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Heathrow

$341+ 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 3/6. Fares are subject to change and may not be available on all flights or dates of travel.
ORD — LHR
Mar 14 — Mar 211
Sat 3/14
Sat 3/21
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 February 12, 2026.

This oojo deal was found by Cheapflights users on 2/8. 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 oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/307:25 pm
ORD
-
LHR
1 stop18h 55m
Icelandair
Tue 5/51:05 pm
LHR
-
ORD
1 stop11h 10m
Icelandair
Deal found 2/8$529
This oojo deal was found by Cheapflights users on 2/9. 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 oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/57:25 pm
ORD
-
LHR
1 stop18h 55m
Icelandair
Sun 5/109:25 pm
LHR
-
ORD
1 stop26h 50m
Icelandair
Deal found 2/9$531
This FlightHub deal was found by Cheapflights users on 2/9. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/177:15 pm
ORD
-
LHR
2 stops41h 15m
Scandinavian Airlines
Sun 9/205:00 pm
LHR
-
ORD
1 stop29h 10m
Scandinavian Airlines
Deal found 2/9$532
This FlightHub deal was found by Cheapflights users on 2/9. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/57:25 pm
ORD
-
LHR
1 stop10h 30m
Icelandair
Mon 5/111:05 pm
LHR
-
ORD
1 stop11h 10m
Icelandair
Deal found 2/9$533
This FlightHub deal was found by Cheapflights users on 2/9. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/57:25 pm
ORD
-
LHR
1 stop18h 55m
Icelandair
Tue 5/129:25 pm
LHR
-
ORD
1 stop26h 50m
Icelandair
Deal found 2/9$535
This Booking.com deal was found by Cheapflights users on 2/9. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/127:25 pm
ORD
-
LHR
1 stop10h 30m
Icelandair
Mon 5/189:25 pm
LHR
-
ORD
1 stop30h 00m
Icelandair
Deal found 2/9$536
This Kiwi.com deal was found by Cheapflights users on 2/10. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 4/207:25 pm
ORD
-
LHR
1 stop10h 30m
Icelandair
Thu 4/301:05 pm
LHR
-
ORD
1 stop11h 10m
Icelandair
Deal found 2/10$537
This Kiwi.com deal was found by Cheapflights users on 2/10. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 4/1910:25 pm
ORD
-
LHR
1 stop15h 55m
Icelandair
Thu 4/301:05 pm
LHR
-
ORD
1 stop11h 10m
Icelandair
Deal found 2/10$538
This Kiwi.com deal was found by Cheapflights users on 2/8. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/77:25 pm
ORD
-
LHR
1 stop10h 30m
Icelandair
Sat 4/119:25 pm
LHR
-
ORD
1 stop26h 50m
Icelandair
Deal found 2/8$539
This oojo deal was found by Cheapflights users on 2/11. 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 oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/237:25 pm
ORD
-
LHR
1 stop10h 30m
Icelandair
Tue 4/281:05 pm
LHR
-
ORD
1 stop11h 10m
Icelandair
Deal found 2/11$540
This oojo deal was found by Cheapflights users on 2/11. 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 oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/77:25 pm
ORD
-
LHR
1 stop10h 30m
Icelandair
Tue 4/219:25 pm
LHR
-
ORD
1 stop26h 50m
Icelandair
Deal found 2/11$541
This KAYAK deal was found by Cheapflights users on 2/10. 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 KAYAK is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 4/177:25 pm
ORD
-
LHR
1 stop18h 55m
Icelandair
Fri 4/249:25 pm
LHR
-
ORD
1 stop26h 50m
Icelandair
Deal found 2/10$542

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 February 12, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$529
(oojo)

One-way from

$341
(Kiwi.com)

Popular in

June

Cheapest in

September

Average price

$661

Good round-trip deal

$652 or less

Good one-way deal

$392 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. 21% potential increase in price ($207 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 5% potential price decrease ($36 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in February 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.
Search Deals

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 February 12, 2026.
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 3/3

5:50 pm-7:55 am

Nonstop8h 05m

London Heathrow

Tue 3/10

6:50 am-1:10 pm

1 stop11h 20m

$625

ChicagoLondon

ORD - LHR

ORDLHR

Chicago O'Hare Intl

Mon 2/23

2:12 pm-8:05 am

1 stop11h 53m

London Heathrow

Tue 3/3

8:40 am-6:01 pm

2 stops15h 21m

$640

ChicagoLondon

MDW - LHR

MDWLHR

Chicago Midway

Sun 3/1

9:34 am-8:45 am

1 stop17h 11m

London Heathrow

Tue 3/10

6:30 am-5:22 pm

2 stops15h 52m

$640

ChicagoLondon

ORD - LHR

ORDLHR

Chicago O'Hare Intl

Sun 3/29

4:25 pm-6:45 am

Nonstop8h 20m

London Heathrow

Wed 4/8

7:25 am-6:15 pm

1 stop16h 50m

$641

ChicagoLondon

ORD - LHR

ORDLHR

Chicago O'Hare Intl

Mon 3/23

6:45 pm-7:55 am

Nonstop8h 10m

London Heathrow

Tue 4/21

10:50 am-6:15 pm

1 stop13h 25m

$641

ChicagoLondon

ORD - LHR

ORDLHR

Chicago O'Hare Intl

Wed 4/29

6:00 am-6:45 am

1 stop18h 45m

London Heathrow

Thu 5/14

6:30 am-4:25 pm

2 stops15h 55m

$655

ChicagoLondon

ORD - LHR

ORDLHR

Chicago O'Hare Intl

Mon 4/6

7:00 pm-1:05 pm

1 stop12h 05m

London Heathrow

Wed 5/13

8:40 am-8:19 pm

2 stops17h 39m

$655

ChicagoLondon

MDW - LHR

MDWLHR

Chicago Midway

Wed 4/8

7:20 pm-1:05 pm

1 stop11h 45m

London Heathrow

Wed 4/22

8:40 am-6:36 pm

2 stops15h 56m

$655

ChicagoLondon

MDW - LHR

MDWLHR

Chicago Midway

Mon 4/13

1:23 pm-7:10 am

1 stop11h 47m

London Heathrow

Wed 4/22

8:40 am-6:36 pm

2 stops15h 56m

$655

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Sun 4/12

8:21 am-6:45 am

1 stop16h 24m

London Heathrow

Tue 4/21

10:50 am-9:08 pm

2 stops16h 18m

$657

Flights are sorted by cheapest round-trip flights first.

Deals found on 2/10

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 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, May is the cheapest month in which you can book a flight from Illinois to London Heathrow Airport (average of $391). Flying from Illinois to London Heathrow Airport in June is currently the most expensive (average of $889). 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 February 12, 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 February 12, 2026.

The most flights from USIL to LHR are scheduled on a Monday (45 on average). You will have fewer flight options on Thursday, which is when the least amount of flights are scheduled (19 on average).

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 $625, United Airlines can have you in London Heathrow Airport from Illinois in 8h 05m. There are 3939 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 $218 and $237 on Icelandair and TAP AIR PORTUGAL, 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 Aer Lingus (72%), American Airlines (67%) or Alaska Airlines (67%) 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 $2,634, our data shows the cheapest flight currently is $251. When looking at the most popular route, (Chicago O'Hare Intl - London Heathrow), you can expect to pay $436 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, May is the cheapest month in which you can book a flight from Illinois to London Heathrow Airport (average of $391). Flying from Illinois to London Heathrow Airport in June is currently the most expensive (average of $889). 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
Croydon
Hounslow
Southend-on-Sea
Harrow
Eastleigh
Gatwick
Dartford
Dover
Winchester
Orpington
Northampton
Watford
Hayes
Borehamwood
Broadway
Aylesbury
Chipping Norton
Horley
Kingston upon Thames

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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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Newark to Stansted flights
Newark to London City flights
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Boston to Stansted flights
Philadelphia to Heathrow flights
Dulles Intl to Stansted flights
O'Hare Intl to Gatwick flights
Newark to Luton flights
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Minneapolis to Heathrow flights
O'Hare Intl to London City flights
Tampa to Heathrow flights
Baltimore to Gatwick flights
O'Hare Intl to Stansted flights
San Francisco to Gatwick flights
Los Angeles to Stansted flights
Austin to Heathrow flights
Reagan-National to Gatwick flights
Dallas/Fort Worth to Gatwick flights
Los Angeles to London City flights
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San Francisco to Stansted flights
San Francisco to London City flights

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 February 12, 2026.
AirlineCheapestAverageFlexibilityOn-time
JetBlueCheapest$51Average$505FlexibilityNo cancel feeOn-time62%
SWISSCheapest$257Average$573FlexibilityNo cancel feeOn-time79%
Scandinavian AirlinesCheapest$331Average$559FlexibilityNo cancel feeOn-time77%
DeltaCheapest$345Average$732FlexibilityNo cancel feeOn-timeN/A
TAP AIR PORTUGALCheapest$428Average$586FlexibilityNo cancel feeOn-timeN/A
IcelandairCheapest$476Average$582FlexibilityNo cancel feeOn-time76%
LufthansaCheapest$480Average$1,131FlexibilityNo cancel feeOn-time76%
Aer LingusCheapest$492Average$763FlexibilityNo cancel feeOn-timeN/A
FinnairCheapest$516Average$775FlexibilityNo cancel feeOn-time76%
Alaska AirlinesCheapest$522Average$809FlexibilityNo cancel feeOn-time75%

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