HomeSearch by dateVacation packagesHotelsFlight dealsCar rentalTravel tips & news
London

$237+ 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 3/29. Fares are subject to change and may not be available on all flights or dates of travel.
ORD — LON
Mar 15 — Mar 221
Sun 3/15
Sun 3/22
1 adult, Economy
We work with more than 300 partners to bring you better travel deals

Find cheap flights from Illinois to London with Cheapflights

1. Tell us where you want to go

Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”

2. Select your favorite providers

We find the providers serving your travel needs. Choose up to four travel providers to compare side-by-side for flights, hotels, or car rentals.

3. Compare prices and book

Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.

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 February 13, 2026.

This oojo deal was found by Cheapflights users on 2/10. 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 oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 5/47:25 pm
ORD
-
LHR
1 stop10h 30m
Icelandair
Tue 5/129:25 pm
LHR
-
ORD
1 stop26h 50m
Icelandair
Deal found 2/10$531
This Mytrip deal was found by Cheapflights users on 2/11. 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.
Tue 3/36:30 pm
ORD
-
LTN
2 stops19h 35m
Multiple Airlines
Tue 3/109:00 am
LTN
-
ORD
2 stops14h 20m
Multiple Airlines
Deal found 2/11$535
This Mytrip deal was found by Cheapflights users on 2/10. 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 2/279:00 pm
ORD
-
LTN
1 stop13h 15m
Multiple Airlines
Sun 3/18:05 am
LTN
-
ORD
1 stop11h 55m
Multiple Airlines
Deal found 2/10$536
This FlightHub deal was found by Cheapflights users on 2/11. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/307:25 pm
ORD
-
LHR
1 stop18h 55m
Icelandair
Mon 5/49:25 pm
LHR
-
ORD
1 stop26h 50m
Icelandair
Deal found 2/11$536
This FlightHub deal was found by Cheapflights users on 2/11. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 5/1010:25 pm
ORD
-
LGW
1 stop31h 20m
Icelandair
Sat 5/163:40 pm
LGW
-
ORD
1 stop32h 35m
Icelandair
Deal found 2/11$536
This Kiwi.com deal was found by Cheapflights users on 2/10. 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 4/207:25 pm
ORD
-
LHR
1 stop10h 30m
Icelandair
Thu 4/301:05 pm
LHR
-
ORD
1 stop11h 10m
Icelandair
Deal found 2/10$537
This Kiwi.com deal was found by Cheapflights users on 2/10. 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.
Fri 4/1710:25 pm
ORD
-
LGW
1 stop10h 15m
Icelandair
Fri 4/243:40 pm
LGW
-
ORD
1 stop11h 45m
Icelandair
Deal found 2/10$537
This Kiwi.com deal was found by Cheapflights users on 2/10. 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 4/1910:25 pm
ORD
-
LHR
1 stop15h 55m
Icelandair
Thu 4/301:05 pm
LHR
-
ORD
1 stop11h 10m
Icelandair
Deal found 2/10$538
This KAYAK deal was found by Cheapflights users on 2/10. 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 KAYAK is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 4/187:25 pm
ORD
-
LGW
1 stop13h 15m
Icelandair
Fri 4/243:40 pm
LGW
-
ORD
1 stop11h 45m
Icelandair
Deal found 2/10$538
This Mytrip deal was found by Cheapflights users on 2/10. 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 2/279:00 pm
ORD
-
STN
1 stop13h 35m
Multiple Airlines
Sun 3/16:30 am
STN
-
ORD
1 stop13h 30m
Multiple Airlines
Deal found 2/10$538
This Kiwi.com deal was found by Cheapflights users on 2/10. 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.
Thu 4/167:25 pm
ORD
-
LHR
1 stop10h 30m
Icelandair
Mon 4/201:05 pm
LHR
-
ORD
1 stop11h 10m
Icelandair
Deal found 2/10$539
This Mytrip deal was found by Cheapflights users on 2/9. 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 4/157:25 pm
ORD
-
LGW
2 stops19h 15m
Multiple Airlines
Wed 4/228:50 am
LGW
-
ORD
2 stops15h 25m
Multiple Airlines
Deal found 2/9$539

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 February 13, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$531
(oojo)

One-way from

$237
(Kiwi.com)

Popular in

June

Cheapest in

September

Average price

$661

Good round-trip deal

$652 or less

Good one-way deal

$392 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. 21% potential increase in price ($207 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 5% potential price decrease ($36 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in February 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 February 13, 2026.
Use the filters below to find and compare flights from Illinois to London that are best for you.

Fly from

Illinois

Fly to

London

Route

Depart

Return

Price

ChicagoLondon

ORD - LTN

ORDLTN

Chicago O'Hare Intl

Tue 3/3

6:30 pm-8:05 pm

2 stops19h 35m

London Luton

Tue 3/10

9:00 am-6:20 pm

2 stops14h 20m

$535

ChicagoLondon

ORD - LTN

ORDLTN

Chicago O'Hare Intl

Thu 4/23

7:25 pm-11:25 pm

2 stops22h 00m

London Luton

Mon 4/27

8:15 am-6:15 pm

2 stops16h 00m

$556

ChicagoLondon

ORD - STN

ORDSTN

Chicago O'Hare Intl

Wed 2/25

6:30 pm-10:15 pm

2 stops21h 45m

London Stansted

Sat 2/28

5:20 pm-5:20 pm

2 stops30h 00m

$563

ChicagoLondon

ORD - LTN

ORDLTN

Chicago O'Hare Intl

Mon 4/20

7:15 pm-10:50 pm

2 stops21h 35m

London Luton

Sun 4/26

1:05 pm-4:10 pm

2 stops33h 05m

$574

ChicagoLondon

ORD - LTN

ORDLTN

Chicago O'Hare Intl

Mon 3/2

7:20 pm-10:30 pm

2 stops21h 10m

London Luton

Fri 3/6

8:50 pm-4:45 pm

2 stops25h 55m

$588

ChicagoLondon

ORD - LHR

ORDLHR

Chicago O'Hare Intl

Tue 3/3

9:15 pm-11:15 am

Nonstop8h 00m

London Heathrow

Wed 3/18

6:50 am-1:10 pm

1 stop11h 20m

$625

ChicagoLondon

ORD - LHR

ORDLHR

Chicago O'Hare Intl

Tue 2/24

5:50 pm-7:55 am

Nonstop8h 05m

London Heathrow

Tue 3/10

6:50 am-1:10 pm

1 stop11h 20m

$625

ChicagoLondon

ORD - LHR

ORDLHR

Chicago O'Hare Intl

Wed 3/11

4:45 pm-5:55 am

Nonstop8h 10m

London Heathrow

Wed 3/18

6:50 am-1:10 pm

1 stop11h 20m

$627

ChicagoLondon

ORD - LHR

ORDLHR

Chicago O'Hare Intl

Wed 3/11

4:45 pm-5:55 am

Nonstop8h 10m

London Heathrow

Mon 3/16

12:05 pm-5:20 pm

1 stop34h 15m

$628

ChicagoLondon

MDW - LHR

MDWLHR

Chicago Midway

Tue 3/3

1:29 pm-10:15 am

2 stops14h 46m

London Heathrow

Tue 3/10

6:30 am-5:22 pm

2 stops15h 52m

$645

Flights are sorted by cheapest round-trip flights first.

Deals found on 2/12

Showing 1-10 of 60 results
1
2
3
...
6

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, May is the cheapest month in which you can book a flight from Illinois to London (average of $391). Flying from Illinois to London in June is currently the most expensive (average of $889). 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 February 13, 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 February 13, 2026.

The most flights from USIL to LON are scheduled on a Tuesday (45 on average). You will have fewer flight options on Monday, which is when the least amount of flights are scheduled (41 on average).

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 $625, United Airlines can have you in London from Illinois in 8h. 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 $218 and $237 on Icelandair and TAP AIR PORTUGAL, 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 City, 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 Aer Lingus (72%), American Airlines (67%) or Alaska Airlines (67%) 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 $2,634 for a flight from Illinois to London. The cheapest flight overall is $251 while the most popular route, (Chicago O'Hare Intl - London Heathrow) is currently priced at $436.

  • 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, May is the cheapest month in which you can book a flight from Illinois to London (average of $391). Flying from Illinois to London in June is currently the most expensive (average of $889). 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
Croydon
Hounslow
Southend-on-Sea
Harrow
Eastleigh
Gatwick
Dartford
Dover
Winchester
Orpington
Watford
Hayes
Borehamwood
Aylesbury
Chipping Norton
Horley
Kingston upon Thames
Eastbourne
Sutton

Browse thousands of different options on Cheapflights for your next trip

Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.

Alternative routes for Illinois to London

See prices for flight routes from nearby airports that may be better suited for you.
John F Kennedy Intl to Heathrow flights
Newark to Heathrow flights
Boston to Heathrow flights
Dulles Intl to Heathrow flights
John F Kennedy Intl to Gatwick flights
LaGuardia to Heathrow flights
Los Angeles to Heathrow flights
John F Kennedy Intl to London City flights
Newark to Gatwick flights
O'Hare Intl to Heathrow flights
San Francisco to Heathrow flights
Dallas/Fort Worth to Heathrow flights
John F Kennedy Intl to Stansted flights
Baltimore to Heathrow flights
Seattle to Heathrow flights
LaGuardia to Gatwick flights
Boston to Gatwick flights
Hobby to Heathrow flights
Atlanta to Heathrow flights
Miami to Heathrow flights
Orlando to Heathrow flights
Reagan-National to Heathrow flights
John F Kennedy Intl to Luton flights
Dulles Intl to Gatwick flights
Boston to London City flights
Dulles Intl to London City flights
Denver to Heathrow flights
Dulles Intl to Stansted flights
Los Angeles to Gatwick flights
Newark to London City flights
Boston to Stansted flights
George Bush Intcntl to Heathrow flights
Newark to Stansted flights
Philadelphia to Heathrow flights
Newark to Luton flights
Baltimore to Gatwick flights
Minneapolis to Heathrow flights
O'Hare Intl to Gatwick flights
Newark to Edinburgh flights
Dallas/Fort Worth to Gatwick flights
John F Kennedy Intl to Edinburgh flights
Reagan-National to Gatwick flights
O'Hare Intl to London City flights
Tampa to Heathrow flights
San Francisco to Gatwick flights
Los Angeles to Stansted flights
O'Hare Intl to Stansted flights
Los Angeles to London City flights
Austin to Heathrow flights
Charlotte to Heathrow flights

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 February 13, 2026.
AirlineCheapestAverageFlexibilityOn-time
JetBlueCheapest$51Average$505FlexibilityNo cancel feeOn-time62%
SWISSCheapest$257Average$674FlexibilityNo cancel feeOn-time79%
Scandinavian AirlinesCheapest$331Average$559FlexibilityNo cancel feeOn-time77%
DeltaCheapest$345Average$897FlexibilityNo cancel feeOn-timeN/A
TAP AIR PORTUGALCheapest$428Average$586FlexibilityNo cancel feeOn-timeN/A
IcelandairCheapest$476Average$679FlexibilityNo cancel feeOn-time76%
LufthansaCheapest$480Average$1,131FlexibilityNo cancel feeOn-time76%
Aer LingusCheapest$492Average$763FlexibilityNo cancel feeOn-timeN/A
FinnairCheapest$516Average$775FlexibilityNo cancel feeOn-time76%
Alaska AirlinesCheapest$522Average$809FlexibilityNo cancel feeOn-time75%

100% Free

Cheapflights is completely free to use, so you can start saving the moment you arrive.

Book with Flexibility

Our users can plan ahead with confidence and find flights with no change fees

Travel Smart

Millions of people come to us for their flight needs every year. We help make travel planning easy by providing useful insights and data-driven graphs that can inform your decisions.