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Cheap flights from London to Illinois from £252

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 2/9. Fares are subject to change and may not be available on all flights or dates of travel.
LON — ORD
4 Sep — 11 Sep1
1 adult
1 adult, Economy, 0 bags

Cheap flight deals from London to Illinois

Enter your travel dates to find the best prices.

Cheapest flights from London to Illinois
Explore the most affordable flight options available from London to Illinois. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 5 August 2026.

Tue 22/916:25 -
1 stop29h 35m
Wed 21/1018:00 -
1 stop33h 45m
Deal found 5/8£481
Fri 4/906:35 -
1 stop13h 25m
Fri 11/921:00 -
1 stop18h 20m
Deal found 5/8£481
Thu 1/1019:50 -
1 stop26h 10m
Sun 11/1018:00 -
1 stop34h 20m
Deal found 5/8£481
Wed 7/1015:40 -
1 stop11h 45m
Wed 14/1022:25 -
1 stop10h 15m
Deal found 5/8£482
Tue 6/1021:25 -
1 stop26h 50m
Tue 13/1019:25 -
1 stop18h 55m
Deal found 4/8£483
Thu 3/913:00 -
1 stop12h 15m
Thu 10/921:00 -
1 stop20h 25m
Deal found 4/8£483
Sun 8/1120:35 -
1 stop26h 45m
Thu 12/1118:30 -
1 stop10h 20m
Deal found 4/8£483
Thu 17/913:00 -
1 stop12h 15m
Sun 27/921:00 -
1 stop12h 25m
Deal found 5/8£483
Mon 14/922:45 -
1 stop21h 15m
Tue 15/921:00 -
1 stop19h 20m
Deal found 5/8£483
Mon 7/908:40 -
1 stop11h 20m
Mon 21/921:00 -
1 stop17h 55m
Deal found 5/8£484
Wed 7/1013:05 -
1 stop14h 20m
Wed 14/1022:25 -
1 stop15h 55m
Deal found 5/8£484
Tue 1/909:15 -
2 stops18h 10m
Tue 8/919:25 -
2 stops19h 40m
Deal found 5/8£484

Find flight deals from London to Illinois

Keep the following information in mind while searching for London to Illinois flight deals. Data was last updated 5 August 2026.

Round-trip from

£481

One-way from

£252

Popular in

July

Cheapest in

February

Average price

£656

Good round-trip deal

£634 or less

Good one-way deal

£524 or less
TAP AIR PORTUGAL
  • TAP AIR PORTUGAL
  • 22/9-21/10
  • 2 total stops
  • 63h 20m total
  • London to Illinois
Search Deals
2/9
  • 2/9
  • 2 total stops
  • 33h 22m total
  • London to Illinois
Search Deals
Highest demand for flights based on searches. 16% potential increase in price (£82 potential increase over avg. return price).
Search Deals
Cheapest flight prices on average. 2% potential price decrease (£10 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 London (LON) to Illinois.
Search Deals
Price to beat on a one-way flight from London (LON) to Illinois.
Search Deals

Cheapflights Fare Finder

 
Customise your flight search to find flights from London to Illinois 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 5 August 2026.
Use the filters below to find and compare flights from London to Illinois that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest return flight

LondonChicago

LTN London Luton - ORD Chicago O'Hare Intl

LTNORD

London Luton

Tue 15/9

19:45-16:10

2 stops26h 25m

Chicago O'Hare Intl

Tue 22/9

19:15-19:05

2 stops17h 50m

£513

LondonChicago

LGW London Gatwick - MDW Chicago Midway

LGWMDW

London Gatwick

Fri 4/9

09:40-14:35

2 stops34h 55m

Chicago Midway

Mon 14/9

15:20-07:55

2 stops34h 35m

£519

LondonChicago

LTN London Luton - ORD Chicago O'Hare Intl

LTNORD

London Luton

Wed 28/10

21:45-18:20

2 stops25h 35m

Chicago O'Hare Intl

Wed 25/11

15:55-09:15

1 stop11h 20m

£524

LondonChicago

LTN London Luton - ORD Chicago O'Hare Intl

LTNORD

London Luton

Wed 2/9

06:15-14:00

1 stop13h 45m

Chicago O'Hare Intl

Tue 8/9

21:00-13:25

1 stop10h 25m

£549

LondonChicago

LHR London Heathrow - ORD Chicago O'Hare Intl

LHRORD

London Heathrow

Thu 1/10

21:05-16:10

2 stops25h 05m

Chicago O'Hare Intl

Sun 11/10

19:15-21:20

2 stops20h 05m

£550

LondonChicago

LHR London Heathrow - ORD Chicago O'Hare Intl

LHRORD

London Heathrow

Tue 15/9

21:05-16:10

2 stops25h 05m

Chicago O'Hare Intl

Tue 22/9

19:15-17:40

1 stop16h 25m

£563

LondonChicago

LGW London Gatwick - ORD Chicago O'Hare Intl

LGWORD

London Gatwick

Wed 9/9

15:40-21:25

1 stop11h 45m

Chicago O'Hare Intl

Wed 23/9

19:25-14:40

1 stop13h 15m

£566

LondonChicago

LHR London Heathrow - ORD Chicago O'Hare Intl

LHRORD

London Heathrow

Tue 6/10

07:05-16:10

2 stops15h 05m

Chicago O'Hare Intl

Tue 13/10

19:15-16:00

1 stop14h 45m

£570

LondonChicago

LHR London Heathrow - ORD Chicago O'Hare Intl

LHRORD

London Heathrow

Fri 18/9

06:40-16:10

2 stops15h 30m

Chicago O'Hare Intl

Mon 21/9

19:15-19:55

2 stops18h 40m

£573

LondonChicago

LGW London Gatwick - ORD Chicago O'Hare Intl

LGWORD

London Gatwick

Thu 15/10

15:40-18:15

1 stop32h 35m

Chicago O'Hare Intl

Tue 27/10

19:30-10:55

1 stop10h 25m

£574

Flights are sorted by cheapest return flights first.

Deals found on 1/8

Showing 1-10 of 60 resultsSorted by cheapest first
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6

Best time to book a flight from London to Illinois

Have a flexible travel schedule? Discover the best time to fly to Illinois from London 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 London to Illinois

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

Currently, February is the cheapest month in which you can book a flight from London to Illinois (average of £459). Flying from London to Illinois in July is currently the most expensive (average of £759). 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 LON to IL?

Find hourly flight availability from London to Illinois. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated 5 August 2026.

When flying from London to Illinois, 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 London to Illinois

Explore weekly flight availability from London to Illinois. 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 5 August 2026.

The most flights from LON to USIL are scheduled on a Monday (52 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (35 on average).

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

Airfare is below average for this route at the moment.
London to Illinois flights typically cost between £552 and £911 in September.
The cheapest return price found within the last 5 days was £481 on TAP AIR PORTUGAL (22 Sept–21 Oct).

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

The best time to book flights from London to Illinois is 79 days before your desired departure date. The cost of your flight will likely increase significantly if you book two weeks in advance of your flight.

Reviews of airlines servicing Illinois

Get insights into the airlines that provide service to Illinois. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Illinois. Reviews last updated 5 August 2026.
Read reviews from past customers who have flown with United Airlines,Aer Lingus, andIcelandair from London to Illinois. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
United Airlines
7.4
Good
10,066 reviews
Check prices

Comfort

7.3

Food

6.7

Overall

7.4

Boarding

7.7

Entertainment

7.1

Crew

8.1

Reviews

1 / 20
8.0
Excellent

Anonymous,Oct 2025

YUL - ORD

Crew and customer service are 5 stars. I had a lot of luggage for a very long trip and they were nothing but helpful and found solutions to every problem. It was my first time flying with United, and they really are the friendly skies. Leg room however, on 2/3 flights was terrible. Same for entertainment: There was only a seat-mounted screen on 1/3 flights. It would have been nice to have on the longest leg of the journey.
United Airlines
7.4
Good
10,066 reviews
United Airlines
7.4
Good
10,066 reviews
Check prices

Comfort

7.3

Food

6.7

Overall

7.4

Boarding

7.7

Entertainment

7.1

Crew

8.1

Reviews

1 / 20
8.0
Excellent

Anonymous,Oct 2025

YUL - ORD

Crew and customer service are 5 stars. I had a lot of luggage for a very long trip and they were nothing but helpful and found solutions to every problem. It was my first time flying with United, and they really are the friendly skies. Leg room however, on 2/3 flights was terrible. Same for entertainment: There was only a seat-mounted screen on 1/3 flights. It would have been nice to have on the longest leg of the journey.
Aer Lingus
7.3
Good
1,689 reviews
United Airlines
7.4
Good
10,066 reviews
Check prices

Comfort

7.3

Food

6.7

Overall

7.4

Boarding

7.7

Entertainment

7.1

Crew

8.1

Reviews

1 / 20
8.0
Excellent

Anonymous,Oct 2025

YUL - ORD

Crew and customer service are 5 stars. I had a lot of luggage for a very long trip and they were nothing but helpful and found solutions to every problem. It was my first time flying with United, and they really are the friendly skies. Leg room however, on 2/3 flights was terrible. Same for entertainment: There was only a seat-mounted screen on 1/3 flights. It would have been nice to have on the longest leg of the journey.
Icelandair
7.0
Good
721 reviews
United Airlines
7.4
Good
10,066 reviews
Check prices

Comfort

7.3

Food

6.7

Overall

7.4

Boarding

7.7

Entertainment

7.1

Crew

8.1

Reviews

1 / 20
8.0
Excellent

Anonymous,Oct 2025

YUL - ORD

Crew and customer service are 5 stars. I had a lot of luggage for a very long trip and they were nothing but helpful and found solutions to every problem. It was my first time flying with United, and they really are the friendly skies. Leg room however, on 2/3 flights was terrible. Same for entertainment: There was only a seat-mounted screen on 1/3 flights. It would have been nice to have on the longest leg of the journey.
Lufthansa
6.8
Okay
8,176 reviews
United Airlines
7.4
Good
10,066 reviews
Check prices

Comfort

7.3

Food

6.7

Overall

7.4

Boarding

7.7

Entertainment

7.1

Crew

8.1

Reviews

1 / 20
8.0
Excellent

Anonymous,Oct 2025

YUL - ORD

Crew and customer service are 5 stars. I had a lot of luggage for a very long trip and they were nothing but helpful and found solutions to every problem. It was my first time flying with United, and they really are the friendly skies. Leg room however, on 2/3 flights was terrible. Same for entertainment: There was only a seat-mounted screen on 1/3 flights. It would have been nice to have on the longest leg of the journey.
British Airways
6.7
Okay
8,147 reviews
United Airlines
7.4
Good
10,066 reviews
Check prices

Comfort

7.3

Food

6.7

Overall

7.4

Boarding

7.7

Entertainment

7.1

Crew

8.1

Reviews

1 / 20
8.0
Excellent

Anonymous,Oct 2025

YUL - ORD

Crew and customer service are 5 stars. I had a lot of luggage for a very long trip and they were nothing but helpful and found solutions to every problem. It was my first time flying with United, and they really are the friendly skies. Leg room however, on 2/3 flights was terrible. Same for entertainment: There was only a seat-mounted screen on 1/3 flights. It would have been nice to have on the longest leg of the journey.

Related info for your journey

Find useful and relevant information for your journey from London to Illinois. 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 London to Illinois?

    There are many flights that can get you from London to Illinois in 11h 45m. Fly via Scandinavian Airlines, Icelandair, or TAP AIR PORTUGAL to get the fastest option. Airlines will cover a distance of 3960 mi. When browsing for deals, the options you’ll see will be for both direct flights and flights with stops.

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

    For one-way options, check prices for JetBlue. According to our data, you can fly for as low as £310. Users have also found prices from £322 and £324 on Austrian Airlines and Icelandair, respectively.

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

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

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

    Before booking your flight to Illinois from London, check out the most reliable airlines to get you to your destination on time: Air Canada (90%), Austrian Airlines (90%), United Airlines( 90%).

  • What are the cheapest flights from London to Illinois?

    Looking for the cheapest flight from London to Illinois? While on average our users pay £2,828, our data indicates the cheapest price to be £402. The most popular route (London Heathrow - Chicago O'Hare Intl), is priced around £403.

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

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

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

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

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

    Yes. Cheapflights offers flight deals from London to Illinois 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 London to Illinois?

    Currently, February is the cheapest month in which you can book a flight from London to Illinois (average of £459). Flying from London to Illinois in July is currently the most expensive (average of £759). 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

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Alternative routes for London to Illinois

See prices for flight routes from nearby airports that may be better suited for you.
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Edinburgh to Newark flights
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Heathrow to Denver flights
Stansted to Dulles Intl flights
Gatwick to O'Hare Intl flights
Heathrow to Ontario flights
Luton to Los Angeles flights

Top 10 airlines flying from London to Illinois

Discover the top 10 airlines that operate flights from London to Illinois. 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 5 August 2026.
AirlineCheapestAverageFlexibilityOn-time
Virgin AtlanticCheapest£301Average£607FlexibilityNo cancel feeOn-time72%
Search Virgin Atlantic flights
IcelandairCheapest£348Average£492FlexibilityNo cancel feeOn-time76%
Search Icelandair flights
Aer LingusCheapest£363Average£674FlexibilityNo cancel feeOn-timeN/A
Search Aer Lingus flights
Scandinavian AirlinesCheapest£374Average£530FlexibilityNo cancel feeOn-time77%
Search Scandinavian Airlines flights
TAP AIR PORTUGALCheapest£386Average£573FlexibilityNo cancel feeOn-timeN/A
Search TAP AIR PORTUGAL flights
Brussels AirlinesCheapest£394Average£613FlexibilityNo cancel feeOn-timeN/A
Search Brussels Airlines flights
British AirwaysCheapest£410Average£666FlexibilityNo cancel feeOn-time70%
Search British Airways flights
LufthansaCheapest£413Average£645FlexibilityNo cancel feeOn-time76%
Search Lufthansa flights
FinnairCheapest£427Average£710FlexibilityNo cancel feeOn-time76%
Search Finnair flights
United AirlinesCheapest£428Average£705FlexibilityNo cancel feeOn-time69%
Search United Airlines 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 London to Illinois?

900+ travel sites are searched through when a user searches for a flight using Cheapflights. From the search interface, users can use filters to choose airlines, airports, flight times, cabin classes and more to their preference. Book your flight to Illinois from London today with Cheapflights!

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

Cheapflights simply makes it quick and affordable to book flights from London to Illinois by bringing together all flight options from hundreds of airlines and agencies online — and put it in one place for you to choose from. Plus, Cheapflights is 100% free to use for all.

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

Certainly. Search results for flights to Illinois from London 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 London to Illinois become cheaper?

Yes, Cheapflights has a feature called Price Alert, which notifies users when flight prices change. Track prices for your flight to Illinois from London today and book when prices fit your budget.

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