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

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 Heathrow Airport. Visit our flight page for the latest deals!>/a>

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

KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to London Heathrow Airport from Illinois is likely to change within 7 days, so travellers know whether to wait or book now. Visit our flight page for the latest deals!>/a>

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

Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional return ticket. You could then fly to London Heathrow Airport with an airline and back to Illinois with another airline. Visit our flight page for the latest deals!>/a>

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

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 Heathrow Airport from Illinois up to 3 days before/after your preferred dates. You can then pick the flights that suit you best. Visit our flight page for the latest deals!>/a>

£205 CHEAP FLIGHTS from Illinois to London Heathrow (LHR)

KAYAK searches hundreds of travel sites at once for deals on flights to London Heathrow Airport

...and more

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Filter your dealsChoose cabin class, free Wi-Fi and more.

Cheapest return fare

£408

Overall average: £540

Scandinavian Airlines

Mon 2/3Thu 5/3

ORD - LHR • 1 stop

Cheapest direct flights

£464

Typical prices: £501-£685

British Airways

Mon 19/1Mon 26/1

ORD - LHR • Direct

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KAYAK searches hundreds of sites at once to find you the best travel deals.

We hope you love your trip to Heathrow!

Flight Deals

Cheap Flights from Illinois to Heathrow

Here are some of the best deals found on KAYAK recently from the most popular airlines for return flights from Illinois to Heathrow that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.

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

Round-trip

One-way

Last minute

Direct

Recent return flight deals from Illinois to Heathrow

Mon, 2 Mar - Thu, 5 Mar

19:20 - 16:00

ORD

LHR

14h 40m1 stop

10:20 - 16:45

LHR

ORD

12h 25m1 stop

£408Scandinavian Airlines

Tue, 6 Jan - Wed, 14 Jan

18:30 - 19:30

ORD

LHR

19h 00m1 stop

12:15 - 17:20

LHR

ORD

11h 05m1 stop

£409Icelandair

Mon, 12 Jan - Sat, 17 Jan

19:20 - 18:50

ORD

LHR

17h 30m2 stops

06:40 - 16:45

LHR

ORD

16h 05m2 stops

£410Scandinavian Airlines

Fri, 16 Jan - Tue, 20 Jan

20:15 - 17:30

ORD

LHR

15h 15m1 stop

18:30 - 15:00

LHR

ORD

26h 30m1 stop

£413TAP AIR PORTUGAL

Mon, 12 Jan - Wed, 15 Apr

17:29 - 11:15

MLI

LHR

11h 46m1 stop

07:25 - 16:59

LHR

MLI

15h 34m2 stops

£463Lufthansa

Mon, 12 Jan - Wed, 15 Apr

17:29 - 15:50

MLI

LHR

16h 21m2 stops

06:55 - 16:59

LHR

MLI

16h 04m2 stops

£469Lufthansa

Mon, 2 Feb - Mon, 9 Feb

06:15 - 07:50

EVV

LHR

19h 35m1 stop

06:30 - 17:19

LHR

EVV

16h 49m2 stops

£470KLM

Tue, 3 Feb - Tue, 10 Feb

05:51 - 06:25

MLI

LHR

18h 34m1 stop

06:30 - 16:28

LHR

MLI

15h 58m2 stops

£470Delta

Sun, 1 Feb - Sun, 8 Feb

15:35 - 09:00

BMI

LHR

11h 25m1 stop

06:30 - 22:08

LHR

BMI

21h 38m2 stops

£470Delta

Tue, 3 Feb - Tue, 10 Feb

18:14 - 11:40

MDW

LHR

11h 26m1 stop

08:55 - 17:29

LHR

MDW

14h 34m1 stop

£489KLM

Useful Info

Low season	February
High season	July
Cheapest flight	£205

Best time to beat the crowds (7% less expensive on average)

Most popular time to fly (9% more expensive on average)

Flight from St. Louis to London Heathrow Airport

Verified travelerFlew with British Airways

ORD

LHR

Jun 2025

Get a wheel chair if you have difficulty walking

JoeFlew with Iberia

ORD

LHR

Apr 2025

Get there early. Nice airport options while you wait.

Verified travelerFlew with Iberia

ORD

LHR

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

ORD

LHR

Jan 2025

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

KariFlew with British Airways

ORD

LHR

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

ORD

LHR

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 Heathrow Airport?
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 Heathrow Airport.
How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Illinois to London Heathrow Airport?
KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to London Heathrow Airport from Illinois is likely to change within 7 days, so travellers know whether to wait or book now.
What is the Hacker Fare option on flights from Illinois to London Heathrow Airport?
Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional return ticket. You could then fly to London Heathrow Airport 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 Heathrow Airport?
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 Heathrow Airport from Illinois up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

Gatwick

Milton Keynes

Eastbourne

Hounslow

Luton

Southend-on-Sea

Swindon

Northampton

Slough

Winchester

Croydon

Stansted

Poole

Folkestone

Chichester

Maidstone

Salisbury

Colchester

Chelmsford

Crawley

Everything you need to know for your flight to Heathrow

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London Heathrow Airport (LHR)

£205 Find Cheap Flights from Illinois to London Heathrow Airport

KAYAK searches hundreds of travel sites at once for deals on flights to London Heathrow Airport

Everything you should know

Cheap Flights from Illinois to Heathrow

Recent return flight deals from Illinois to Heathrow

Recent one-way flight deals from Illinois to Heathrow

Recent last minute flight deals from Illinois to Heathrow

Recent direct flight deals from Illinois to Heathrow

Good to know - Cheap tickets from Illinois to London Heathrow Airport

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

FAQs for booking Illinois to London Heathrow Airport flights

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

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 Heathrow Airport.

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

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

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

Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional return ticket. You could then fly to London Heathrow Airport 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 Heathrow Airport?

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 Heathrow Airport from Illinois up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

Travelling to a place near Heathrow?

Everything you need to know for your flight to Heathrow

Information on your arrival and departure airports

Cabin class types available on flights to Heathrow

Complete your trip to Heathrow with a hotel stay or car hire

Find direct flights for Heathrow

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Flights from domestic origins to Illinois

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