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.

$316 CHEAP FLIGHTS from Illinois to London

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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

Mon, Feb 15 - Mon, Feb 22

6:30 pm - 2:05 pmORD Chicago O'Hare Intl-LTN London Luton

13h 35m1 stop Reykjavik Keflavik Intl

8:00 am - 5:20 pmLTN London Luton-ORD Chicago O'Hare Intl

15h 20m1 stop Reykjavik Keflavik Intl

$708Multiple Airlines

Sun, Nov 29 - Tue, Dec 8

6:30 pm - 3:10 pmORD Chicago O'Hare Intl-LGW London Gatwick

14h 40m1 stop Reykjavik Keflavik Intl

8:00 am - 5:20 pmLGW London Gatwick-ORD Chicago O'Hare Intl

15h 20m1 stop Reykjavik Keflavik Intl

$708Multiple Airlines

Tue, Mar 2 - Sun, Mar 7

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

14h 50m1 stop Kastrup Copenhagen

10:20 am - 4:45 pmLHR London Heathrow-ORD Chicago O'Hare Intl

12h 25m1 stop Kastrup Copenhagen

$711Scandinavian Airlines

Thu, Feb 11 - Sun, Feb 14

7:10 pm - 9:20 pmORD Chicago O'Hare Intl-LHR London Heathrow

20h 10m3 stops Kastrup Copenhagen Stockholm Arlanda Oslo Gardermoen

9:05 pm - 4:45 pmLHR London Heathrow-ORD Chicago O'Hare Intl

25h 40m2 stops Stockholm Arlanda Kastrup Copenhagen

$712Scandinavian Airlines

Sun, Nov 29 - Tue, Dec 8

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

10h 20m1 stop Reykjavik Keflavik Intl

12:15 pm - 5:20 pmLHR London Heathrow-ORD Chicago O'Hare Intl

11h 05m1 stop Reykjavik Keflavik Intl

$721Icelandair

Tue, Nov 10 - Thu, Dec 10

7:25 pm - 10:50 amORD Chicago O'Hare Intl-LHR London Heathrow

9h 25m1 stop Reykjavik Keflavik Intl

12:15 pm - 5:20 pmLHR London Heathrow-ORD Chicago O'Hare Intl

35h 05m1 stop Reykjavik Keflavik Intl

$730Icelandair

Mon, Apr 12 - Wed, Apr 14

9:40 pm - 3:40 pmORD Chicago O'Hare Intl-LHR London Heathrow

12h 00m1 stop Munich Franz Josef Strauss

1:30 pm - 7:55 pmLHR London Heathrow-ORD Chicago O'Hare Intl

12h 25m1 stop Frankfurt am Main

$732Lufthansa

Tue, Feb 2 - Thu, Feb 4

4:20 pm - 5:45 pmORD Chicago O'Hare Intl-LHR London Heathrow

19h 25m1 stop Frankfurt am Main

7:40 am - 6:25 pmLHR London Heathrow-ORD Chicago O'Hare Intl

16h 45m1 stop Munich Franz Josef Strauss

$732Lufthansa

Mon, Apr 5 - Wed, Apr 7

9:30 pm - 11:55 amORD Chicago O'Hare Intl-LHR London Heathrow

8h 25mnonstop

8:45 am - 3:55 pmLHR London Heathrow-ORD Chicago O'Hare Intl

13h 10m1 stop Zurich

$737United Airlines

Tue, Apr 6 - Thu, Apr 8

9:30 pm - 11:55 amORD Chicago O'Hare Intl-LHR London Heathrow

8h 25mnonstop

8:45 am - 3:55 pmLHR London Heathrow-ORD Chicago O'Hare Intl

13h 10m1 stop Zurich

$737United Airlines

Recent last minute flight deals from Illinois to London

Sat, Oct 31 - Mon, Nov 2

8:10 pm - 4:25 pmORD Chicago O'Hare Intl-LHR London Heathrow

15h 15m2 stops Kastrup Copenhagen Oslo Gardermoen

10:20 am - 4:45 pmLHR London Heathrow-ORD Chicago O'Hare Intl

12h 25m1 stop Kastrup Copenhagen

$738Scandinavian Airlines

Sun, Nov 1 - Thu, Nov 12

3:55 pm - 10:25 amORD Chicago O'Hare Intl-STN London Stansted

12h 30m1 stop Dublin

7:50 pm - 3:30 pmSTN London Stansted-ORD Chicago O'Hare Intl

25h 40m2 stops Malaga Lisbon Humberto Delgado

$755Multiple Airlines

Sun, Nov 1 - Mon, Nov 9

6:30 pm - 10:45 pmORD Chicago O'Hare Intl-STN London Stansted

22h 15m2 stops Reykjavik Keflavik Intl Dublin

10:35 pm - 5:20 pmSTN London Stansted-ORD Chicago O'Hare Intl

24h 45m2 stops Dublin Reykjavik Keflavik Intl

$764Multiple Airlines

Sun, Nov 1 - Tue, Dec 1

7:10 pm - 5:40 pmORD Chicago O'Hare Intl-LHR London Heathrow

16h 30m1 stop Kastrup Copenhagen

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

16h 05m1 stop Kastrup Copenhagen

$781Scandinavian Airlines

Sun, Nov 1 - Tue, Nov 3

8:10 pm - 8:35 pmORD Chicago O'Hare Intl-LGW London Gatwick

18h 25m2 stops Lisbon Humberto Delgado Porto

4:35 pm - 3:30 pmLGW London Gatwick-ORD Chicago O'Hare Intl

28h 55m1 stop Lisbon Humberto Delgado

$820TAP AIR PORTUGAL

Sun, Nov 1 - Tue, Mar 9

8:10 pm - 12:40 pmORD Chicago O'Hare Intl-LHR London Heathrow

34h 30m1 stop Lisbon Humberto Delgado

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

27h 00m1 stop Lisbon Humberto Delgado

$831TAP AIR PORTUGAL

Wed, Oct 28 - Fri, Nov 6

7:50 pm - 4:20 pmORD Chicago O'Hare Intl-LHR London Heathrow

15h 30m1 stop Zurich

6:00 am - 4:15 pmLHR London Heathrow-ORD Chicago O'Hare Intl

16h 15m1 stop Zurich

$882SWISS

Wed, Oct 28 - Thu, Nov 5

7:50 pm - 1:00 pmORD Chicago O'Hare Intl-LHR London Heathrow

12h 10m1 stop Zurich

9:00 am - 4:15 pmLHR London Heathrow-ORD Chicago O'Hare Intl

13h 15m1 stop Zurich

$882SWISS

Tue, Oct 27 - Tue, Nov 3

7:30 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

$906Icelandair

Tue, Oct 27 - Wed, Nov 11

7:30 pm - 10:55 amORD Chicago O'Hare Intl-LGW London Gatwick

10h 25m1 stop Reykjavik Keflavik Intl

11:55 am - 5:20 pmLGW London Gatwick-ORD Chicago O'Hare Intl

11h 25m1 stop Reykjavik Keflavik Intl

$1,253Icelandair

Recent direct flight deals from Illinois to London

Wed, Apr 21 - Sun, May 2

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

8h 00mnonstop

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

8h 40mnonstop

$763British Airways

Fri, Nov 13 - Sat, Nov 28

9:50 pm - 11:35 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

$775British Airways

Wed, Mar 3 - Tue, Mar 9

9:50 pm - 11:35 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

$867Iberia

Tue, Feb 9 - Wed, Feb 17

9:50 pm - 11:35 amORD Chicago O'Hare Intl-LHR London Heathrow

7h 45mnonstop

12:35 pm - 3:30 pmLHR London Heathrow-ORD Chicago O'Hare Intl

8h 55mnonstop

$867Iberia

Tue, Jan 26 - Tue, Feb 2

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

7h 45mnonstop

12:35 pm - 3:30 pmLHR London Heathrow-ORD Chicago O'Hare Intl

8h 55mnonstop

$867Finnair

Sun, Jan 24 - Wed, Jan 27

9:50 pm - 11:35 amORD Chicago O'Hare Intl-LHR London Heathrow

7h 45mnonstop

3:40 pm - 6:45 pmLHR London Heathrow-ORD Chicago O'Hare Intl

9h 05mnonstop

$868Finnair

Wed, Mar 3 - Tue, Mar 9

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

7h 45mnonstop

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

8h 45mnonstop

$893American Airlines

Tue, Feb 9 - Wed, Feb 17

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

7h 45mnonstop

12:35 pm - 3:30 pmLHR London Heathrow-ORD Chicago O'Hare Intl

8h 55mnonstop

$893American Airlines

Sun, Jan 24 - Thu, Jan 28

9:50 pm - 12:00 pmORD Chicago O'Hare Intl-LHR London Heathrow

8h 10mnonstop

1:35 pm - 4:55 pmLHR London Heathrow-ORD Chicago O'Hare Intl

9h 20mnonstop

$903United Airlines

Tue, Jan 26 - Thu, Jan 28

5:45 pm - 7:55 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

$903United Airlines

Useful Info

Low season	February
High season	March
Cheapest flight	$316

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 Stansted 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

Eastbourne

Ilford

Kingston upon Thames

Guildford

Bedford

Crawley

Watford

Harrow

Twickenham

Ipswich

St. Albans

Folkestone

Colchester

Woodbridge

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$316 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

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Cheapest flight

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

FAQs for booking flights from Illinois to London

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

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