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Heathrow

$314+ Cheap flights from Illinois to Heathrow (LHR)

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 8/4. Fares are subject to change and may not be available on all flights or dates of travel.
ORD — LHR
Jul 24 — Jul 311
Fri 7/24
Fri 7/31
1 adult, Economy
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Cheap flight deals from Illinois to Heathrow

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 June 24, 2026.

This Virgin Atlantic deal was found by Cheapflights users on 6/23. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Virgin Atlantic is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 11/3011:00 am
MLI
-
LHR
1 stop18h 40m
Virgin Atlantic
Tue 12/86:30 am
LHR
-
MLI
2 stops22h 00m
Virgin Atlantic
Deal found 6/23$437
This United Airlines deal was found by Cheapflights users on 6/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/1010:35 am
MLI
-
LHR
1 stop15h 20m
United Airlines
Thu 11/126:50 am
LHR
-
MLI
2 stops14h 17m
United Airlines
Deal found 6/22$736
This United Airlines deal was found by Cheapflights users on 6/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/277:14 pm
PIA
-
LHR
1 stop31h 41m
United Airlines
Fri 10/306:50 am
LHR
-
PIA
2 stops20h 58m
United Airlines
Deal found 6/22$736
This The Travel House deal was found by Cheapflights users on 6/21. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure The Travel House is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 7/175:43 pm
PIA
-
LHR
1 stop32h 47m
Lufthansa
Tue 8/256:50 am
LHR
-
PIA
2 stops18h 13m
Lufthansa
Deal found 6/21$819
This United Airlines deal was found by Cheapflights users on 6/21. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/43:44 pm
MLI
-
LHR
1 stop33h 01m
United Airlines
Sun 9/136:50 am
LHR
-
MLI
2 stops33h 17m
United Airlines
Deal found 6/21$864
This United Airlines deal was found by Cheapflights users on 6/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 8/233:35 pm
PIA
-
LHR
1 stop14h 20m
United Airlines
Tue 9/156:50 am
LHR
-
PIA
2 stops20h 09m
United Airlines
Deal found 6/22$864
This United Airlines deal was found by Cheapflights users on 6/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/125:45 am
PIA
-
LHR
1 stop20h 45m
United Airlines
Wed 8/197:25 am
LHR
-
PIA
2 stops17h 38m
United Airlines
Deal found 6/22$865
This United Airlines deal was found by Cheapflights users on 6/21. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 9/61:15 pm
MLI
-
LHR
2 stops14h 45m
United Airlines
Sun 9/136:50 am
LHR
-
MLI
2 stops18h 41m
United Airlines
Deal found 6/21$867
This United Airlines deal was found by Cheapflights users on 6/23. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/238:13 am
MLI
-
LHR
2 stops16h 42m
United Airlines
Wed 9/306:50 am
LHR
-
MLI
2 stops18h 13m
United Airlines
Deal found 6/23$868
This United Airlines deal was found by Cheapflights users on 6/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/198:13 am
MLI
-
LHR
2 stops15h 42m
United Airlines
Fri 8/287:25 am
LHR
-
MLI
2 stops16h 20m
United Airlines
Deal found 6/22$869
This United Airlines deal was found by Cheapflights users on 6/21. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/146:39 pm
PIA
-
LHR
2 stops15h 01m
United Airlines
Sat 9/196:50 am
LHR
-
PIA
2 stops14h 07m
United Airlines
Deal found 6/21$872
This United Airlines deal was found by Cheapflights users on 6/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/28:32 am
PIA
-
LHR
1 stop18h 28m
United Airlines
Thu 10/84:25 pm
LHR
-
PIA
2 stops32h 36m
United Airlines
Deal found 6/22$875

Find flight deals from Illinois to Heathrow

Keep the following information in mind while searching for Illinois to Heathrow flight deals. Data was last updated June 24, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$437
(Virgin Atlantic)

One-way from

$314
(Mytrip)

Popular in

June

Cheapest in

September

Average price

$1,375

Good round-trip deal

$1,080 or less

Good one-way deal

$467 or less
Provider with most accurate pricing for Chicago (CHI)-London (LON) flight deals.
Search Deals
Provider most trusted by Cheapflights users for Chicago (CHI)-London (LON) flights.
Search Deals
From Illinois to London Heathrow
Search Deals
One-way flight from Illinois to London Heathrow
Search Deals
Highest demand for flights based on searches. 26% potential increase in price ($283 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 7% potential price decrease ($53 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in June 2026
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.
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Cheapflights Fare Finder

 
Customize 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 2,558,603 searches. Data last updated June 24, 2026.
Use the filters below to find and compare flights from Illinois to London Heathrow Airport that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

MolineLondon

MLI - LHR

MLILHR

Moline Quad-City

Mon 11/30

5:55 am-9:00 am

1 stop21h 05m

London Heathrow

Tue 12/8

8:55 am-10:30 pm

1 stop19h 35m

$451

MolineLondon

MLI - LHR

MLILHR

Moline Quad-City

Tue 11/10

10:35 am-7:55 am

1 stop15h 20m

London Heathrow

Thu 11/12

6:50 am-3:07 pm

2 stops14h 17m

$736

MolineLondon

MLI - LHR

MLILHR

Moline Quad-City

Wed 9/23

8:13 am-11:55 am

1 stop21h 42m

London Heathrow

Wed 9/30

6:50 am-10:38 pm

2 stops21h 48m

$864

MolineLondon

MLI - LHR

MLILHR

Moline Quad-City

Fri 9/4

3:44 pm-6:45 am

1 stop33h 01m

London Heathrow

Sun 9/13

6:50 am-10:07 am

2 stops33h 17m

$864

PeoriaLondon

PIA - LHR

PIALHR

Greater Peoria

Sun 8/23

3:35 pm-11:55 am

1 stop14h 20m

London Heathrow

Tue 9/15

6:50 am-8:59 pm

2 stops20h 09m

$864

PeoriaLondon

PIA - LHR

PIALHR

Greater Peoria

Wed 8/12

8:29 am-6:30 am

2 stops16h 01m

London Heathrow

Wed 8/19

7:25 am-7:03 pm

2 stops17h 38m

$868

MolineLondon

MLI - LHR

MLILHR

Moline Quad-City

Wed 8/19

8:13 am-5:55 am

2 stops15h 42m

London Heathrow

Fri 8/28

7:25 am-5:45 pm

2 stops16h 20m

$869

EvansvilleLondon

EVV - LHR

EVVLHR

Evansville Dress Regional

Tue 10/20

10:05 am-6:25 am

1 stop14h 20m

London Heathrow

Fri 10/30

11:45 am-9:25 am

2 stops26h 40m

$876

PeoriaLondon

PIA - LHR

PIALHR

Greater Peoria

Sun 8/23

8:29 am-6:45 am

1 stop16h 16m

London Heathrow

Tue 9/15

1:30 pm-10:59 pm

2 stops15h 29m

$924

BloomingtonLondon

BMI - LHR

BMILHR

Bloomington-Normal

Sun 8/23

12:09 pm-6:25 am

1 stop12h 16m

London Heathrow

Tue 9/15

6:30 am-10:34 pm

2 stops22h 04m

$934

Flights are sorted by cheapest round-trip flights first.

Deals found on 6/21

Showing 1-10 of 60 resultsSorted by cheapest first
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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 round-trip 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, October is the cheapest month in which you can book a flight from Illinois to London Heathrow Airport (average of $110). Flying from Illinois to London Heathrow Airport in September is currently the most expensive (average of $1,865). 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 June 24, 2026.

Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Illinois to London Heathrow Airport as you normally would.

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 June 24, 2026.

The most flights from USIL to LHR are scheduled on a Tuesday (56 on average). You will have fewer flight options on Wednesday, which is when the least amount of flights are scheduled (46 on average).

How much does it cost to fly round-trip from Illinois to London Heathrow Airport?

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

The best time to book flights from Illinois to London Heathrow Airport is 42 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.

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 $940, United Airlines can have you in London Heathrow Airport from Illinois in 11h 43m. There are 3942 mi between Illinois and London Heathrow Airport. This flight may include one or multiple stops.

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

    For one-way options, check prices for JetBlue. According to our data, you can fly for as low as $135. Users have also found prices from $219 and $279 on Icelandair and Finnair, respectively.

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

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

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

    Consider Air Canada (72%), Austrian Airlines (72%) or United Airlines (72%) when booking your flight. These represent the most reliable airlines when flying from Illinois to London Heathrow Airport.

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

    While on average a flight from Illinois to London Heathrow Airport is generally $2,325, our data shows the cheapest flight currently is $328. When looking at the most popular route, (Chicago O'Hare Intl - London Heathrow), you can expect to pay $617 for that flight.

  • 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 vacation 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, October is the cheapest month in which you can book a flight from Illinois to London Heathrow Airport (average of $110). Flying from Illinois to London Heathrow Airport in September is currently the most expensive (average of $1,865). 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

Traveling to a place near London Heathrow Airport?

Book flights to London Heathrow Airport if you plan to visit one of these locations
Ilford
Dorking
Hounslow
Winchester
Croydon
Gatwick
Southend-on-Sea
Wembley
Harrow
Eastleigh
Dartford
Dover
Orpington
Watford
Northampton
Chipping Norton
Hayes
Kingston upon Thames
Eastbourne
Slough

Browse thousands of different options on Cheapflights for your next trip

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Top 10 airlines flying from Illinois to Heathrow

Discover the top 10 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 2,558,603 searches. Data last updated June 24, 2026.
AirlineCheapestAverageFlexibilityOn-time
JetBlueCheapest$51Average$81FlexibilityNo cancel feeOn-time62%
Scandinavian AirlinesCheapest$384Average$593FlexibilityNo cancel feeOn-time77%
TAP AIR PORTUGALCheapest$428Average$696FlexibilityNo cancel feeOn-timeN/A
IcelandairCheapest$481Average$538FlexibilityNo cancel feeOn-time76%
FinnairCheapest$513Average$817FlexibilityNo cancel feeOn-time76%
British AirwaysCheapest$513Average$816FlexibilityNo cancel feeOn-time70%
IberiaCheapest$516Average$749FlexibilityNo cancel feeOn-time77%
Alaska AirlinesCheapest$522Average$809FlexibilityNo cancel feeOn-time75%
SWISSCheapest$562Average$823FlexibilityNo cancel feeOn-time79%
United AirlinesCheapest$573Average$1,017FlexibilityNo cancel feeOn-time69%

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