£132 Find Cheap Flights from Illinois to the United Kingdom

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Good to know - Cheap tickets from Illinois to the United Kingdom

Low seasonFebruary
High seasonSeptember
Cheapest flight£132
Best time to beat the crowds (20% less expensive on average)
Most popular time to fly and prices are also 13% lower on average.
Flight from Chicago to London Gatwick Airport

Flights from Illinois to the United Kingdom: the best tips from KAYAK users

Insights shared by verified travellers who flew the route from Illinois to the United Kingdom 
Learn how KAYAK collects reviews and tips from users.
Verified travelerFlew with British AirwaysORD-LHRJun 2025
Get a wheel chair if you have difficulty walking
JoeFlew with IberiaORD-LHRApr 2025
Get there early. Nice airport options while you wait.
Verified travelerFlew with IberiaORD-LHRMay 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 AirlinesORD-LHRJan 2025
Anticipate delays, prepare for long walks through Heathrow to baggage claim or for connections.
KariFlew with British AirwaysORD-LHRMay 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 AirlinesORD-LHRDec 2023
Find a flight where you are allowed to choose your seats before the day of boarding for anything international.

FAQs for booking flights from Illinois to the United Kingdom

  • How does KAYAK find such low prices on flights from Illinois to the United Kingdom?

    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 the United Kingdom.

  • How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Illinois to the United Kingdom?

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight from Illinois to the United Kingdom 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 the United Kingdom?

    Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional return ticket. You could then fly from Illinois to the United Kingdom with an airline and back with another airline.

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Illinois to the United Kingdom?

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

  • Which is the cheapest airport to fly into in the United Kingdom?

    Prices will differ depending on the departure airport, but generally, the cheapest airport to fly to in the United Kingdom is London Heathrow Airport (LHR), with an average flight price of £352.

  • What is the cheapest day to fly to the United Kingdom?

    Based on KAYAK data, the cheapest day to fly to the United Kingdom is Wednesday when return tickets can be as cheap as £531. On the other hand, the most expensive day to fly is Saturday, when return prices are £664 on average.

  • What is the cheapest time of day to fly to the United Kingdom?

    The cheapest time of day to fly to the United Kingdom is generally in the evening, when round-trip flights cost £818 on average. Morning departures are around 5% more expensive than evening flights, on average. The most expensive time of day to fly to the United Kingdom is generally in the afternoon, which is peak travel time and where the average cost of a ticket is £933.

  • What is the cheapest flight to the United Kingdom?

    The cheapest ticket to the United Kingdom from Illinois found in the last 72 hours was to London Heathrow Airport, at £596 return. The most popular route is Chicago O'Hare Intl Airport (ORD) to London Heathrow Airport (LHR) and the cheapest return airline ticket found on this route in the last 72 hours was £596.

  • What is the cheapest month to fly from Illinois to the United Kingdom?

    The cheapest month for flights from Illinois to the United Kingdom is January, when tickets cost £409 (return) on average. On the other hand, the most expensive months are May and June, when the average cost of round-trip tickets is £888 and £740 respectively.

  • How far in advance should I book a flight from Illinois to the United Kingdom?

    To get a below-average price on the flight from Illinois to the United Kingdom, you should book around 1 week before departure. For the absolute cheapest price, our data suggests you should book 16 weeks before departure.

  • How long is the flight to the United Kingdom?

    An average direct flight from Illinois to the United Kingdom takes 12h 45m, covering a distance of 3884 miles. The shortest route is Chicago O'Hare Intl Airport (ORD) to London Heathrow Airport (LHR) with an average flight time of 7h 35m.

  • What are the most popular destinations in the United Kingdom?

    Based on KAYAK flight searches, the most popular destination is London (82% of total searches to the United Kingdom). The next most popular destinations are Belfast (8%) and Edinburgh (6%). Searches for flights to Manchester (2%), to Birmingham (1%), and to Leeds (0%) are also popular.

Book cheap flights from Illinois to the United Kingdom

Cheapest flights to the United Kingdom from Illinois found in 2025

Recent return flight deals

13/8Wed
1 stopSWISS
12h 30mORD-LCY
28/8Thu
1 stopSWISS
12h 30mLCY-ORD
£222
17/11Mon
2 stopsScandinavian Airlines
31h 35mORD-LHR
20/11Thu
1 stopScandinavian Airlines
16h 05mLHR-ORD
£273
7/8Thu
1 stop
18h 00mORD-LGW
29/8Fri
1 stop
14h 22mLGW-ORD
£326
7/8Thu
1 stop
18h 00mORD-LGW
29/8Fri
1 stop
32h 10mLGW-ORD
£327
6/11Thu
1 stopIcelandair
10h 25mORD-LGW
14/11Fri
1 stopIcelandair
11h 25mLGW-ORD
£349
26/11Wed
1 stopIcelandair
10h 25mORD-LGW
3/12Wed
1 stopIcelandair
11h 25mLGW-ORD
£352
17/8Sun
1 stopDelta
14h 35mORD-LGW
27/8Wed
1 stopDelta
15h 53mLGW-ORD
£365
19/8Tue
2 stopsVirgin Atlantic
16h 45mORD-LGW
4/9Thu
2 stopsVirgin Atlantic
16h 37mLGW-ORD
£368
3/8Sun
1 stopVirgin Atlantic
11h 49mMDW-LHR
12/8Tue
1 stopVirgin Atlantic
14h 39mLHR-MDW
£382
20/8Wed
1 stopDelta
12h 40mSTL-LHR
29/8Fri
2 stopsDelta
18h 46mLHR-STL
£385

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Recent one-way flight deals

21/7Mon
1 stop
16h 46mORD-LGW
£132
16/7Wed
1 stop
16h 46mORD-LGW
£135
7/8Thu
1 stopTAP AIR PORTUGAL
18h 50mORD-LHR
£160
3/10Fri
1 stopIcelandair
31h 40mORD-LHR
£162
2/8Sat
1 stopTAP AIR PORTUGAL
21h 45mORD-LHR
£164
30/9Tue
1 stopIcelandair
18h 55mORD-LHR
£168
21/9Sun
2 stopsScandinavian Airlines
17h 40mORD-EDI
£270
4/9Thu
2 stopsScandinavian Airlines
17h 40mORD-EDI
£271
7/8Thu
1 stopJetBlue
11h 43mORD-EDI
£273
16/8Sat
1 stopJetBlue
14h 55mORD-EDI
£280

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Last minute flights from Illinois to the United Kingdom

Last minute flight, train and bus deals

7/7Mon
multi-stop
41h 15mORD-LGW
23/9Tue
multi-stop
29h 18mLGW-ORD
£483
7/7Mon
multi-stop
35h 17mORD-LGW
23/9Tue
multi-stop
29h 18mLGW-ORD
£496
7/7Mon
directAmerican Airlines
7h 45mORD-LHR
23/9Tue
multi-stopAmerican Airlines
14h 05mLHR-ORD
£514
7/7Mon
multi-stopAmerican Airlines
12h 35mORD-LHR
23/9Tue
multi-stopAmerican Airlines
12h 55mLHR-ORD
£517
5/7Sat
directFinnair
7h 45mORD-LHR
8/4Wed
multi-stopFinnair
13h 30mLHR-ORD
£527
7/7Mon
directIberia
8h 05mORD-LHR
23/9Tue
directIberia
8h 35mLHR-ORD
£532
7/7Mon
multi-stopVirgin Atlantic
17h 24mMDW-LHR
23/9Tue
multi-stopVirgin Atlantic
21h 21mLHR-MDW
£538
7/7Mon
multi-stopVirgin Atlantic
15h 20mMDW-LHR
23/9Tue
multi-stopVirgin Atlantic
18h 20mLHR-MDW
£541
5/7Sat
directIberia
7h 45mORD-LHR
8/4Wed
directIberia
8h 35mLHR-ORD
£544
5/7Sat
directFinnair
7h 40mORD-LHR
8/4Wed
multi-stopFinnair
16h 20mLHR-ORD
£690

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Everything you need to know for your flight to the United Kingdom

Cabin class types available on flights to Illinois

Cabin classes available on flights to Illinois. Prices are the lowest found on KAYAK over the last 7 days. Price and availability is not guaranteed.
First Class flights to the United Kingdomfrom £3,905
Business Class flights to the United Kingdomfrom £2,941
Prem Econ Class flights to the United Kingdomfrom £1,730
Economy class flights to the United Kingdomfrom £436

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