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Cheap flights from the United Kingdom to Illinois from £309
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 1/10. Fares are subject to change and may not be available on all flights or dates of travel.
LHR — ORD
16 Oct — 23 Oct1
Cheap flight deals from United Kingdom to Illinois
Keep the following information in mind while searching for United Kingdom to Illinois flight deals. Data was last updated 16 September 2025.
Find flight deals from United Kingdom to Illinois
Cheapest flights from United Kingdom to IllinoisExplore the most affordable flight options available from United Kingdom to Illinois. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 16 September 2025.
Explore the most affordable flight options available from United Kingdom to Illinois. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 16 September 2025.
Wed 1/1009:50LHR - ORD
1 stop11h 55mBritish Airways
Mon 6/1017:40ORD - LHR
Nonstop7h 40mBritish Airways
Deal found 15/9£394
Wed 15/1015:30LGW - ORD
2 stops27h 05mMultiple Airlines
Wed 22/1006:40ORD - LGW
1 stop17h 40mMultiple Airlines
Deal found 15/9£394
Fri 3/1007:40LHR - ORD
1 stop14h 05mAmerican Airlines
Fri 10/1013:43ORD - LHR
1 stop10h 37mAmerican Airlines
Deal found 14/9£394
Mon 22/914:00LGW - ORD
1 stop32h 12mMultiple Airlines
Sun 5/1006:00ORD - LGW
1 stop22h 10mMultiple Airlines
Deal found 15/9£395
Fri 19/906:50LHR - ORD
1 stop11h 15mMultiple Airlines
Mon 22/921:50ORD - LHR
Nonstop7h 55mMultiple Airlines
Deal found 12/9£395
Fri 3/1013:05LGW - ORD
2 stops34h 34mMultiple Airlines
Tue 7/1011:13ORD - LGW
1 stop13h 07mMultiple Airlines
Deal found 14/9£396
Mon 8/1219:50LHR - ORD
2 stops50h 55mScandinavian Airlines
Sat 10/119:20ORD - LHR
1 stop14h 40mScandinavian Airlines
Deal found 14/9£396
Sat 27/914:00LGW - ORD
1 stop34h 50mMultiple Airlines
Sat 11/1018:58ORD - LGW
1 stop33h 12mMultiple Airlines
Deal found 12/9£397
Thu 9/1007:45LHR - ORD
2 stops14h 50mUnited Airlines
Tue 14/1014:39ORD - LHR
1 stop10h 16mUnited Airlines
Deal found 15/9£397
Wed 1/1012:20LGW - ORD
2 stops16h 52mAmerican Airlines
Mon 6/1013:43ORD - LGW
1 stop12h 27mAmerican Airlines
Deal found 15/9£397
Thu 6/1112:35LHR - ORD
Nonstop8h 50mBritish Airways
Wed 12/1121:45ORD - LHR
Nonstop7h 50mBritish Airways
Deal found 13/9£397
Sun 14/1212:15LHR - ORD
1 stop11h 05mIcelandair
Thu 15/118:30ORD - LHR
1 stop19h 00mIcelandair
Deal found 15/9£398
Cheapflights Fare Finder
Customise your flight search to find flights from United Kingdom 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 16 September 2025.
Use the filters below to find and compare flights from the United Kingdom to Illinois that are best for you.
Fly from
United Kingdom
Fly to
Illinois
Route
Depart
Return
Price
LondonChicago
LHR - ORD
LHRORD
London Heathrow
Tue 9/12
07:05-16:45
2 stops39h 40m
Chicago O'Hare Intl
Fri 9/1
19:20-16:00
1 stop14h 40m
£396
LondonChicago
LHR - ORD
LHRORD
London Heathrow
Wed 1/10
07:45-16:35
2 stops14h 50m
Chicago O'Hare Intl
Sun 12/10
14:08-09:35
1 stop13h 27m
£397
LondonChicago
LHR - ORD
LHRORD
London Heathrow
Mon 15/12
12:15-17:20
1 stop11h 05m
Chicago O'Hare Intl
Thu 15/1
18:30-19:30
1 stop19h 00m
£398
LondonChicago
LHR - ORD
LHRORD
London Heathrow
Tue 9/12
12:15-17:20
1 stop11h 05m
Chicago O'Hare Intl
Wed 7/1
18:30-10:50
1 stop10h 20m
£398
LondonChicago
LHR - ORD
LHRORD
London Heathrow
Sat 13/12
20:35-17:20
1 stop26h 45m
Chicago O'Hare Intl
Thu 8/1
18:30-19:30
1 stop19h 00m
£400
LondonChicago
LGW - ORD
LGWORD
London Gatwick
Thu 9/10
14:00-18:46
1 stop34h 46m
Chicago O'Hare Intl
Thu 23/10
18:58-10:00
1 stop33h 02m
£400
LondonChicago
LGW - ORD
LGWORD
London Gatwick
Tue 7/10
14:00-17:53
1 stop33h 53m
Chicago O'Hare Intl
Fri 5/12
06:05-10:00
1 stop21h 55m
£400
LondonChicago
LHR - ORD
LHRORD
London Heathrow
Fri 26/9
06:50-12:05
1 stop11h 15m
Chicago O'Hare Intl
Sun 28/9
21:25-11:45
Nonstop8h 20m
£403
LondonChicago
LHR - ORD
LHRORD
London Heathrow
Thu 30/10
07:05-18:45
2 stops16h 40m
Chicago O'Hare Intl
Sun 2/11
19:20-16:25
2 stops15h 05m
£404
LondonChicago
LTN - ORD
LTNORD
London Luton
Wed 15/10
10:00-19:00
1 stop15h 00m
Chicago O'Hare Intl
Wed 22/10
21:15-20:45
1 stop17h 30m
£407
Showing 1-10 of 60 results
Best time to book a flight from United Kingdom to Illinois
Have a flexible travel schedule? Discover the best time to fly to Illinois from United Kingdom 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 the United Kingdom to Illinois
What is the cheapest month to book a flight from United Kingdom to Illinois?
Currently, January is the cheapest month in which you can book a flight from United Kingdom to Illinois (average of £595). Flying from United Kingdom to Illinois in July is currently the most expensive (average of £843). 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 GB to IL?
Find hourly flight availability from United Kingdom 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 16 September 2025.
When flying from United Kingdom 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 United Kingdom to Illinois
Explore weekly flight availability from United Kingdom 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 16 September 2025.
The most flights from GB0 to USIL are scheduled on a Sunday (54 on average). You will have fewer flight options on Thursday, which is when the least amount of flights are scheduled (42 on average).
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 16 September 2025.
Read through reviews of airlines operating flights from the United Kingdom to Illinois, such as Finnair, Aer Lingus, andIcelandair. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.
Crew
8.1
Overall
7.6
Boarding
7.6
Entertainment
6.9
Comfort
7.5
Food
6.7
Reviews
1 / 20
10.0
ExcellentAnonymous,May 2025
FRA - DFW
Crew
8.1
Overall
7.6
Boarding
7.6
Entertainment
6.9
Comfort
7.5
Food
6.7
Reviews
1 / 20
10.0
ExcellentAnonymous,May 2025
FRA - DFW
Crew
8.1
Overall
7.6
Boarding
7.6
Entertainment
6.9
Comfort
7.5
Food
6.7
Reviews
1 / 20
10.0
ExcellentAnonymous,May 2025
FRA - DFW
Crew
8.1
Overall
7.6
Boarding
7.6
Entertainment
6.9
Comfort
7.5
Food
6.7
Reviews
1 / 20
10.0
ExcellentAnonymous,May 2025
FRA - DFW
Crew
8.1
Overall
7.6
Boarding
7.6
Entertainment
6.9
Comfort
7.5
Food
6.7
Reviews
1 / 20
10.0
ExcellentAnonymous,May 2025
FRA - DFW
Crew
8.1
Overall
7.6
Boarding
7.6
Entertainment
6.9
Comfort
7.5
Food
6.7
Reviews
1 / 20
10.0
ExcellentAnonymous,May 2025
FRA - DFW
Related info for your journey
Find useful and relevant information for your journey from United Kingdom to Illinois. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.
Browse thousands of different options on Cheapflights for your next trip
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Alternative routes for United Kingdom to Illinois
See prices for flight routes from nearby airports that may be better suited for you.
Top 10 airlines flying from United Kingdom to Illinois
Discover the top 10 airlines that operate flights from United Kingdom 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 16 September 2025.
Fly with Cheapflights
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How does Cheapflights help users find flights from United Kingdom 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 United Kingdom today with Cheapflights!
Why should you use Cheapflights to find cheap flight tickets from United Kingdom to Illinois?
By finding flights from multiple airlines and providers at completely no cost, Cheapflights helps millions of users like you annually find the best flights to Illinois from United Kingdom.
Can Cheapflights find flights from United Kingdom to Illinois with no change fees?
Cheapflights does show flights with no change fees to all users. To see these options for flights from United Kingdom to Illinois, users can toggle the no change fees filter when performing a flight search.
Can Cheapflights notify me if prices for flights from United Kingdom to Illinois become cheaper?
Yes, Cheapflights offers price alerts on United Kingdom to Illinois 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.