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 travelers 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 round-trip 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.

$305 CHEAP FLIGHTS from Illinois to London Heathrow (LHR)

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Cheap Flights from Illinois to Heathrow

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 Heathrow

Mon, Oct 12 - Wed, Oct 14

5:35 pm - 9:35 am

ORD

LHR

10h 00m

1 stop

6:00 am - 12:35 pm

LHR

ORD

12h 35m

1 stop

$716Multiple Airlines

Fri, Sep 11 - Fri, Sep 18

10:25 pm - 8:20 pm

ORD

LHR

15h 55m

1 stop

9:25 pm - 6:15 pm

LHR

ORD

26h 50m

1 stop

$718Icelandair

Sat, Nov 14 - Tue, Nov 17

7:15 pm - 2:35 pm

ORD

LHR

37h 20m

2 stops

9:55 am - 4:45 pm

LHR

ORD

36h 50m

2 stops

$720Scandinavian Airlines

Mon, Aug 31 - Wed, Sep 9

7:25 pm - 11:55 am

ORD

LHR

10h 30m

1 stop

1:05 pm - 6:15 pm

LHR

ORD

11h 10m

1 stop

$721Icelandair

Sun, Oct 18 - Tue, Oct 20

9:30 pm - 11:55 am

ORD

LHR

8h 25mnonstop

6:50 am - 12:00 pm

LHR

ORD

11h 10m

1 stop

$722United Airlines

Sun, Dec 6 - Wed, Dec 9

5:42 pm - 7:55 am

MLI

LHR

32h 13m

1 stop

7:30 am - 10:14 am

LHR

MLI

32h 44m

2 stops

$816United Airlines

Mon, Sep 28 - Sun, Oct 4

12:04 pm - 6:25 am

BMI

LHR

12h 21m

1 stop

1:25 pm - 10:34 pm

LHR

BMI

15h 09m

1 stop

$864Virgin Atlantic

Mon, Nov 23 - Thu, Nov 26

12:30 pm - 7:05 am

MDW

LHR

12h 35m

1 stop

6:30 am - 4:50 pm

LHR

MDW

16h 20m

2 stops

$865Delta

Mon, Oct 12 - Thu, Oct 15

5:21 pm - 1:05 pm

MDW

LHR

13h 44m

1 stop

6:30 am - 4:39 pm

LHR

MDW

16h 09m

2 stops

$866Delta

Tue, Oct 20 - Thu, Nov 12

9:29 am - 6:45 am

MDW

LHR

15h 16m

2 stops

8:40 am - 6:37 pm

LHR

MDW

15h 57m

2 stops

$870Virgin Atlantic

Useful Info

Low season	January
High season	July
Cheapest flight	$305

Best time to beat the crowds with an average 19% drop in price.

Most popular time to fly with an average 31% increase in price.

Flight from Chicago O'Hare Airport to London Heathrow Airport

Verified travelerFlew with British Airways

ORD

LHR

Mar 2026

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

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 travelers 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 round-trip 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.

Hounslow

Slough

Hayes

Richmond

Wembley

Salisbury

Luton

Crawley

Ilford

Eastbourne

Swindon

Watford

Northampton

Bedford

Colchester

Guildford

Ipswich

Kingston upon Thames

Twickenham

St. Albans

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London Heathrow Airport (LHR)

LHR

$305 Find Cheap Flights from Illinois to London Heathrow Airport - Compare and Save

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

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