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 round-trip 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>

$151 CHEAP FLIGHTS from Illinois to London

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

...and more

Travelers love KAYAK

41,299,237 searches in the past 7 days on KAYAK

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

Cheapest round-trip

$517

Overall average: $498

Multiple Airlines

Wed 2/11Wed 2/18

ORD - LGW • 1 stop

Cheapest non-stop

$580

Typical prices: $647-$847

Finnair

Mon 2/23Thu 3/5

ORD - LHR • Non-stop

Start a new search

KAYAK searches 100s 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 round-trip flight deals from Illinois to London

Wed, Feb 11 - Wed, Feb 18

9:00 pm - 6:55 pm

ORD

LGW

15h 55m

1 stop

8:50 am - 7:15 pm

LGW

ORD

16h 25m

1 stop

$517Multiple Airlines

Tue, Apr 7 - Tue, May 12

7:25 pm - 11:55 am

ORD

LHR

10h 30m

1 stop

1:05 pm - 6:15 pm

LHR

ORD

11h 10m

1 stop

$518Icelandair

Sun, Feb 15 - Wed, Feb 25

6:30 pm - 10:55 am

ORD

LGW

10h 25m

1 stop

11:55 am - 5:20 pm

LGW

ORD

11h 25m

1 stop

$518Icelandair

Wed, Apr 15 - Tue, Apr 28

6:00 pm - 2:00 pm

ORD

LGW

14h 00m

1 stop

9:15 pm - 4:00 pm

LGW

ORD

24h 45m

2 stops

$528TAP AIR PORTUGAL

Wed, Feb 18 - Tue, Feb 24

6:50 pm - 12:55 pm

ORD

LCY

12h 05m

1 stop

9:15 am - 4:20 pm

LCY

ORD

13h 05m

1 stop

$590SWISS

Wed, Feb 18 - Wed, Feb 25

6:50 pm - 12:55 pm

ORD

LCY

12h 05m

1 stop

9:20 am - 4:20 pm

LCY

ORD

13h 00m

1 stop

$591SWISS

Sat, Apr 25 - Tue, May 12

4:05 pm - 6:35 am

STL

LHR

32h 30m

1 stop

2:10 pm - 8:04 pm

LHR

STL

11h 54m

1 stop

$627Air Canada

Mon, Mar 30 - Wed, Apr 8

4:05 pm - 9:35 am

STL

LHR

11h 30m

1 stop

2:05 pm - 3:24 pm

LHR

STL

31h 19m

2 stops

$630Air Canada

Mon, Mar 9 - Wed, Mar 18

11:22 am - 9:00 am

STL

LGW

16h 38m

2 stops

12:30 pm - 12:43 pm

LGW

STL

29h 13m

2 stops

$631American Airlines

Sun, Mar 8 - Sun, Mar 15

9:15 am - 9:00 am

STL

LGW

18h 45m

2 stops

12:30 pm - 10:32 am

LGW

STL

27h 02m

2 stops

$672American Airlines

Useful Info

Low season	January
High season	March
Cheapest flight	$151

Best time to beat the crowds with an average 23% drop in price.

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 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

Slough

Hayes

Wembley

Richmond

Luton

Ilford

Crawley

Watford

Eastbourne

Guildford

Kingston upon Thames

Colchester

St. Albans

Twickenham

Ipswich

Bedford

Barnet

Hastings

Harrow

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 $4,620

Business Class flights to Londonfrom $2,385

Premium Economy Class flights to Londonfrom $1,476

Economy Class flights to Londonfrom $498

$151 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 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

Good to know

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 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.

Traveling 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 rental

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