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Cheap flights from Illinois to London Heathrow Airport from £178

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 14/11. Fares are subject to change and may not be available on all flights or dates of travel.
ORD — LHR
14 Nov — 21 Nov1
1 adult
1 adult, Economy

Find flight deals from Illinois to Heathrow

Enter your travel dates to find the best prices.

Cheapest flights from Illinois to Heathrow
Explore the most affordable flight options available from Illinois to Heathrow. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 15 October 2025.

Tue 18/1118:30ORD - LHR
1 stop10h 20mIcelandair
Fri 5/1212:15LHR - ORD
1 stop11h 05mIcelandair
Deal found 12/10£394
Mon 29/1218:30ORD - LHR
1 stop10h 20mIcelandair
Fri 9/112:15LHR - ORD
1 stop11h 05mIcelandair
Deal found 13/10£395
Sun 16/1118:30ORD - LHR
1 stop10h 20mIcelandair
Wed 3/1220:35LHR - ORD
1 stop26h 45mIcelandair
Deal found 12/10£396
Wed 31/1218:30ORD - LHR
1 stop19h 00mIcelandair
Thu 15/112:15LHR - ORD
1 stop11h 05mIcelandair
Deal found 14/10£397
Sat 29/1119:20ORD - LHR
1 stop17h 10mScandinavian Airlines
Mon 1/1218:05LHR - ORD
2 stops52h 40mScandinavian Airlines
Deal found 13/10£397
Thu 13/1119:20ORD - LHR
1 stop32h 00mScandinavian Airlines
Sun 16/1106:40LHR - ORD
2 stops16h 05mScandinavian Airlines
Deal found 13/10£400
Sun 26/1015:50ORD - LHR
1 stop10h 15mVirgin Atlantic
Tue 4/1106:20LHR - ORD
1 stop14h 50mVirgin Atlantic
Deal found 13/10£402
Tue 4/1118:30ORD - LHR
1 stop10h 20mIcelandair
Fri 14/1112:15LHR - ORD
1 stop11h 05mIcelandair
Deal found 14/10£403
Fri 7/1119:20ORD - LHR
2 stops15h 05mScandinavian Airlines
Sun 9/1110:20LHR - ORD
1 stop12h 25mScandinavian Airlines
Deal found 14/10£405
Wed 31/1219:20ORD - LHR
1 stop16h 20mScandinavian Airlines
Thu 15/110:20LHR - ORD
1 stop12h 25mScandinavian Airlines
Deal found 13/10£409
Sun 26/1017:04MDW - LHR
1 stop10h 56mVirgin Atlantic
Tue 4/1111:05LHR - MDW
1 stop12h 38mVirgin Atlantic
Deal found 13/10£412
Tue 28/1006:00MDW - LHR
1 stop22h 00mVirgin Atlantic
Tue 4/1106:30LHR - MDW
2 stops15h 44mVirgin Atlantic
Deal found 13/10£418

Cheap flight deals from Illinois to Heathrow

Keep the following information in mind while searching for Illinois to Heathrow flight deals. Data was last updated 15 October 2025.

Round-trip from

£394

One-way from

£178

Popular in

June

Cheapest in

February

Average price

£503

Good round-trip deal

£427 or less

Good one-way deal

£296 or less
Icelandair
  • Icelandair
  • 18/11-5/12
  • 2 total stops
  • 21h 25m total
  • Illinois to London
Search Deals
TAP AIR PORTUGAL
  • TAP AIR PORTUGAL
  • 14/11
  • 1 total stop
  • 15h 15m total
  • Illinois to London
Search Deals
Highest demand for flights based on searches. 21% potential increase in price (£115 potential increase over avg. return price).
Search Deals
Cheapest flight prices on average. 4% potential price decrease (£21 potential savings vs. average return price).
Search Deals
Average for round-trip flights in October 2025
Search Deals
Price to beat on a round-trip flight from Illinois to London Heathrow.
Search Deals
Price to beat on a one-way flight from Illinois to London Heathrow.
Search Deals

Cheapflights Fare Finder

 
Customise your flight search to find flights from Illinois to Heathrow 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 15 October 2025.
Use the filters below to find and compare flights from Illinois to London Heathrow Airport that are best for you.

Fly from

Illinois

Fly to

Heathrow

Route

Depart

Return

Price

ChicagoLondon

ORD - LHR

ORDLHR

Chicago O'Hare Intl

Tue 3/2

07:00-09:20

2 stops20h 20m

London Heathrow

Tue 10/2

19:50-16:45

2 stops26h 55m

£409

ChicagoLondon

ORD - LHR

ORDLHR

Chicago O'Hare Intl

Mon 27/10

07:05-09:20

2 stops21h 15m

London Heathrow

Mon 3/11

07:05-16:45

2 stops15h 40m

£432

ChicagoLondon

ORD - LHR

ORDLHR

Chicago O'Hare Intl

Wed 3/12

19:10-11:25

1 stop10h 15m

London Heathrow

Wed 24/12

08:55-15:10

1 stop12h 15m

£434

ChicagoLondon

ORD - LHR

ORDLHR

Chicago O'Hare Intl

Mon 3/11

08:57-07:05

1 stop16h 08m

London Heathrow

Fri 14/11

09:00-15:10

1 stop12h 10m

£437

ChicagoLondon

ORD - LHR

ORDLHR

Chicago O'Hare Intl

Tue 25/11

17:10-06:55

Nonstop7h 45m

London Heathrow

Thu 12/2

11:00-13:50

Nonstop8h 50m

£440

ChicagoLondon

ORD - LHR

ORDLHR

Chicago O'Hare Intl

Sun 30/11

21:45-11:35

Nonstop7h 50m

London Heathrow

Fri 13/2

15:45-18:45

Nonstop9h 00m

£440

ChicagoLondon

ORD - LHR

ORDLHR

Chicago O'Hare Intl

Tue 4/11

11:23-07:50

1 stop14h 27m

London Heathrow

Tue 25/11

06:20-16:24

2 stops16h 04m

£445

ChicagoLondon

MDW - LHR

MDWLHR

Chicago Midway

Tue 11/11

10:47-07:50

1 stop15h 03m

London Heathrow

Tue 18/11

11:30-23:40

2 stops18h 10m

£445

ChicagoLondon

MDW - LHR

MDWLHR

Chicago Midway

Wed 3/12

09:59-07:05

1 stop15h 06m

London Heathrow

Wed 10/12

06:20-18:00

2 stops17h 40m

£445

ChicagoLondon

ORD - LHR

ORDLHR

Chicago O'Hare Intl

Tue 25/11

13:14-06:25

1 stop11h 11m

London Heathrow

Thu 4/12

08:40-19:55

2 stops17h 15m

£446

Flights are sorted by cheapest return flights first.

Deals found on 12/10

Showing 1-10 of 60 results
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Best time to book a flight from Illinois to Heathrow

Have a flexible travel schedule? Discover the best time to fly to Heathrow 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 Heathrow Airport

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

Currently, May is the cheapest month in which you can book a flight from Illinois to London Heathrow Airport (average of £294). Flying from Illinois to London Heathrow Airport in June is currently the most expensive (average of £676). 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 LHR?

Find hourly flight availability from Illinois to Heathrow. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated 15 October 2025.

It’s optimal to fly from Illinois to London Heathrow Airport in the afternoon. By choosing this option you can save up to 36% on the cost of your flight, compared to a flight at midday.

Weekly flight availability from Illinois to London Heathrow Airport

Explore weekly flight availability from Illinois to Heathrow. 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 15 October 2025.

The most flights from USIL to LHR are scheduled on a Monday (57 on average). You will have fewer flight options on Wednesday, which is when the least amount of flights are scheduled (51 on average).

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

Related info for your journey

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

    For as low as £434, Scandinavian Airlines can have you in London Heathrow Airport from Illinois in 10h 15m. The distance from Illinois to London Heathrow Airport is about 3939 mi. This flight may include one or multiple stops.

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

    The cheapest airline one-way is JetBlue, with whom users have recently found tickets for as low as £210. However, be on the lookout for offers from Virgin Atlantic and KLM, as they are both options that can get you from Illinois to London Heathrow Airport for a low price.

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

    The most popular route from Illinois to London Heathrow Airport is Chicago O'Hare Intl - London Heathrow. You may also consider Chicago Midway - London Heathrow or Lambert-St Louis - London Heathrow.

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

    No one likes to see their flight delayed. When booking a flight from Illinois to London Heathrow Airport consider choosing Royal Jordanian (76%), Aer Lingus (73%) or American Airlines (71%) as they are the most reliable in getting you off to your destination on time.

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

    On average you can expect to pay £400 for a flight from Illinois to London Heathrow Airport. The cheapest flight overall is £286 while the most popular route, (Chicago O'Hare Intl - London Heathrow) is currently priced at £322.

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

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

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

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

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

    Yes. Cheapflights offers flight deals from Illinois to Heathrow 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 Heathrow Airport?

    Currently, May is the cheapest month in which you can book a flight from Illinois to London Heathrow Airport (average of £294). Flying from Illinois to London Heathrow Airport in June is currently the most expensive (average of £676). 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 Heathrow Airport?

Book flights to London Heathrow Airport if you plan to visit one of these locations
Milton Keynes
Croydon
Slough
Gatwick
Hounslow
Northampton
Luton
Wembley
Deal
Ilford
Crawley
Hayes
Watford
Winchester
Swindon
Chichester
Romford
Ipswich
Brentford
Dartford

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Alternative routes for Illinois to Heathrow

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 Heathrow

Discover the top 7 airlines that operate flights from Illinois to Heathrow. 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 15 October 2025.
AirlineCheapestAverageFlexibilityOn-time
LufthansaCheapest£361Average£528FlexibilityNo cancel feeOn-time76%
Search Lufthansa flights
American AirlinesCheapest£389Average£634FlexibilityNo cancel feeOn-time71%
Search American Airlines flights
FinnairCheapest£418Average£680FlexibilityNo cancel feeOn-time76%
Search Finnair flights
IberiaCheapest£450Average£535FlexibilityNo cancel feeOn-time77%
Search Iberia flights
British AirwaysCheapest£454Average£568FlexibilityNo cancel feeOn-time70%
Search British Airways flights
United AirlinesCheapest£466Average£622FlexibilityNo cancel feeOn-time69%
Search United Airlines flights
Aer LingusCheapest£498Average£610FlexibilityNo cancel feeOn-timeN/A
Search Aer Lingus 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 Heathrow?

When you search for this flight from Illinois to Heathrow, Cheapflights searches on 900+ travel sites to save you time finding great flight deals online. Additionally, we offer filter features so you can choose a preferred cabin class or airline, see different price ranges, and much more so you can book the flight for you.

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

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 Heathrow from Illinois.

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

Cheapflights does show flights with no change fees to all users. To see these options for flights from Illinois to Heathrow, users can toggle the no change fees filter when performing a flight search.

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

Yes, Cheapflights offers price alerts on Illinois to Heathrow 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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