£142 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£142
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 Heathrow 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 £493.

  • 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 £538. On the other hand, the most expensive day to fly is Saturday, when return prices are £657 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 £809 on average. Morning departures are around 7% 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 £601 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 £601.

  • 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 £412 (return) on average. On the other hand, the most expensive months are May and June, when the average cost of round-trip tickets is £893 and £745 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 13h 33m, covering a distance of 3878 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 (86% of total searches to the United Kingdom). The next most popular destinations are Edinburgh (8%) and Manchester (2%). Searches for flights to Belfast (1%), to Birmingham (1%), and to Bristol (1%) 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

5/12Fri
2 stopsScandinavian Airlines
32h 15mORD-LHR
8/12Mon
2 stopsScandinavian Airlines
16h 05mLHR-ORD
£272
5/12Fri
2 stopsScandinavian Airlines
35h 35mORD-LHR
8/12Mon
1 stopScandinavian Airlines
16h 05mLHR-ORD
£275
15/7Tue
1 stop
16h 51mORD-LGW
9/9Tue
1 stop
18h 47mLGW-ORD
£342
21/9Sun
1 stop
20h 55mORD-LGW
28/9Sun
1 stop
18h 47mLGW-ORD
£371
7/9Sun
1 stopBritish Airways
14h 20mORD-EDI
8/9Mon
2 stopsBritish Airways
25h 40mEDI-ORD
£390
7/9Sun
2 stopsBritish Airways
13h 33mORD-EDI
8/9Mon
2 stopsBritish Airways
24h 40mEDI-ORD
£394
9/9Tue
1 stopIcelandair
12h 00mORD-GLA
25/9Thu
1 stopIcelandair
9h 55mGLA-ORD
£403
11/9Thu
1 stopTAP AIR PORTUGAL
22h 55mORD-LHR
15/9Mon
1 stopTAP AIR PORTUGAL
16h 40mLHR-ORD
£407
15/9Mon
1 stopTAP AIR PORTUGAL
15h 25mORD-LGW
20/9Sat
1 stopTAP AIR PORTUGAL
29h 55mLGW-ORD
£408
28/10Tue
1 stopIcelandair
9h 25mORD-GLA
5/11Wed
1 stopIcelandair
10h 45mGLA-ORD
£408

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Recent one-way flight deals

15/11Sat
2 stops
28h 58mORD-LHR
£142
23/7Wed
1 stop
18h 29mORD-LGW
£145
8/10Wed
1 stopIcelandair
9h 10mORD-GLA
£156
26/10Sun
1 stopIcelandair
31h 05mORD-EDI
£156
25/7Fri
1 stopTAP AIR PORTUGAL
17h 45mORD-LHR
£162
17/7Thu
1 stopTAP AIR PORTUGAL
22h 55mORD-LHR
£163
10/7Thu
1 stopWestJet
34h 35mORD-EDI
£199
29/7Tue
1 stopJetBlue
15h 24mORD-LHR
£228
25/7Fri
1 stopJetBlue
15h 50mORD-LHR
£233
20/11Thu
1 stopWestJet
14h 05mORD-LHR
£275

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Last minute flights from Illinois to the United Kingdom

Last minute flight, train and bus deals

17/6Tue
multi-stop
27h 52mORD-EDI
24/6Tue
multi-stop
27h 37mEDI-ORD
£603
16/6Mon
multi-stop
24h 05mORD-STN
23/6Mon
multi-stop
30h 05mSTN-ORD
£621
16/6Mon
multi-stopJetBlue
15h 50mORD-LHR
27/6Fri
multi-stopJetBlue
17h 30mLHR-ORD
£641
17/6Tue
multi-stopUnited Airlines
21h 35mORD-EDI
24/6Tue
multi-stopUnited Airlines
28h 59mEDI-ORD
£657
17/6Tue
multi-stopUnited Airlines
13h 35mORD-EDI
24/6Tue
directUnited Airlines
8h 35mEDI-ORD
£660
17/6Tue
multi-stopAir Canada
14h 40mORD-EDI
27/6Fri
multi-stopAir Canada
28h 37mEDI-ORD
£662
17/6Tue
multi-stopAir Canada
28h 55mORD-EDI
26/6Thu
multi-stopAir Canada
28h 55mEDI-ORD
£667
17/6Tue
multi-stopBritish Airways
12h 10mORD-EDI
23/6Mon
multi-stopBritish Airways
22h 20mEDI-ORD
£669
14/6Sat
multi-stopJetBlue
14h 50mORD-LHR
18/6Wed
multi-stopJetBlue
13h 28mLHR-ORD
£715
17/6Tue
multi-stopBritish Airways
11h 00mORD-GLA
5/7Sat
multi-stopBritish Airways
12h 05mGLA-ORD
£971

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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 £3,931
Business Class flights to the United Kingdomfrom £2,961
Prem Econ Class flights to the United Kingdomfrom £1,741
Economy class flights to the United Kingdomfrom £442

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