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.

$322 CHEAP FLIGHTS from Illinois to London

Save 25% 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.

Cheap Flights from Illinois to London

Cheap flights from Illinois to London with top airlines, updated regularly. Compare round-trip, one-way, direct and last-minute deals.

Round-trip

One-way

Last minute

Direct

Sun, Nov 8 - Thu, Nov 19

6:30 pm - 3:05 pmORD Chicago O'Hare Intl-LTN London Luton

14h 35m1 stop Reykjavik Keflavik Intl

6:05 am - 5:20 pmLTN London Luton-ORD Chicago O'Hare Intl

17h 15m1 stop Reykjavik Keflavik Intl

$703Multiple Airlines

Wed, Dec 30 - Sat, Jan 9

8:05 pm - 11:20 pmORD Chicago O'Hare Intl-STN London Stansted

21h 15m1 stop Dublin

8:45 am - 5:20 pmSTN London Stansted-ORD Chicago O'Hare Intl

38h 35m2 stops Gdansk Rebiechowo Reykjavik Keflavik Intl

$703Multiple Airlines

Thu, Nov 19 - Mon, Nov 23

6:30 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

$707Icelandair

Thu, Nov 19 - Sun, Nov 22

6:30 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

$707Icelandair

Tue, Apr 13 - Fri, Apr 30

7:25 pm - 9:35 amORD Chicago O'Hare Intl-LHR London Heathrow

8h 10mnonstop

1:30 pm - 4:25 pmLHR London Heathrow-ORD Chicago O'Hare Intl

8h 55mnonstop

$707British Airways

Thu, Dec 10 - Fri, Dec 18

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

14h 50m1 stop Kastrup Copenhagen

7:30 pm - 4:45 pmLHR London Heathrow-ORD Chicago O'Hare Intl

27h 15m1 stop Kastrup Copenhagen

$709Scandinavian Airlines

Sun, Jan 17 - Thu, Jan 21

7:10 pm - 9:40 pmORD Chicago O'Hare Intl-LHR London Heathrow

20h 30m1 stop Kastrup Copenhagen

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

16h 05m1 stop Kastrup Copenhagen

$709Scandinavian Airlines

Wed, Nov 25 - Sun, Nov 29

1:55 pm - 7:10 amORD Chicago O'Hare Intl-LHR London Heathrow

11h 15m1 stop Montreal Pierre Elliott Trudeau Intl

11:10 am - 7:58 pmLHR London Heathrow-ORD Chicago O'Hare Intl

14h 48m1 stop Toronto Pearson Intl

$719Air Canada

Tue, Feb 2 - Thu, Feb 4

8:58 am - 11:50 amORD Chicago O'Hare Intl-LHR London Heathrow

20h 52m1 stop Vancouver Intl

6:00 am - 7:52 pmLHR London Heathrow-ORD Chicago O'Hare Intl

19h 52m2 stops Zurich Montreal Pierre Elliott Trudeau Intl

$734Air Canada

Wed, Nov 18 - Mon, Nov 23

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

$779British Airways

Wed, Oct 21 - Tue, Nov 10

6:00 pm - 10:55 pmORD Chicago O'Hare Intl-LHR London Heathrow

22h 55m1 stop Lisbon Humberto Delgado

8:50 pm - 3:30 pmLHR London Heathrow-ORD Chicago O'Hare Intl

24h 40m2 stops Barcelona-El Prat Lisbon Humberto Delgado

$721Multiple Airlines

Thu, Oct 22 - Wed, Nov 18

6:00 pm - 8:25 pmORD Chicago O'Hare Intl-LGW London Gatwick

20h 25m2 stops Lisbon Humberto Delgado Porto

7:00 am - 5:20 pmLGW London Gatwick-ORD Chicago O'Hare Intl

16h 20m2 stops Kastrup Copenhagen Reykjavik Keflavik Intl

$755Multiple Airlines

Sun, Oct 25 - Sat, Oct 31

8:10 pm - 9:40 pmORD Chicago O'Hare Intl-LHR London Heathrow

20h 30m1 stop Kastrup Copenhagen

6:40 am - 5:45 pmLHR London Heathrow-ORD Chicago O'Hare Intl

16h 05m1 stop Kastrup Copenhagen

$765Scandinavian Airlines

Sun, Oct 25 - Sat, Oct 31

8:10 pm - 9:35 pmORD Chicago O'Hare Intl-LHR London Heathrow

20h 25m2 stops Kastrup Copenhagen Oslo Gardermoen

6:40 am - 5:45 pmLHR London Heathrow-ORD Chicago O'Hare Intl

16h 05m1 stop Kastrup Copenhagen

$768Scandinavian Airlines

Wed, Oct 21 - Wed, Nov 4

6:00 pm - 10:00 pmORD Chicago O'Hare Intl-LHR London Heathrow

22h 00m1 stop Lisbon Humberto Delgado

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

15h 30m1 stop Lisbon Humberto Delgado

$788TAP AIR PORTUGAL

Wed, Oct 21 - Tue, Nov 10

6:00 pm - 10:00 pmORD Chicago O'Hare Intl-LHR London Heathrow

22h 00m1 stop Lisbon Humberto Delgado

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

27h 00m1 stop Lisbon Humberto Delgado

$791TAP AIR PORTUGAL

Sun, Oct 25 - Thu, Oct 29

7:30 pm - 10:50 amORD Chicago O'Hare Intl-LHR London Heathrow

10h 20m1 stop Reykjavik Keflavik Intl

8:35 pm - 6:20 pmLHR London Heathrow-ORD Chicago O'Hare Intl

26h 45m1 stop Reykjavik Keflavik Intl

$863Icelandair

Tue, Oct 20 - Tue, Oct 27

2:40 pm - 11:20 amORD Chicago O'Hare Intl-LHR London Heathrow

14h 40m1 stop Zurich

6:00 am - 5:15 pmLHR London Heathrow-ORD Chicago O'Hare Intl

16h 15m1 stop Zurich

$879SWISS

Wed, Oct 21 - Thu, Oct 29

2:20 pm - 7:55 amORD Chicago O'Hare Intl-LHR London Heathrow

11h 35m1 stop Zurich

6:00 am - 5:15 pmLHR London Heathrow-ORD Chicago O'Hare Intl

16h 15m1 stop Zurich

$880SWISS

Fri, Oct 23 - Fri, Oct 30

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

13h 15m1 stop Reykjavik Keflavik Intl

11:55 am - 6:20 pmLGW London Gatwick-ORD Chicago O'Hare Intl

11h 25m1 stop Reykjavik Keflavik Intl

$896Icelandair

Tue, Apr 13 - Fri, Apr 30

7:25 pm - 9:35 amORD Chicago O'Hare Intl-LHR London Heathrow

8h 10mnonstop

1:30 pm - 4:25 pmLHR London Heathrow-ORD Chicago O'Hare Intl

8h 55mnonstop

$707British Airways

Wed, Nov 18 - Mon, Nov 23

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

$779British Airways

Mon, Jan 25 - Fri, Jan 29

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

$865Iberia

Mon, Feb 1 - Thu, Feb 25

9:50 pm - 11:35 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

$865Iberia

Wed, Mar 10 - Tue, Mar 23

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

7h 45mnonstop

4:30 pm - 8:15 pmLHR London Heathrow-ORD Chicago O'Hare Intl

8h 45mnonstop

$866Finnair

Tue, Apr 6 - Tue, Apr 13

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

$870Finnair

Wed, Mar 24 - Tue, Mar 30

4:45 pm - 5:55 amORD Chicago O'Hare Intl-LHR London Heathrow

8h 10mnonstop

8:00 am - 10:55 amLHR London Heathrow-ORD Chicago O'Hare Intl

8h 55mnonstop

$892United Airlines

Sun, Mar 21 - Wed, Mar 24

10:50 pm - 12:00 pmORD Chicago O'Hare Intl-LHR London Heathrow

8h 10mnonstop

1:35 pm - 5:55 pmLHR London Heathrow-ORD Chicago O'Hare Intl

9h 20mnonstop

$892United Airlines

Tue, Mar 2 - Wed, Mar 17

5:10 pm - 6:55 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

$892American Airlines

Wed, Mar 10 - Wed, Mar 24

5:10 pm - 6:55 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

$892American Airlines

Low season	February
High season	March
Cheapest flight	$322

Best time to beat the crowds with an average 22% drop in price.

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

Flight from Chicago to London Luton 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

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

$322 Find Cheap Flights from Illinois to London - Compare and Save

Cheap Flights from Illinois to London

Cheap flights from Illinois to London with top airlines, updated regularly. Compare round-trip, one-way, direct and last-minute deals.

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