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. 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?

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

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 return ticket. You could then fly to London 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?

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

£135 CHEAP FLIGHTS from Illinois to London

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

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Cheapest return fare

£378

Typical prices: £463-£634

Icelandair

Fri 24/4Fri 1/5

ORD - LHR • 1 stop

Cheapest direct flights

£462

Typical prices: £471-£623

Finnair

Wed 25/2Tue 3/3

ORD - LHR • Direct

Start a new search

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

We hope you love your trip to London!

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 return flight deals from Illinois to London

Fri, 24 Apr - Fri, 1 May

22:25 - 20:20

ORD

LHR

15h 55m

1 stop

21:25 - 18:15

LHR

ORD

26h 50m

1 stop

£378Icelandair

Fri, 27 Feb - Tue, 3 Mar

18:30 - 10:55

ORD

LGW

10h 25m

1 stop

11:55 - 17:20

LGW

ORD

11h 25m

1 stop

£378Icelandair

Sun, 8 Mar - Tue, 17 Mar

21:25 - 20:35

ORD

LGW

18h 10m

2 stops

16:35 - 16:00

LGW

ORD

28h 25m

1 stop

£378TAP AIR PORTUGAL

Wed, 25 Feb - Tue, 3 Mar

18:30 - 22:50

ORD

STN

22h 20m

2 stops

06:30 - 17:20

STN

ORD

16h 50m

2 stops

£378Multiple Airlines

Tue, 21 Apr - Sat, 2 May

19:25 - 20:20

ORD

LHR

18h 55m

1 stop

13:05 - 18:15

LHR

ORD

11h 10m

1 stop

£378Icelandair

Fri, 27 Feb - Thu, 5 Mar

18:30 - 18:20

ORD

STN

17h 50m

2 stops

06:30 - 17:20

STN

ORD

16h 50m

2 stops

£380Multiple Airlines

Sun, 1 Mar - Fri, 13 Mar

15:50 - 09:45

STL

LHR

11h 55m

1 stop

06:30 - 14:55

LHR

STL

13h 25m

1 stop

£451Lufthansa

Wed, 25 Feb - Tue, 3 Mar

18:50 - 12:55

ORD

LCY

12h 05m

1 stop

09:15 - 16:20

LCY

ORD

13h 05m

1 stop

£452SWISS

Sun, 15 Feb - Tue, 24 Feb

18:50 - 12:55

ORD

LCY

12h 05m

1 stop

09:15 - 16:20

LCY

ORD

13h 05m

1 stop

£454SWISS

Sun, 1 Mar - Fri, 13 Mar

18:55 - 18:35

STL

LHR

17h 40m

2 stops

06:30 - 18:00

LHR

STL

16h 30m

2 stops

£457Lufthansa

Useful Info

Low season	January
High season	March
Cheapest flight	£135

Best time to beat the crowds (27% less expensive on average)

Most popular time to fly and prices are also 15% lower on average.

Flight from St. Louis to London Gatwick 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?
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 return 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.

Gatwick

Milton Keynes

Eastbourne

Hounslow

Luton

Southend-on-Sea

Slough

Winchester

Croydon

Stansted

Folkestone

Maidstone

Chichester

Colchester

Chelmsford

Crawley

Richmond

Bedford

Hastings

Watford

Everything you need to know for your flight to London

Cabin class

Complete your trip

Direct flights

Flights to other cities

Origins

Other airports

Return flight deals

Cabin class types available on flights to Illinois

First Class flights to Londonfrom £3,872

Business Class flights to Londonfrom £2,673

Premium Economy Class flights to Londonfrom £1,154

Economy class flights to Londonfrom £429

£135 Find Cheap Flights from Illinois to London

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

Everything you should know

Cheap Flights from Illinois to London

Recent return 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 - Cheap tickets from Illinois to London

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

FAQs for booking flights from Illinois to London

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 return 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.

Travelling to a place near London?

Everything you need to know for your flight to London

Cabin class types available on flights to Illinois

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

Find direct flights for London

Flights to other popular destinations

Flights from domestic origins to London

Choose which airport to fly into in London

Find deals for your return flight