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Cheap flights from Illinois to London from £175

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 5/11. Fares are subject to change and may not be available on all flights or dates of travel.
ORD — LON
16 Nov — 23 Nov1
1 adult
1 adult, Economy

Find flight deals from Illinois to London

Enter your travel dates to find the best prices.

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 17 October 2025.

Tue 18/1118:30ORD - LHR
1 stop19h 00mIcelandair
Tue 2/1220:35LHR - ORD
1 stop26h 45mIcelandair
Deal found 16/10£392
Sat 6/1218:30ORD - STN
2 stops22h 35mMultiple Airlines
Sat 13/1206:30STN - ORD
2 stops16h 50mMultiple Airlines
Deal found 15/10£392
Wed 31/1218:30ORD - LHR
1 stop19h 00mIcelandair
Thu 15/112:15LHR - ORD
1 stop11h 05mIcelandair
Deal found 15/10£393
Mon 3/1119:20ORD - LHR
2 stops39h 40mScandinavian Airlines
Thu 6/1106:40LHR - ORD
1 stop16h 05mScandinavian Airlines
Deal found 16/10£394
Tue 11/1106:40ORD - LGW
1 stop17h 20mMultiple Airlines
Thu 13/1114:00LGW - ORD
1 stop28h 26mMultiple Airlines
Deal found 15/10£394
Sat 8/1118:30ORD - LGW
1 stop10h 25mIcelandair
Sat 15/1111:55LGW - ORD
1 stop11h 25mIcelandair
Deal found 16/10£395
Thu 27/1118:30ORD - LGW
2 stops22h 00mMultiple Airlines
Sat 6/1213:10LGW - ORD
3 stops34h 10mMultiple Airlines
Deal found 15/10£397
Mon 1/1218:30ORD - LTN
1 stop13h 30mMultiple Airlines
Mon 8/1208:00LTN - ORD
1 stop15h 20mMultiple Airlines
Deal found 17/10£398
Tue 11/1118:30ORD - LGW
1 stop10h 25mIcelandair
Mon 17/1111:55LGW - ORD
1 stop11h 25mIcelandair
Deal found 16/10£398
Fri 7/1119:20ORD - LHR
2 stops31h 35mScandinavian Airlines
Mon 10/1106:40LHR - ORD
1 stop16h 05mScandinavian Airlines
Deal found 16/10£398
Sun 30/1119:20ORD - STN
2 stops21h 15mMultiple Airlines
Thu 4/1211:30STN - ORD
2 stops35h 15mMultiple Airlines
Deal found 15/10£398
Wed 10/1207:05ORD - STN
2 stops28h 55mMultiple Airlines
Tue 16/1207:40STN - ORD
2 stops18h 30mMultiple Airlines
Deal found 15/10£399

Cheap flight deals from Illinois to London

Keep the following information in mind while searching for Illinois to London flight deals. Data was last updated 17 October 2025.

Round-trip from

£392

One-way from

£175

Popular in

June

Cheapest in

February

Average price

£498

Good round-trip deal

£423 or less

Good one-way deal

£293 or less
Icelandair
  • Icelandair
  • 18/11-2/12
  • 2 total stops
  • 45h 45m total
  • Illinois to London
Search Deals
5/11
  • 5/11
  • 2 total stops
  • 38h 08m total
  • Illinois to London
Search Deals
Highest demand for flights based on searches. 21% potential increase in price (£112 potential increase over avg. return price).
Search Deals
Cheapest flight prices on average. 5% potential price decrease (£20 potential savings vs. average return price).
Search Deals
Average for round-trip flights in October 2025
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

 
Customise 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 858,174 searches. Data last updated 17 October 2025.
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 - LHR

ORDLHR

Chicago O'Hare Intl

Thu 29/1

10:40-16:00

2 stops23h 20m

London Heathrow

Fri 6/2

06:40-16:45

1 stop16h 05m

£395

ChicagoLondon

ORD - LHR

ORDLHR

Chicago O'Hare Intl

Thu 26/2

10:40-09:20

2 stops16h 40m

London Heathrow

Mon 2/3

06:40-16:45

1 stop16h 05m

£395

ChicagoLondon

ORD - STN

ORDSTN

Chicago O'Hare Intl

Mon 24/11

15:50-09:50

1 stop12h 00m

London Stansted

Wed 3/12

08:30-17:55

1 stop15h 25m

£402

ChicagoLondon

ORD - LTN

ORDLTN

Chicago O'Hare Intl

Wed 12/11

15:50-08:35

1 stop10h 45m

London Luton

Wed 19/11

06:50-14:00

1 stop13h 10m

£404

ChicagoLondon

ORD - LHR

ORDLHR

Chicago O'Hare Intl

Tue 18/11

10:35-17:40

2 stops25h 05m

London Heathrow

Mon 24/11

07:05-16:45

2 stops15h 40m

£405

ChicagoLondon

ORD - LTN

ORDLTN

Chicago O'Hare Intl

Mon 24/11

15:50-08:35

1 stop10h 45m

London Luton

Wed 3/12

06:50-14:00

1 stop13h 10m

£407

ChicagoLondon

ORD - LHR

ORDLHR

Chicago O'Hare Intl

Thu 26/2

10:40-09:20

2 stops16h 40m

London Heathrow

Sun 1/3

21:05-16:45

2 stops25h 40m

£408

ChicagoLondon

ORD - STN

ORDSTN

Chicago O'Hare Intl

Wed 12/11

21:50-21:05

2 stops17h 15m

London Stansted

Thu 20/11

16:30-20:05

2 stops33h 35m

£409

ChicagoLondon

ORD - LTN

ORDLTN

Chicago O'Hare Intl

Sat 6/12

18:30-18:15

2 stops17h 45m

London Luton

Sat 13/12

06:00-17:20

2 stops17h 20m

£410

ChicagoLondon

ORD - LGW

ORDLGW

Chicago O'Hare Intl

Tue 13/1

18:30-10:55

1 stop10h 25m

London Gatwick

Thu 12/3

11:55-18:20

1 stop11h 25m

£426

Flights are sorted by cheapest return flights first.

Deals found on 16/10

Showing 1-10 of 60 results
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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 return 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 £291). Flying from Illinois to London in July is currently the most expensive (average of £456). 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 17 October 2025.

A simple way to save on the total cost of your ticket is to fly from Illinois to London in the afternoon. If you’re flexible enough to do this you can expect to save up to 38% on your trip compared to booking a flight at midday.

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 17 October 2025.

The most flights from USIL to LON are scheduled on a Monday (51 on average). You will have fewer flight options on Monday, which is when the least amount of flights are scheduled (51 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?

    Departing from Illinois to London will take you 10h 25m. Illinois and London are separated by a distance of 3960 mi. This flight may include one or multiple stops.

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

    £225 is the cheapest one-way deal found within the past few days, from JetBlue. You may also be able to find cheap deals on Scandinavian Airlines and SWISS, with prices starting from £255 and £310, respectively.

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

    When deciding which route to take from Illinois to London consider Chicago O'Hare Intl - London Heathrow, Chicago O'Hare Intl - London Gatwick or Chicago O'Hare Intl - London City as they are the most popular.

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

    Looking for the most reliable airlines to get you to your destination on time? Our data shows these are most likely to get you from Illinois to London on time: Royal Jordanian (80%), SriLankan Airlines (74%), Gulf Air (74%).

  • What are the cheapest flights from Illinois to London?

    Looking for the cheapest flight from Illinois to London? While on average our users pay £397, our data indicates the cheapest price to be £283. The most popular route (Chicago O'Hare Intl - London Heathrow), is priced around £327.

  • 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 holiday 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 £291). Flying from Illinois to London in July is currently the most expensive (average of £456). 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

Travelling to a place near London?

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Deal
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Guildford
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Alternative routes for Illinois to London

See prices for flight routes from nearby airports that may be better suited for you.
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Top 7 airlines flying from Illinois to London

Discover the top 7 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 858,174 searches. Data last updated 17 October 2025.
AirlineCheapestAverageFlexibilityOn-time
LufthansaCheapest£358Average£523FlexibilityNo cancel feeOn-time76%
Search Lufthansa flights
American AirlinesCheapest£385Average£629FlexibilityNo cancel feeOn-time71%
Search American Airlines flights
FinnairCheapest£414Average£673FlexibilityNo cancel feeOn-time76%
Search Finnair flights
IberiaCheapest£446Average£530FlexibilityNo cancel feeOn-time77%
Search Iberia flights
British AirwaysCheapest£450Average£563FlexibilityNo cancel feeOn-time70%
Search British Airways flights
United AirlinesCheapest£462Average£617FlexibilityNo cancel feeOn-time69%
Search United Airlines flights
Aer LingusCheapest£493Average£605FlexibilityNo cancel feeOn-timeN/A
Search Aer Lingus flights

Fly with Cheapflights

Find the best flight deals on Cheapflights, where travellers can enjoy low prices and a wide availability of flights to their desired destinations.

How does Cheapflights help users find flights from Illinois to London?

Cheapflights helps you search for flights from Illinois to London via 900+ travel sites so you don’t have to. After performing a flight search, users can also filter their flight selection by filtering for price, number of stops, airlines, and so on.

Why should you use Cheapflights to find cheap flight tickets from Illinois to London?

Cheapflights taps into our reliable network of hundreds of airlines and travel agencies to find the best deals for flights from Illinois to London for you. Better yet — we are completely free to use.

Can Cheapflights find flights from Illinois to London with no change fees?

Certainly. Search results for flights to London from Illinois shown to you on Cheapflights can be narrowed down with different useful search filters, which includes flexible booking options.

Can Cheapflights notify me if prices for flights from Illinois to London become cheaper?

Yes, Cheapflights offers price alerts on Illinois to London flights so you can book your travel at the perfect time. Price Alerts can be enabled by clicking the bell icon next to the flight deals above and providing your email address where you want to receive the alerts.

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