed to choose your seats before the day of boarding for anything international.

How does KAYAK find such low prices on flights from Illinois to London?
KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from Illinois to London.
How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Illinois to London?
KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to London from Illinois is likely to change within 7 days, so travelers know whether to wait or book now.
What is the Hacker Fare option on flights from Illinois to London?
Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly to London with an airline and back to Illinois with another airline.
What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Illinois to London?
Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying to London from Illinois up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

Hounslow

Hayes

Slough

Richmond

Wembley

Luton

Ilford

Eastbourne

Kingston upon Thames

Guildford

Crawley

Bedford

Watford

Harrow

Ipswich

Folkestone

St. Albans

Colchester

Woodbridge

Maidstone

More options for your flight to London

Add a hotel or car rental

Cabin class

Direct Flights

Origins

Other airports

Other destinations

Return flight

Complete your trip to London with a hotel stay or car rental

Car rentals in London

$320 Find Cheap Flights from Illinois to London - Compare and Save

Cheap Flights from Illinois to London

Recent round-trip flight deals from Illinois to London

Recent one-way flight deals from Illinois to London

Recent last minute flight deals from Illinois to London

Recent direct flight deals from Illinois to London

Good to know

Low season

High season

Cheapest flight

Flights from Illinois to London: the best tips from KAYAK users

FAQs for booking flights from Illinois to London

Traveling to a place near London?

More options for your flight to London

Complete your trip to London with a hotel stay or car rental

Cabin class types available on flights to Illinois

Find direct flights for London

Flights from domestic origins to London

Choose which airport to fly into in London

Flights to other popular destinations

Find deals for your return flight