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$218+ Cheap flights from Illinois to London (LON)

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 8/1. Fares are subject to change and may not be available on all flights or dates of travel.
ORD — LON
Aug 15 — Aug 221
Sat 8/15
Sat 8/22
1 adult, Economy
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Cheap flight deals from Illinois to London

Cheapest flights from Illinois to London
Explore the most affordable flight options available from Illinois to London. Find the lowest fares from popular airlines and budget airlines, with prices last updated on July 16, 2026.

This Justfly.com deal was found by Cheapflights users on 7/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Justfly.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/67:25 pm
ORD
-
LHR
1 stop10h 30m
Icelandair
Thu 11/1212:15 pm
LHR
-
ORD
1 stop11h 05m
Icelandair
Deal found 7/15$711
This Kiwi.com deal was found by Cheapflights users on 7/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/510:25 pm
ORD
-
LGW
1 stop10h 10m
Multiple Airlines
Sat 9/122:00 pm
LGW
-
ORD
1 stop15h 55m
Multiple Airlines
Deal found 7/15$711
This Kiwi.com deal was found by Cheapflights users on 7/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/147:25 pm
ORD
-
LHR
1 stop10h 30m
Icelandair
Tue 9/229:25 pm
LHR
-
ORD
1 stop26h 50m
Icelandair
Deal found 7/15$712
This Kiwi.com deal was found by Cheapflights users on 7/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/1710:16 am
ORD
-
LGW
1 stop17h 44m
Multiple Airlines
Mon 8/242:00 pm
LGW
-
ORD
1 stop15h 08m
Multiple Airlines
Deal found 7/15$712
This Kiwi.com deal was found by Cheapflights users on 7/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/110:25 pm
ORD
-
LHR
1 stop15h 55m
Icelandair
Thu 9/109:25 pm
LHR
-
ORD
1 stop26h 50m
Icelandair
Deal found 7/16$713
This Kiwi.com deal was found by Cheapflights users on 7/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 8/237:25 pm
ORD
-
LGW
1 stop13h 15m
Icelandair
Tue 9/13:40 pm
LGW
-
ORD
1 stop11h 45m
Icelandair
Deal found 7/15$713
This Mytrip deal was found by Cheapflights users on 7/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/77:25 pm
ORD
-
STN
3 stops22h 45m
Multiple Airlines
Tue 10/139:00 pm
STN
-
ORD
2 stops25h 10m
Multiple Airlines
Deal found 7/15$713
This Kiwi.com deal was found by Cheapflights users on 7/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/2610:25 pm
ORD
-
LHR
1 stop15h 55m
Icelandair
Sat 9/59:25 pm
LHR
-
ORD
1 stop26h 50m
Icelandair
Deal found 7/15$714
This Kiwi.com deal was found by Cheapflights users on 7/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/1012:44 am
ORD
-
LGW
2 stops27h 16m
Multiple Airlines
Thu 8/272:00 pm
LGW
-
ORD
1 stop15h 08m
Multiple Airlines
Deal found 7/15$714
This Mytrip deal was found by Cheapflights users on 7/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 11/136:30 pm
ORD
-
STN
2 stops15h 25m
Multiple Airlines
Thu 11/197:55 am
STN
-
ORD
2 stops15h 25m
Multiple Airlines
Deal found 7/15$714
This Icelandair deal was found by Cheapflights users on 7/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Icelandair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/510:25 pm
ORD
-
LHR
1 stop31h 30m
Icelandair
Thu 9/109:25 pm
LHR
-
ORD
1 stop30h 00m
Icelandair
Deal found 7/15$715
This Norse deal was found by Cheapflights users on 7/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Norse is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/1710:16 am
ORD
-
LGW
1 stop17h 44m
Multiple Airlines
Tue 8/252:00 pm
LGW
-
ORD
1 stop15h 08m
Multiple Airlines
Deal found 7/15$715

Find flight deals from Illinois to London

Keep the following information in mind while searching for Illinois to London flight deals. Data was last updated July 16, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$711
(Justfly.com)

One-way from

$218
(Kiwi.com)

Popular in

June

Cheapest in

September

Average price

$969

Good round-trip deal

$1,010 or less

Good one-way deal

$391 or less
Provider with most accurate pricing for Chicago (CHI)-London (LON) flight deals.
Search Deals
Provider most trusted by Cheapflights users for Chicago (CHI)-London (LON) flights.
Search Deals
From Illinois to London (LON)
Search Deals
One-way flight from Illinois to London (LON)
Search Deals
Highest demand for flights based on searches. 26% potential increase in price ($289 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 7% potential price decrease ($54 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in July 2026
Search Deals
Price to beat on a round-trip flight from Illinois to London (LON).
Search Deals
Price to beat on a one-way flight from Illinois to London (LON).
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from Illinois to London that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated July 16, 2026.
Use the filters below to find and compare flights from Illinois to London that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

ChicagoLondon

ORD - LTN

ORDLTN

Chicago O'Hare Intl

Fri 8/28

9:00 pm-5:25 pm

1 stop14h 25m

London Luton

Fri 9/4

6:20 am-2:00 pm

1 stop13h 40m

$760

ChicagoLondon

ORD - LTN

ORDLTN

Chicago O'Hare Intl

Mon 9/21

7:25 pm-10:05 pm

2 stops20h 40m

London Luton

Tue 9/29

9:30 am-6:15 pm

2 stops14h 45m

$780

ChicagoLondon

ORD - LTN

ORDLTN

Chicago O'Hare Intl

Tue 8/11

3:45 pm-9:15 am

1 stop11h 30m

London Luton

Tue 8/18

1:10 pm-7:15 pm

1 stop12h 05m

$785

ChicagoLondon

ORD - LHR

ORDLHR

Chicago O'Hare Intl

Wed 11/4

6:50 pm-8:05 am

1 stop31h 15m

London Heathrow

Sat 11/7

7:40 am-10:45 am

Nonstop9h 05m

$799

ChicagoLondon

ORD - LTN

ORDLTN

Chicago O'Hare Intl

Wed 8/5

3:40 pm-3:25 pm

2 stops17h 45m

London Luton

Wed 8/12

6:15 am-2:55 pm

2 stops14h 40m

$801

ChicagoLondon

ORD - LTN

ORDLTN

Chicago O'Hare Intl

Thu 9/3

5:10 pm-8:40 pm

2 stops21h 30m

London Luton

Mon 9/7

3:30 pm-3:10 pm

2 stops29h 40m

$802

ChicagoLondon

ORD - STN

ORDSTN

Chicago O'Hare Intl

Thu 11/26

8:15 pm-9:55 am

1 stop31h 40m

London Stansted

Thu 12/3

5:20 pm-6:20 pm

1 stop31h 00m

$833

ChicagoLondon

ORD - STN

ORDSTN

Chicago O'Hare Intl

Tue 10/6

11:25 am-9:55 am

1 stop16h 30m

London Stansted

Tue 10/13

5:35 pm-6:15 pm

1 stop30h 40m

$833

ChicagoLondon

ORD - LGW

ORDLGW

Chicago O'Hare Intl

Tue 9/15

11:25 am-10:25 pm

1 stop29h 00m

London Gatwick

Tue 10/13

7:00 am-9:40 am

1 stop32h 40m

$841

ChicagoLondon

ORD - STN

ORDSTN

Chicago O'Hare Intl

Wed 11/25

11:45 am-4:20 pm

1 stop22h 35m

London Stansted

Mon 11/30

10:55 am-10:00 am

1 stop29h 05m

$873

Flights are sorted by cheapest round-trip flights first.

Deals found on 7/11

Showing 1-10 of 60 resultsSorted by cheapest first
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Best time to book a flight from Illinois to London

Have a flexible travel schedule? Discover the best time to fly to London from Illinois with our price prediction graph.
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Cheapflights Insights

Everything you need to know about your flight from Illinois to London

What is the cheapest month to book a flight from Illinois to London?

Currently, September is the cheapest month in which you can book a flight from Illinois to London (average of $655). Flying from Illinois to London in February is currently the most expensive (average of $1,627). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

What is the cheapest time of day to fly from IL to LON?

Find hourly flight availability from Illinois to London. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated July 16, 2026.

Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Illinois to London as you normally would.

Weekly flight availability from Illinois to London

Explore weekly flight availability from Illinois to London. Discover flights operating on different days of the week, giving you the flexibility to choose a travel day that best fits your plans. Compare info to find the most convenient option for your journey. Data last updated July 16, 2026.

The most flights from USIL to LON are scheduled on a Monday (57 on average). You will have fewer flight options on Monday, which is when the least amount of flights are scheduled (57 on average).

How much does it cost to fly round-trip from Illinois to London?

How far ahead should I book a flight from Illinois to London?

To ensure you get the cheapest price possible for a flight from Illinois to London, you should look to book at least 32 days in advance of your intended travel date. The price of your flight may increase if you delay and leave booking until a week or so before departure.

Related info for your journey

Find useful and relevant information for your journey from Illinois to London. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • How long is the flight from Illinois to London?

    For as low as $711, Icelandair can have you in London from Illinois in 10h 30m. The distance between Illinois and London is about 3939 mi. Both multi-stop and nonstop flights can be found to your destination and back.

  • What are the cheapest airlines to fly from Illinois to London one-way?

    For one-way options, check prices for JetBlue. According to our data, you can fly for as low as $135. Users have also found prices from $229 and $279 on Icelandair and Finnair, respectively.

  • What are the most popular routes from Illinois to London?

    While some choose either Chicago O'Hare Intl - London Gatwick or Chicago O'Hare Intl - London Stansted, Chicago O'Hare Intl - London Heathrow is the most popular route from Illinois to London.

  • What are the most reliable airlines from Illinois to London?

    No one likes to see their flight delayed. When booking a flight from Illinois to London consider choosing SriLankan Airlines (74%), Gulf Air (69%) or Malaysia Airlines (69%) as they are the most reliable in getting you off to your destination on time.

  • What are the cheapest flights from Illinois to London?

    On average you can expect to pay $3,126 for a flight from Illinois to London. The cheapest flight overall is $324 while the most popular route, (Chicago O'Hare Intl - London Heathrow) is currently priced at $535.

  • Can I find deals for flights from Illinois to London that include hotel bookings?

    Yes. In addition to deals on Illinois to London flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Illinois to London?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Illinois to London.

  • Can I find deals for business class flights from Illinois to London?

    Yes. Cheapflights offers flight deals from Illinois to London by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

  • What is the cheapest month to book a flight from Illinois to London?

    Currently, September is the cheapest month in which you can book a flight from Illinois to London (average of $655). Flying from Illinois to London in February is currently the most expensive (average of $1,627). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

See more FAQs

Traveling to a place near London?

Book flights to London if you plan to visit one of these locations
Ilford
Dorking
Hounslow
Winchester
Croydon
Gatwick
Wembley
Harrow
Eastleigh
Dartford
Southend-on-Sea
Watford
Chipping Norton
Kingston upon Thames
Eastbourne
Slough
Stansted
Sutton
Luton
Harlow

Browse thousands of different options on Cheapflights for your next trip

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Top 10 airlines flying from Illinois to London

Discover the top 10 airlines that operate flights from Illinois to London. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated July 16, 2026.
AirlineCheapestAverageFlexibilityOn-time
JetBlueCheapest$51Average$81FlexibilityNo cancel feeOn-time62%
TAP AIR PORTUGALCheapest$428Average$713FlexibilityNo cancel feeOn-timeN/A
IcelandairCheapest$430Average$540FlexibilityNo cancel feeOn-time76%
Scandinavian AirlinesCheapest$456Average$600FlexibilityNo cancel feeOn-time77%
SWISSCheapest$458Average$786FlexibilityNo cancel feeOn-time79%
British AirwaysCheapest$513Average$838FlexibilityNo cancel feeOn-time70%
FinnairCheapest$516Average$831FlexibilityNo cancel feeOn-time76%
Alaska AirlinesCheapest$522Average$809FlexibilityNo cancel feeOn-time75%
IberiaCheapest$527Average$775FlexibilityNo cancel feeOn-time77%
United AirlinesCheapest$572Average$1,022FlexibilityNo cancel feeOn-time69%

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