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Cheap flights from London Heathrow Airport to Illinois from £377

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 2/11. Fares are subject to change and may not be available on all flights or dates of travel.
LHR — ORD
31 Aug — 7 Sep1
1 adult

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 26 August 2025.

Round-trip from

£422

One-way from

£377

Popular in

July

Cheapest in

February

Average price

£623

Good round-trip deal

£495 or less

Good one-way deal

£554 or less
Austrian Airlines
  • Austrian Airlines
  • 9/10-16/10
  • 1 total stop
  • 21h 40m total
  • London to Illinois
Search Deals
2/11
  • 2/11
  • 3 total stops
  • 58h 02m total
  • London to Illinois
Search Deals
Highest demand for flights based on searches. 13% potential increase in price (£61 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 2025
Search Deals
Price to beat on a round-trip flight from London Heathrow to Illinois.
Search Deals
Price to beat on a one-way flight from London Heathrow to Illinois.
Search Deals

Find flight deals from Heathrow to Illinois

Cheapest flights from Heathrow to Illinois
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 26 August 2025.

Sat 13/909:05LHR - ORD
1 stop34h 15mUnited Airlines
Sun 5/1021:25ORD - LHR
Nonstop8h 20mUnited Airlines
Deal found 25/8£422
Mon 1/907:25LHR - ORD
1 stop12h 40mUnited Airlines
Tue 30/911:45ORD - LHR
1 stop12h 10mUnited Airlines
Deal found 25/8£422
Wed 3/907:40LHR - ORD
1 stop14h 05mAmerican Airlines
Sat 13/920:40ORD - LHR
Nonstop7h 50mAmerican Airlines
Deal found 24/8£423
Sun 21/908:30LHR - ORD
1 stop12h 25mLufthansa
Thu 16/1018:00ORD - LHR
Nonstop8h 20mLufthansa
Deal found 24/8£424
Mon 1/908:30LHR - ORD
1 stop12h 25mUnited Airlines
Sun 14/921:50ORD - LHR
Nonstop7h 55mUnited Airlines
Deal found 25/8£425
Sun 14/906:50LHR - ORD
1 stop11h 15mUnited Airlines
Fri 3/1008:40ORD - LHR
1 stop15h 50mUnited Airlines
Deal found 25/8£425
Sun 31/806:50LHR - ORD
1 stop11h 05mUnited Airlines
Sat 13/910:43ORD - LHR
1 stop14h 12mUnited Airlines
Deal found 24/8£426
Mon 1/907:25LHR - ORD
1 stop12h 40mUnited Airlines
Thu 2/1014:00ORD - LHR
1 stop15h 50mUnited Airlines
Deal found 25/8£427
Tue 9/906:50LHR - ORD
2 stops14h 14mAir Canada
Tue 16/914:08ORD - LHR
1 stop13h 27mAir Canada
Deal found 24/8£428
Mon 1/907:25LHR - ORD
1 stop12h 40mUnited Airlines
Fri 3/1022:30ORD - LHR
1 stop13h 10mUnited Airlines
Deal found 25/8£428
Sun 31/806:00LHR - ORD
1 stop12h 10mMultiple Airlines
Sat 13/912:50ORD - LHR
1 stop12h 05mMultiple Airlines
Deal found 24/8£429
Sun 19/1010:20LHR - ORD
1 stop11h 50mScandinavian Airlines
Thu 6/1119:20ORD - LHR
2 stops15h 05mScandinavian Airlines
Deal found 24/8£430

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 26 August 2025.
Use the filters below to find and compare flights from London Heathrow Airport to Illinois that are best for you.

Fly from

Heathrow

Fly to

Illinois

Route

Depart

Return

Price

LondonChicago

LHR - ORD

LHRORD

London Heathrow

Wed 26/11

07:40-14:10

1 stop12h 30m

Chicago O'Hare Intl

Fri 16/1

15:45-05:55

Nonstop8h 10m

£422

LondonChicago

LHR - ORD

LHRORD

London Heathrow

Thu 27/11

07:40-14:10

1 stop12h 30m

Chicago O'Hare Intl

Sat 17/1

13:00-06:40

1 stop11h 40m

£422

LondonChicago

LHR - ORD

LHRORD

London Heathrow

Wed 26/11

07:40-14:10

1 stop12h 30m

Chicago O'Hare Intl

Sat 17/1

17:50-07:55

Nonstop8h 05m

£422

LondonChicago

LHR - ORD

LHRORD

London Heathrow

Wed 26/11

07:40-14:10

1 stop12h 30m

Chicago O'Hare Intl

Fri 16/1

13:00-06:40

1 stop11h 40m

£422

LondonChicago

LHR - ORD

LHRORD

London Heathrow

Sun 5/10

07:30-14:55

1 stop13h 25m

Chicago O'Hare Intl

Sun 12/10

16:00-06:20

Nonstop8h 20m

£424

LondonChicago

LHR - ORD

LHRORD

London Heathrow

Sun 21/9

08:30-14:55

1 stop12h 25m

Chicago O'Hare Intl

Thu 16/10

14:39-06:55

1 stop10h 16m

£424

LondonChicago

LHR - ORD

LHRORD

London Heathrow

Sun 21/9

08:30-14:55

1 stop12h 25m

Chicago O'Hare Intl

Thu 16/10

18:00-08:20

Nonstop8h 20m

£424

LondonChicago

LHR - ORD

LHRORD

London Heathrow

Sun 21/9

08:30-14:55

1 stop12h 25m

Chicago O'Hare Intl

Sun 28/9

16:00-06:20

Nonstop8h 20m

£424

LondonChicago

LHR - ORD

LHRORD

London Heathrow

Thu 25/9

08:30-14:55

1 stop12h 25m

Chicago O'Hare Intl

Mon 29/9

18:00-08:20

Nonstop8h 20m

£424

LondonChicago

LHR - ORD

LHRORD

London Heathrow

Thu 9/10

07:30-14:55

1 stop13h 25m

Chicago O'Hare Intl

Thu 16/10

13:17-06:45

1 stop11h 28m

£424

Flights are sorted by cheapest return flights first.

Deals found on 25/8

Showing 1-10 of 60 results
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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.
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 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 26 August 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 26 August 2025.

The most flights from LHR to USIL are scheduled on a Saturday (54 on average). You will have fewer flight options on Thursday, which is when the least amount of flights are scheduled (47 on average).

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

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 26 August 2025.
Read through reviews of airlines operating flights from London Heathrow Airport 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.
Finnair
7.6
Good
1,320 reviews
Check prices

Food

6.7

Overall

7.6

Comfort

7.5

Entertainment

6.9

Crew

8.1

Boarding

7.6

Reviews

1 / 20
10.0
Excellent

Anonymous,May 2025

FRA - DFW

I was lucky I had a seet without no one next to me My vegetarian meal was excellent. The service very good. Although there was a lot of turbulences during the flight, the landing was very soft and took away all our apprehension.
Finnair
7.6
Good
1,320 reviews
Finnair
7.6
Good
1,320 reviews
Check prices

Food

6.7

Overall

7.6

Comfort

7.5

Entertainment

6.9

Crew

8.1

Boarding

7.6

Reviews

1 / 20
10.0
Excellent

Anonymous,May 2025

FRA - DFW

I was lucky I had a seet without no one next to me My vegetarian meal was excellent. The service very good. Although there was a lot of turbulences during the flight, the landing was very soft and took away all our apprehension.
Aer Lingus
7.2
Good
1,237 reviews
Finnair
7.6
Good
1,320 reviews
Check prices

Food

6.7

Overall

7.6

Comfort

7.5

Entertainment

6.9

Crew

8.1

Boarding

7.6

Reviews

1 / 20
10.0
Excellent

Anonymous,May 2025

FRA - DFW

I was lucky I had a seet without no one next to me My vegetarian meal was excellent. The service very good. Although there was a lot of turbulences during the flight, the landing was very soft and took away all our apprehension.
Icelandair
7.0
Good
533 reviews
Finnair
7.6
Good
1,320 reviews
Check prices

Food

6.7

Overall

7.6

Comfort

7.5

Entertainment

6.9

Crew

8.1

Boarding

7.6

Reviews

1 / 20
10.0
Excellent

Anonymous,May 2025

FRA - DFW

I was lucky I had a seet without no one next to me My vegetarian meal was excellent. The service very good. Although there was a lot of turbulences during the flight, the landing was very soft and took away all our apprehension.
Lufthansa
6.8
Okay
7,359 reviews
Finnair
7.6
Good
1,320 reviews
Check prices

Food

6.7

Overall

7.6

Comfort

7.5

Entertainment

6.9

Crew

8.1

Boarding

7.6

Reviews

1 / 20
10.0
Excellent

Anonymous,May 2025

FRA - DFW

I was lucky I had a seet without no one next to me My vegetarian meal was excellent. The service very good. Although there was a lot of turbulences during the flight, the landing was very soft and took away all our apprehension.
British Airways
6.7
Okay
7,309 reviews
Finnair
7.6
Good
1,320 reviews
Check prices

Food

6.7

Overall

7.6

Comfort

7.5

Entertainment

6.9

Crew

8.1

Boarding

7.6

Reviews

1 / 20
10.0
Excellent

Anonymous,May 2025

FRA - DFW

I was lucky I had a seet without no one next to me My vegetarian meal was excellent. The service very good. Although there was a lot of turbulences during the flight, the landing was very soft and took away all our apprehension.

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.

  • How long is the flight from London Heathrow Airport to Illinois?

    Departing from London Heathrow Airport to Illinois will take you 12h 30m. The distance from London Heathrow Airport to Illinois is about 3939 mi. Both multi-stop and direct flights can be found to your destination and back.

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

    One-way options have recently been found by users for as low as £411 on TAP AIR PORTUGAL. Other airlines that offer cheap prices include Scandinavian Airlines from £411 and Aer Lingus from £412 one-way.

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

    The most popular flight routes from London Heathrow Airport to Illinois are London Heathrow - Chicago O'Hare Intl, London Heathrow - Chicago Midway and London Heathrow - Lambert-St Louis.

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

    Before booking your flight to Illinois from London Heathrow Airport, check out the most reliable airlines to get you to your destination on time: Air Canada (73%), Austrian Airlines (73%), United Airlines( 73%).

  • What are the cheapest flights from London Heathrow Airport to Illinois?

    Looking at all options, your cheapest flight can be booked for £418. While the most popular route (London Heathrow - Chicago O'Hare Intl) can be booked for £328 on average our data indicates £1,443 when flying from London Heathrow Airport to Illinois.

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

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

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

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

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

    Yes. Cheapflights offers flight deals from Heathrow 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 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.

See more FAQs

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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.
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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 26 August 2025.
AirlineCheapestAverageFlexibilityOn-time
IcelandairCheapest£342Average£454FlexibilityNo cancel feeOn-time76%
Search Icelandair flights
Scandinavian AirlinesCheapest£352Average£478FlexibilityNo cancel feeOn-time77%
Search Scandinavian Airlines flights
TAP AIR PORTUGALCheapest£367Average£612FlexibilityNo cancel feeOn-timeN/A
Search TAP AIR PORTUGAL flights
Aer LingusCheapest£372Average£572FlexibilityNo cancel feeOn-timeN/A
Search Aer Lingus flights
Virgin AtlanticCheapest£379Average£552FlexibilityNo cancel feeOn-time72%
Search Virgin Atlantic flights
Brussels AirlinesCheapest£392Average£576FlexibilityNo cancel feeOn-timeN/A
Search Brussels Airlines flights
LufthansaCheapest£396Average£577FlexibilityNo cancel feeOn-time76%
Search Lufthansa flights
Austrian AirlinesCheapest£402Average£581FlexibilityNo cancel feeOn-time78%
Search Austrian Airlines flights
British AirwaysCheapest£406Average£559FlexibilityNo cancel feeOn-time70%
Search British Airways flights
United AirlinesCheapest£407Average£680FlexibilityNo 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 Heathrow to Illinois?

Cheapflights helps you search for flights from Heathrow to Illinois 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 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.

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

Of course! You can now track prices for flights from Heathrow to Illinois and get an alert from Cheapflights when they change. Have a valid email address ready and click the bell icon next to the flight deals above to set up your price alerts.

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