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$367+ 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 7/12. Fares are subject to change and may not be available on all flights or dates of travel.
ORD — LHR
Apr 22 — Apr 291
Wed 4/22
Wed 4/29
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 March 23, 2026.

This Gotogate deal was found by Cheapflights users on 3/20. 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 Gotogate is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 4/256:05 pm
ORD
-
LHR
1 stop34h 15m
TAP AIR PORTUGAL
Sat 5/96:00 am
LHR
-
ORD
1 stop16h 05m
TAP AIR PORTUGAL
Deal found 3/20$621
This FlightHub deal was found by Cheapflights users on 3/18. 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.
Wed 12/27:20 pm
ORD
-
LHR
2 stops20h 00m
Scandinavian Airlines
Wed 12/910:20 am
LHR
-
ORD
1 stop12h 35m
Scandinavian Airlines
Deal found 3/18$623
This FlightHub deal was found by Cheapflights users on 3/18. 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.
Fri 10/97:15 pm
ORD
-
LHR
2 stops15h 10m
Scandinavian Airlines
Sun 10/187:50 pm
LHR
-
ORD
2 stops26h 20m
Scandinavian Airlines
Deal found 3/18$624
This FlightHub deal was found by Cheapflights users on 3/23. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/26:05 pm
ORD
-
LHR
1 stop12h 40m
TAP AIR PORTUGAL
Tue 5/196:45 pm
LHR
-
ORD
1 stop27h 15m
TAP AIR PORTUGAL
Deal found 3/23$632
This Booking.com deal was found by Cheapflights users on 3/20. 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.
Sun 5/36:00 pm
ORD
-
LHR
1 stop34h 20m
TAP AIR PORTUGAL
Fri 5/156:45 pm
LHR
-
ORD
1 stop27h 20m
TAP AIR PORTUGAL
Deal found 3/20$633
This FlightHub deal was found by Cheapflights users on 3/18. 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.
Sat 11/287:20 pm
ORD
-
LHR
2 stops35h 35m
Scandinavian Airlines
Tue 12/110:20 am
LHR
-
ORD
1 stop12h 25m
Scandinavian Airlines
Deal found 3/18$635
This Booking.com deal was found by Cheapflights users on 3/22. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 4/176:00 pm
ORD
-
LHR
1 stop12h 45m
TAP AIR PORTUGAL
Tue 4/216:45 pm
LHR
-
ORD
1 stop27h 15m
TAP AIR PORTUGAL
Deal found 3/22$638
This CrystalTravel deal was found by Cheapflights users on 3/18. 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 CrystalTravel is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 11/97:20 pm
ORD
-
LHR
1 stop14h 40m
Scandinavian Airlines
Thu 11/1910:20 am
LHR
-
ORD
1 stop12h 25m
Scandinavian Airlines
Deal found 3/18$640
This oojo deal was found by Cheapflights users on 3/21. 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 oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/26:05 pm
ORD
-
LHR
1 stop15h 30m
TAP AIR PORTUGAL
Fri 5/87:50 pm
LHR
-
ORD
1 stop26h 15m
TAP AIR PORTUGAL
Deal found 3/21$641
This Gotogate deal was found by Cheapflights users on 3/22. 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 Gotogate is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/137:15 pm
ORD
-
LHR
1 stop20h 25m
Scandinavian Airlines
Tue 10/206:40 am
LHR
-
ORD
1 stop15h 30m
Scandinavian Airlines
Deal found 3/22$642
This Ticket deal was found by Cheapflights users on 3/21. 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 Ticket is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 5/31:46 pm
STL
-
LHR
1 stop11h 24m
Virgin Atlantic
Tue 5/128:40 am
LHR
-
STL
2 stops20h 41m
Virgin Atlantic
Deal found 3/21$779
This Cheapflightsfares deal was found by Cheapflights users on 3/22. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/286:55 pm
STL
-
LHR
2 stops17h 30m
Lufthansa
Wed 5/610:50 am
LHR
-
STL
2 stops17h 55m
Lufthansa
Deal found 3/22$785

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 March 23, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$621
(Gotogate)

One-way from

$367
(Virgin Atlantic)

Popular in

June

Cheapest in

February

Average price

$707

Good round-trip deal

$748 or less

Good one-way deal

$423 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 ($200 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 March 2026
Search Deals
Price to beat on a round-trip flight from Illinois to London Heathrow.
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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 March 23, 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

ChicagoLondon

ORD - LHR

ORDLHR

Chicago O'Hare Intl

Mon 4/6

6:10 pm-8:30 am

Nonstop8h 20m

London Heathrow

Thu 4/16

6:50 am-12:00 pm

1 stop11h 10m

$806

ChicagoLondon

ORD - LHR

ORDLHR

Chicago O'Hare Intl

Mon 5/4

9:15 pm-11:15 am

Nonstop8h 00m

London Heathrow

Tue 5/12

7:30 am-5:50 pm

1 stop16h 20m

$806

ChicagoLondon

ORD - LHR

ORDLHR

Chicago O'Hare Intl

Tue 4/7

4:25 pm-6:45 am

Nonstop8h 20m

London Heathrow

Tue 4/14

6:50 am-12:00 pm

1 stop11h 10m

$806

ChicagoLondon

ORD - LHR

ORDLHR

Chicago O'Hare Intl

Sun 4/26

7:45 pm-1:15 pm

1 stop11h 30m

London Heathrow

Tue 5/5

6:30 am-4:18 pm

2 stops15h 48m

$820

ChicagoLondon

ORD - LHR

ORDLHR

Chicago O'Hare Intl

Wed 5/6

1:06 pm-6:20 am

1 stop11h 14m

London Heathrow

Fri 5/15

8:40 am-7:20 pm

2 stops16h 40m

$821

MolineLondon

MLI - LHR

MLILHR

Moline Quad-City

Tue 4/21

1:55 pm-6:45 am

1 stop10h 50m

London Heathrow

Tue 4/28

6:55 am-5:06 pm

2 stops16h 11m

$823

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Tue 4/21

4:41 pm-12:05 pm

2 stops13h 24m

London Heathrow

Tue 4/28

6:30 am-2:29 pm

2 stops13h 59m

$827

MolineLondon

MLI - LHR

MLILHR

Moline Quad-City

Wed 5/6

6:35 am-6:30 am

2 stops17h 55m

London Heathrow

Wed 5/13

7:25 am-4:51 pm

2 stops15h 26m

$827
Quickest round-trip

ChicagoLondon

ORD - LHR

ORDLHR

Chicago O'Hare Intl

Mon 4/13

6:10 pm-8:30 am

Nonstop8h 20m

London Heathrow

Tue 4/21

2:10 pm-5:20 pm

Nonstop9h 10m

$835

PeoriaLondon

PIA - LHR

PIALHR

Greater Peoria

Wed 8/12

6:30 pm-12:15 pm

1 stop11h 45m

London Heathrow

Wed 8/19

12:15 pm-11:21 pm

1 stop17h 06m

$846

Flights are sorted by cheapest round-trip flights first.

Deals found on 3/18

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, 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 $887). 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 March 23, 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 March 23, 2026.

The most flights from USIL to LHR are scheduled on a Monday (45 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (42 on average).

How much does it cost to fly round-trip 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 $806, United Airlines can have you in London Heathrow Airport from Illinois in 8h. 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 (80%), Air Canada (77%) or Austrian Airlines (77%) 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 $2,281, our data shows the cheapest flight currently is $336. When looking at the most popular route, (Chicago O'Hare Intl - London Heathrow), you can expect to pay $608 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 $887). 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
Hounslow
Croydon
Gatwick
Southend-on-Sea
Harrow
Eastleigh
Dartford
Dover
Winchester
Orpington
Watford
Northampton
Borehamwood
Broadway
Chipping Norton
Hayes
Kingston upon Thames
Eastbourne
Sutton

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 March 23, 2026.
AirlineCheapestAverageFlexibilityOn-time
JetBlueCheapest$51Average$432FlexibilityNo cancel feeOn-time62%
Scandinavian AirlinesCheapest$321Average$554FlexibilityNo cancel feeOn-time77%
DeltaCheapest$345Average$732FlexibilityNo cancel feeOn-timeN/A
SWISSCheapest$377Average$677FlexibilityNo cancel feeOn-time79%
TAP AIR PORTUGALCheapest$428Average$675FlexibilityNo cancel feeOn-timeN/A
IcelandairCheapest$477Average$579FlexibilityNo cancel feeOn-time76%
Aer LingusCheapest$481Average$807FlexibilityNo cancel feeOn-timeN/A
FinnairCheapest$516Average$802FlexibilityNo cancel feeOn-time76%
Alaska AirlinesCheapest$522Average$809FlexibilityNo cancel feeOn-time75%
British AirwaysCheapest$536Average$819FlexibilityNo cancel feeOn-time70%

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