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Cheap flights from Illinois to London from £170

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 19/10. Fares are subject to change and may not be available on all flights or dates of travel.
ORD — LON
1 Sep — 8 Sep1
1 adult
1 adult, Economy, 0 bags

Cheap 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 2 August 2026.

Tue 10/1118:30
ORD
-
LGW
1 stop10h 25m
Icelandair
Wed 18/1111:55
LGW
-
ORD
1 stop11h 25m
Icelandair
Deal found 31/7£511
Sun 25/1020:15
ORD
-
LHR
2 stops55h 40m
Scandinavian Airlines
Thu 29/1007:05
LHR
-
ORD
2 stops15h 40m
Scandinavian Airlines
Deal found 30/7£512
Wed 23/919:25
ORD
-
LGW
2 stops15h 40m
Multiple Airlines
Wed 30/908:50
LGW
-
ORD
2 stops18h 35m
Multiple Airlines
Deal found 1/8£512
Wed 23/919:25
ORD
-
LHR
1 stop18h 55m
Icelandair
Wed 30/921:25
LHR
-
ORD
1 stop26h 50m
Icelandair
Deal found 1/8£512
Sat 24/1009:20
ORD
-
LGW
2 stops41h 55m
Multiple Airlines
Fri 30/1012:35
LGW
-
ORD
1 stop16h 15m
Multiple Airlines
Deal found 30/7£512
Mon 14/919:25
ORD
-
LGW
2 stops17h 00m
Multiple Airlines
Mon 21/918:05
LGW
-
ORD
2 stops30h 10m
Multiple Airlines
Deal found 31/7£513
Wed 14/1022:25
ORD
-
STN
2 stops16h 10m
Multiple Airlines
Wed 28/1016:40
STN
-
ORD
2 stops30h 05m
Multiple Airlines
Deal found 31/7£513
Sun 18/1019:25
ORD
-
LHR
1 stop10h 30m
Icelandair
Wed 28/1012:15
LHR
-
ORD
1 stop11h 05m
Icelandair
Deal found 30/7£514
Fri 16/1019:25
ORD
-
STN
2 stops19h 45m
Multiple Airlines
Sat 24/1005:55
STN
-
ORD
2 stops18h 20m
Multiple Airlines
Deal found 29/7£514
Sat 7/1119:15
ORD
-
LHR
1 stop17h 15m
Scandinavian Airlines
Sun 8/1121:05
LHR
-
ORD
2 stops25h 40m
Scandinavian Airlines
Deal found 1/8£515
Wed 21/1006:05
ORD
-
LGW
1 stop21h 55m
Multiple Airlines
Wed 28/1010:10
LGW
-
ORD
1 stop18h 40m
Multiple Airlines
Deal found 30/7£515
Fri 6/1121:48
ORD
-
LHR
2 stops41h 12m
Multiple Airlines
Mon 9/1118:00
LHR
-
ORD
2 stops26h 52m
Multiple Airlines
Deal found 31/7£515

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 2 August 2026.

Round-trip from

£511

One-way from

£170

Popular in

June

Cheapest in

February

Average price

£560

Good round-trip deal

£807 or less

Good one-way deal

£277 or less
Icelandair
  • Icelandair
  • 10/11-18/11
  • 2 total stops
  • 21h 50m total
  • Illinois to London
Search Deals
19/10
  • 19/10
  • 2 total stops
  • 41h 25m total
  • Illinois to London
Search Deals
Highest demand for flights based on searches. 26% potential increase in price (£160 potential increase over avg. return price).
Search Deals
Cheapest flight prices on average. 6% potential price decrease (£29 potential savings vs. average return price).
Search Deals
Average for round-trip flights in August 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

 
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 2 August 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 return flight

ChicagoLondon

ORD - LGW

ORDLGW

Chicago O'Hare Intl

Tue 8/9

17:29-10:00

1 stop34h 31m

London Gatwick

Mon 21/9

14:00-22:59

1 stop14h 59m

£525

ChicagoLondon

ORD - LTN

ORDLTN

Chicago O'Hare Intl

Wed 18/11

18:30-21:05

2 stops20h 35m

London Luton

Sun 29/11

21:45-17:20

2 stops25h 35m

£539

ChicagoLondon

ORD - LTN

ORDLTN

Chicago O'Hare Intl

Wed 16/9

19:25-22:15

2 stops20h 50m

London Luton

Wed 23/9

06:15-19:48

2 stops19h 33m

£558

ChicagoLondon

ORD - LGW

ORDLGW

Chicago O'Hare Intl

Fri 21/8

06:05-10:00

1 stop21h 55m

London Gatwick

Fri 4/9

14:00-23:08

1 stop15h 08m

£576

ChicagoLondon

ORD - LTN

ORDLTN

Chicago O'Hare Intl

Sun 13/9

17:35-22:20

2 stops22h 45m

London Luton

Thu 17/9

05:40-19:48

3 stops20h 08m

£581

ChicagoLondon

ORD - LHR

ORDLHR

Chicago O'Hare Intl

Thu 1/10

19:15-17:40

1 stop16h 25m

London Heathrow

Mon 5/10

07:05-16:10

2 stops15h 05m

£601

ChicagoLondon

ORD - LHR

ORDLHR

Chicago O'Hare Intl

Thu 26/11

19:15-18:30

1 stop17h 15m

London Heathrow

Mon 30/11

21:05-16:45

2 stops25h 40m

£604

ChicagoLondon

ORD - STN

ORDSTN

Chicago O'Hare Intl

Mon 17/8

20:10-09:55

1 stop31h 45m

London Stansted

Wed 30/9

10:50-09:40

1 stop28h 50m

£617

ChicagoLondon

ORD - STN

ORDSTN

Chicago O'Hare Intl

Wed 21/10

11:25-16:40

1 stop23h 15m

London Stansted

Thu 29/10

10:55-11:00

1 stop29h 05m

£617

ChicagoLondon

ORD - STN

ORDSTN

Chicago O'Hare Intl

Tue 22/9

11:25-16:50

1 stop23h 25m

London Stansted

Wed 30/9

17:45-09:40

1 stop21h 55m

£618

Flights are sorted by cheapest return flights first.

Deals found on 28/7

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 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, January is the cheapest month in which you can book a flight from Illinois to London (average of £483). Flying from Illinois to London in June is currently the most expensive (average of £1,024). 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 2 August 2026.

When flying from Illinois to London, the time of day you decide to fly out makes little to no difference towards the overall price you’ll pay on tickets.

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 2 August 2026.

The most flights from USIL to LON are scheduled on a Friday (57 on average). You will have fewer flight options on Wednesday, which is when the least amount of flights are scheduled (31 on average).

How much does it cost for a return flight from Illinois to London?

Airfare is typical for this route at the moment.
Illinois to London flights typically cost between £485 and £708 in November.
The cheapest return price found within the last 5 days was £511 on Icelandair (10 Nov–18 Nov).

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

Booking 74 days in advance of your planned departure date is, on average, the best time to get cheap flights from Illinois to London. The general trend is that the closer you book to the departure date, the more expensive your flight will be.

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 16h 25m. Illinois and London are separated by a distance of 3939 mi. This flight may include one or multiple stops.

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

    £164 is the cheapest one-way deal found within the past few days, from TAP AIR PORTUGAL. You may also be able to find cheap deals on Lufthansa and British Airways, with prices starting from £274 and £286, 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 Stansted 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: SriLankan Airlines (67%), Air Canada (67%), Austrian Airlines (67%).

  • What are the cheapest flights from Illinois to London?

    Looking for the cheapest flight from Illinois to London? While on average our users pay £638, our data indicates the cheapest price to be £274. The most popular route (Chicago O'Hare Intl - London Heathrow), is priced around £470.

  • 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, January is the cheapest month in which you can book a flight from Illinois to London (average of £483). Flying from Illinois to London in June is currently the most expensive (average of £1,024). 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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Romford

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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 2 August 2026.
AirlineCheapestAverageFlexibilityOn-time
IcelandairCheapest£363Average£552FlexibilityNo cancel feeOn-time76%
Search Icelandair flights
American AirlinesCheapest£384Average£820FlexibilityNo cancel feeOn-time71%
Search American Airlines flights
British AirwaysCheapest£411Average£606FlexibilityNo cancel feeOn-time70%
Search British Airways flights
Aer LingusCheapest£457Average£803FlexibilityNo cancel feeOn-timeN/A
Search Aer Lingus flights
United AirlinesCheapest£506Average£807FlexibilityNo cancel feeOn-time69%
Search United Airlines flights
IberiaCheapest£516Average£683FlexibilityNo cancel feeOn-time77%
Search Iberia flights
JetBlueCheapest£782Average£878FlexibilityNo cancel feeOn-time62%
Search JetBlue 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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