HomeSearch by dateVacation packagesHotelsFlight dealsCar rentalTravel tips & news
London

$329+ 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 9/23. Fares are subject to change and may not be available on all flights or dates of travel.
ORD — LON
May 25 — Jun 11
Mon 5/25
Mon 6/1
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 April 25, 2026.

This Mytrip deal was found by Cheapflights users on 4/20. 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 5/127:25 pm
ORD
-
STN
2 stops19h 05m
Multiple Airlines
Tue 5/193:10 pm
STN
-
ORD
2 stops30h 50m
Multiple Airlines
Deal found 4/20$695
This Kiwi.com deal was found by Cheapflights users on 4/20. 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 9/304:30 pm
ORD
-
LGW
1 stop31h 50m
Multiple Airlines
Tue 10/61:05 pm
LGW
-
ORD
1 stop24h 56m
Multiple Airlines
Deal found 4/20$699
This Mytrip deal was found by Cheapflights users on 4/21. 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 5/127:25 pm
ORD
-
LGW
2 stops21h 25m
Multiple Airlines
Tue 5/199:35 pm
LGW
-
ORD
3 stops28h 05m
Multiple Airlines
Deal found 4/21$701
This Mytrip deal was found by Cheapflights users on 4/20. 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.
Sun 5/310:25 pm
ORD
-
LGW
3 stops28h 15m
Multiple Airlines
Wed 5/278:50 pm
LGW
-
ORD
3 stops28h 50m
Multiple Airlines
Deal found 4/20$702
This Mytrip deal was found by Cheapflights users on 4/21. 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 5/269:55 am
ORD
-
STN
3 stops27h 40m
Multiple Airlines
Wed 6/310:00 pm
STN
-
ORD
2 stops27h 25m
Multiple Airlines
Deal found 4/21$702
This Gotogate deal was found by Cheapflights users on 4/20. 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 Gotogate is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/307:25 pm
ORD
-
LGW
1 stop13h 15m
Icelandair
Wed 10/73:40 pm
LGW
-
ORD
1 stop11h 45m
Icelandair
Deal found 4/20$705
This Gotogate deal was found by Cheapflights users on 4/20. 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 Gotogate is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 11/286:30 pm
ORD
-
LGW
1 stop10h 25m
Icelandair
Sat 12/1211:55 am
LGW
-
ORD
1 stop11h 25m
Icelandair
Deal found 4/20$706
This Gotogate deal was found by Cheapflights users on 4/20. 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 Gotogate is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 11/286:30 pm
ORD
-
LHR
1 stop10h 20m
Icelandair
Sat 12/1212:15 pm
LHR
-
ORD
1 stop11h 05m
Icelandair
Deal found 4/20$707
This Gotogate deal was found by Cheapflights users on 4/20. 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 Gotogate is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 12/126:30 pm
ORD
-
LGW
1 stop10h 25m
Icelandair
Fri 12/2511:55 am
LGW
-
ORD
1 stop11h 25m
Icelandair
Deal found 4/20$708
This Gotogate deal was found by Cheapflights users on 4/20. 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 Gotogate is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 12/126:30 pm
ORD
-
LHR
1 stop10h 20m
Icelandair
Fri 12/2512:15 pm
LHR
-
ORD
1 stop11h 05m
Icelandair
Deal found 4/20$709
This Mytrip deal was found by Cheapflights users on 4/20. 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 11/33:55 pm
ORD
-
STN
2 stops20h 30m
Multiple Airlines
Tue 11/176:30 am
STN
-
ORD
2 stops16h 50m
Multiple Airlines
Deal found 4/20$709
This Gotogate deal was found by Cheapflights users on 4/20. 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 Gotogate is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 11/26:30 pm
ORD
-
LGW
1 stop10h 25m
Icelandair
Mon 11/911:55 am
LGW
-
ORD
1 stop11h 25m
Icelandair
Deal found 4/20$710

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 April 25, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$695
(Mytrip)

One-way from

$335
(Delta)

Popular in

June

Cheapest in

February

Average price

$699

Good round-trip deal

$941 or less

Good one-way deal

$508 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. 22% potential increase in price ($228 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 5% potential price decrease ($39 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in April 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 April 25, 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

Tue 6/2

8:50 am-1:25 pm

3 stops22h 35m

London Luton

Tue 6/9

3:15 pm-6:15 pm

2 stops33h 00m

$811

ChicagoLondon

ORD - LTN

ORDLTN

Chicago O'Hare Intl

Tue 9/8

4:05 pm-12:55 pm

2 stops14h 50m

London Luton

Fri 9/18

8:30 am-6:15 pm

2 stops15h 45m

$823

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Wed 9/9

1:30 pm-1:15 pm

1 stop17h 45m

London Heathrow

Tue 9/15

6:30 am-4:55 pm

2 stops16h 25m

$868

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Tue 10/13

4:13 pm-12:05 pm

1 stop13h 52m

London Heathrow

Tue 10/20

6:30 am-4:50 pm

2 stops16h 20m

$868

ChicagoLondon

MDW - LGW

MDWLGW

Chicago Midway

Sun 5/10

10:30 am-10:45 am

1 stop18h 15m

London Gatwick

Tue 5/19

8:50 am-9:45 am

2 stops30h 55m

$870

ChicagoLondon

ORD - LGW

ORDLGW

Chicago O'Hare Intl

Wed 10/21

5:10 pm-9:25 am

1 stop10h 15m

London Gatwick

Tue 10/27

10:00 am-4:10 pm

1 stop11h 10m

$871

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Tue 9/8

1:30 pm-10:20 am

2 stops14h 50m

London Heathrow

Tue 9/29

6:30 am-4:55 pm

2 stops16h 25m

$872

ChicagoLondon

MDW - LHR

MDWLHR

Chicago Midway

Mon 8/17

1:05 pm-6:25 am

1 stop11h 20m

London Heathrow

Fri 8/28

8:40 am-6:05 pm

2 stops15h 25m

$874

ChicagoLondon

MDW - LGW

MDWLGW

Chicago Midway

Wed 5/20

3:20 pm-10:45 am

1 stop13h 25m

London Gatwick

Wed 5/27

2:00 pm-10:02 pm

2 stops38h 02m

$875

ChicagoLondon

ORD - LCY

ORDLCY

Chicago O'Hare Intl

Tue 5/5

4:20 pm-9:30 am

1 stop11h 10m

London City

Tue 5/19

9:20 am-2:15 pm

1 stop10h 55m

$889

Flights are sorted by cheapest round-trip flights first.

Deals found on 4/23

Showing 1-10 of 60 resultsSorted by cheapest first
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

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.

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

Currently, November is the cheapest month in which you can book a flight from Illinois to London (average of $639). Flying from Illinois to London in February is currently the most expensive (average of $1,203). 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 April 25, 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 April 25, 2026.

The most flights from USIL to LON are scheduled on a Friday (58 on average). You will have fewer flight options on Wednesday, which is when the least amount of flights are scheduled (53 on average).

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

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 $890, Delta can have you in London from Illinois in 8h 15m. 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 $219 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 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 Air Canada (89%), Austrian Airlines (89%) or United Airlines (89%) 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 $2,349 for a flight from Illinois to London. The cheapest flight overall is $339 while the most popular route, (Chicago O'Hare Intl - London Heathrow) is currently priced at $608.

  • 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, November is the cheapest month in which you can book a flight from Illinois to London (average of $639). Flying from Illinois to London in February is currently the most expensive (average of $1,203). 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
Hounslow
Winchester
Croydon
Gatwick
Southend-on-Sea
Harrow
Eastleigh
Dartford
Dover
Orpington
Watford
Borehamwood
Chipping Norton
Hayes
Kingston upon Thames
Eastbourne
Slough
Sutton
Stansted

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.

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 April 25, 2026.
AirlineCheapestAverageFlexibilityOn-time
JetBlueCheapest$51Average$373FlexibilityNo cancel feeOn-time62%
Scandinavian AirlinesCheapest$321Average$579FlexibilityNo cancel feeOn-time77%
DeltaCheapest$345Average$877FlexibilityNo cancel feeOn-timeN/A
SWISSCheapest$377Average$728FlexibilityNo cancel feeOn-time79%
TAP AIR PORTUGALCheapest$428Average$645FlexibilityNo cancel feeOn-timeN/A
IcelandairCheapest$465Average$665FlexibilityNo cancel feeOn-time76%
Aer LingusCheapest$481Average$829FlexibilityNo cancel feeOn-timeN/A
FinnairCheapest$513Average$830FlexibilityNo cancel feeOn-time76%
Alaska AirlinesCheapest$522Average$677FlexibilityNo cancel feeOn-time75%
British AirwaysCheapest$532Average$822FlexibilityNo cancel feeOn-time70%

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.