Cheap flights from London Heathrow Airport to Illinois from £386
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 19/9. Fares are subject to change and may not be available on all flights or dates of travel.
Cheap flight deals from Heathrow to Illinois
Keep the following information in mind while searching for Heathrow to Illinois flight deals. Data was last updated 19 June 2025.
Find flight deals from Heathrow to Illinois
Cheapest flights from Heathrow to IllinoisExplore the most affordable flight options available from Heathrow to Illinois. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 19 June 2025.
Explore the most affordable flight options available from Heathrow to Illinois. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 19 June 2025.
Cheapflights Fare Finder
Customise your flight search to find flights from Heathrow 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 19 June 2025.
Use the filters below to find and compare flights from London Heathrow Airport to Illinois that are best for you.
Fly from
Fly to
Route
Depart
Return
Price
LondonChicago
LHR - ORD
LHRORD
London Heathrow
Thu 11/9
10:05-17:29
1 stop13h 24m
Chicago O'Hare Intl
Sat 20/9
18:52-12:45
1 stop11h 53m
LondonChicago
LHR - ORD
LHRORD
London Heathrow
Fri 29/8
08:30-23:25
2 stops20h 55m
Chicago O'Hare Intl
Thu 9/10
08:50-06:55
1 stop16h 05m
LondonChicago
LHR - MDW
LHRMDW
London Heathrow
Mon 8/9
08:40-18:37
2 stops15h 57m
Chicago Midway
Thu 18/9
09:30-08:55
1 stop17h 25m
LondonChicago
LHR - ORD
LHRORD
London Heathrow
Fri 5/9
09:30-18:12
2 stops14h 42m
Chicago O'Hare Intl
Sat 13/9
10:50-08:35
1 stop15h 45m
LondonChicago
LHR - ORD
LHRORD
London Heathrow
Tue 9/9
06:30-16:13
2 stops15h 43m
Chicago O'Hare Intl
Fri 19/9
18:10-11:25
1 stop11h 15m
LondonChicago
LHR - ORD
LHRORD
London Heathrow
Fri 22/8
08:00-16:10
1 stop14h 10m
Chicago O'Hare Intl
Mon 25/8
18:10-10:20
1 stop34h 10m
LondonChicago
LHR - ORD
LHRORD
London Heathrow
Sun 7/9
06:30-14:10
1 stop13h 40m
Chicago O'Hare Intl
Thu 18/9
13:16-06:45
1 stop11h 29m
LondonChicago
LHR - ORD
LHRORD
London Heathrow
Fri 5/9
06:50-12:05
1 stop11h 15m
Chicago O'Hare Intl
Mon 15/9
18:00-08:20
Nonstop8h 20m
LondonChicago
LHR - ORD
LHRORD
London Heathrow
Sat 23/8
20:05-12:10
1 stop22h 05m
Chicago O'Hare Intl
Sat 6/9
12:50-06:55
1 stop12h 05m
LondonChicago
LHR - MDW
LHRMDW
London Heathrow
Mon 24/11
06:20-18:07
2 stops17h 47m
Chicago Midway
Wed 3/12
13:00-06:55
2 stops11h 55m
Best time to book a flight from Heathrow to Illinois
Have a flexible travel schedule? Discover the best time to fly to Illinois from Heathrow with our price prediction graph.
Cheapflights Insights
Everything you need to know about your flight from London Heathrow Airport to Illinois
What is the cheapest month to book a flight from London Heathrow Airport to Illinois?
Currently, January is the cheapest month in which you can book a flight from London Heathrow Airport to Illinois (average of £595). Flying from London Heathrow Airport 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 LHR to IL?
Find hourly flight availability from Heathrow 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 19 June 2025.
When flying from London Heathrow Airport 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 Heathrow Airport to Illinois
Explore weekly flight availability from Heathrow 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 19 June 2025.
The most flights from LHR to USIL are scheduled on a Monday (53 on average). You will have fewer flight options on Thursday, which is when the least amount of flights are scheduled (47 on average).
Rainfall in Illinois by month
Plan your trip to Illinois by taking into account the average rainfall totals by month.
In terms of precipitation, rainfall in Illinois ranges from 43.0 - 125.0 inches per month. August is typically the wettest month, when rainfall can reach 125.0 mm. January is typically the driest time to visit Illinois when rainfall is around 43.0 mm.
Temperature in Illinois by month
Plan your trip to Illinois by taking into account the average temperature totals by month.
If weather is an important factor for your trip to Illinois, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 23.0 C. Travellers hoping to avoid the cold should look outside of January, when temperatures are typically at their lowest (around -5.0 C).
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 19 June 2025.
Read reviews from past customers who have flown Delta, KLM and Austrian Airlines from London to Illinois. You can also see how each airline compares in terms of entertainment options, comfort, food, crew/service, and boarding process.
Comfort
Crew
Food
Entertainment
Boarding
Overall
Reviews
Kim,May 2025
PIH - SLC
Comfort
Crew
Food
Entertainment
Boarding
Overall
Reviews
Kim,May 2025
PIH - SLC
Comfort
Crew
Food
Entertainment
Boarding
Overall
Reviews
Kim,May 2025
PIH - SLC
Comfort
Crew
Food
Entertainment
Boarding
Overall
Reviews
Kim,May 2025
PIH - SLC
Comfort
Crew
Food
Entertainment
Boarding
Overall
Reviews
Kim,May 2025
PIH - SLC
Comfort
Crew
Food
Entertainment
Boarding
Overall
Reviews
Kim,May 2025
PIH - SLC
Related info for your journey
Find useful and relevant information for your journey from Heathrow 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 Heathrow to Illinois
See prices for flight routes from nearby airports that may be better suited for you.
Top 10 airlines flying from Heathrow to Illinois
Discover the top 10 airlines that operate flights from Heathrow 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 19 June 2025.
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How does Cheapflights help users find flights from Heathrow to Illinois?
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Why should you use Cheapflights to find cheap flight tickets from Heathrow to Illinois?
Cheapflights taps into our reliable network of hundreds of airlines and travel agencies to find the best deals for flights from Heathrow to Illinois for you. Better yet — we are completely free to use.
Can Cheapflights find flights from Heathrow to Illinois with no change fees?
Yes! Cheapflights helps users easily find flights from Heathrow to Illinois with no change fees.
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