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

For as low as £473, United Airlines can have you in London Heathrow Airport from Illinois in 8h 10m. 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 TAP AIR PORTUGAL, with whom users have recently found tickets for as low as £164. However, be on the lookout for offers from Lufthansa and British Airways, as they are both options that can get you from Illinois to London Heathrow Airport for a low price.

In terms of precipitation, rainfall in London Heathrow Airport ranges from 40.0 - 70.0 inches per month. January is typically the wettest month, when rainfall can reach 70.0 mm. July is typically the driest time to visit London Heathrow Airport when rainfall is around 40.0 mm.

If weather is an important factor for your trip to London Heathrow Airport, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 17.0 C. Travellers hoping to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 4.0 C).

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 cheapest flights from Illinois to London Heathrow Airport?

On average you can expect to pay £461 for a flight from Illinois to London Heathrow Airport. The cheapest flight overall is £227 while the most popular route, (Chicago O'Hare Intl - London Heathrow) is currently priced at £378.

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 Aer Lingus (69%), Air Canada (65%) or Austrian Airlines (65%) as they are the most reliable in getting you off to your destination on time.

What are the most popular airlines that fly from Illinois to London Heathrow Airport?

Consider British Airways, Iberia or Aer Lingus when booking your flight. These represent the most popular airlines when flying from Illinois to London Heathrow Airport.

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.

£203+ Flights from Illinois to London Heathrow Airport

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

Airfare is below average for this route at the moment. Illinois to London Heathrow Airport flights typically cost between £466 and £636 in April. The cheapest return flight price found within the last 3 days was £405 on Icelandair (18 Apr-7 May).

Cheap flight deals from Illinois to Heathrow

Enter your travel dates to find the best prices.

Cheapest

Best

Direct

Last-minute

One-way

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 25 February 2026.

Sat 18/419:25

ORD

LHR

1 stop10h 30m

Icelandair

Thu 7/513:05

LHR

ORD

1 stop11h 10m

Icelandair

Deal found 23/2£405

Tue 7/419:25

ORD

LHR

1 stop10h 30m

Icelandair

Tue 12/521:25

LHR

ORD

1 stop26h 50m

Icelandair

Deal found 23/2£405

Mon 13/419:25

ORD

LHR

1 stop10h 30m

Icelandair

Sat 9/521:25

LHR

ORD

1 stop30h 00m

Icelandair

Deal found 23/2£406

Tue 7/419:25

ORD

LHR

1 stop10h 30m

Icelandair

Sat 18/421:25

LHR

ORD

1 stop30h 00m

Icelandair

Deal found 23/2£408

Fri 17/422:25

ORD

LHR

1 stop15h 55m

Icelandair

Fri 24/413:05

LHR

ORD

1 stop14h 20m

Icelandair

Deal found 23/2£408

Sun 1/320:25

ORD

LHR

1 stop20h 15m

TAP AIR PORTUGAL

Tue 10/318:30

LHR

ORD

1 stop26h 30m

TAP AIR PORTUGAL

Deal found 24/2£409

Wed 19/819:25

ORD

LHR

1 stop10h 30m

Icelandair

Thu 27/813:05

LHR

ORD

1 stop11h 10m

Icelandair

Deal found 22/2£410

Sun 1/320:25

ORD

LHR

1 stop20h 15m

TAP AIR PORTUGAL

Sat 7/318:30

LHR

ORD

1 stop26h 15m

TAP AIR PORTUGAL

Deal found 21/2£410

Tue 18/819:25

ORD

LHR

1 stop10h 30m

Icelandair

Tue 25/813:05

LHR

ORD

1 stop11h 10m

Icelandair

Deal found 21/2£411

Wed 19/819:25

ORD

LHR

1 stop10h 30m

Icelandair

Wed 26/821:25

LHR

ORD

1 stop26h 50m

Icelandair

Deal found 21/2£412

Wed 19/819:25

ORD

LHR

1 stop10h 30m

Icelandair

Sun 23/821:25

LHR

ORD

1 stop30h 00m

Icelandair

Deal found 23/2£413

Sat 15/822:25

ORD

LHR

1 stop31h 30m

Icelandair

Wed 26/821:25

LHR

ORD

1 stop26h 50m

Icelandair

Deal found 21/2£413

Best flights from Illinois to Heathrow
Discover carefully curated flight deals from Illinois to Heathrow that have cost, travel time, and stopovers in mind to ensure you get the best travel experience. Data last updated 25 February 2026.

Tue 24/316:45

ORD

LHR

Nonstop8h 10m

United Airlines

Tue 31/317:50

LHR

ORD

1 stop24h 10m

United Airlines

Deal found 23/2£473

Wed 8/413:37

ORD

LHR

1 stop10h 43m

Delta

Wed 22/408:40

LHR

ORD

2 stops15h 33m

Delta

Deal found 23/2£485

Tue 7/414:13

CMI

LHR

2 stops14h 22m

Iberia

Tue 14/406:15

LHR

CMI

2 stops18h 13m

Iberia

Deal found 21/2£488

Tue 7/414:38

CMI

LHR

1 stop14h 37m

British Airways

Tue 14/406:15

LHR

CMI

2 stops18h 13m

British Airways

Deal found 21/2£493

Wed 25/312:04

STL

LHR

2 stops13h 46m

Virgin Atlantic

Wed 1/409:40

LHR

STL

2 stops17h 02m

Virgin Atlantic

Deal found 24/2£510

Fri 1/512:51

MLI

LHR

1 stop16h 24m

Multiple Airlines

Sat 9/511:10

LHR

MLI

1 stop13h 00m

Multiple Airlines

Deal found 22/2£581

Tue 7/410:12

STL

LHR

2 stops25h 28m

Scandinavian Airlines

Tue 14/407:05

LHR

STL

3 stops20h 14m

Scandinavian Airlines

Deal found 24/2£668

Sat 21/312:02

BMI

LHR

1 stop14h 48m

KLM

Sun 29/308:40

LHR

BMI

2 stops19h 39m

KLM

Deal found 22/2£962

Wed 8/419:20

MDW

LHR

1 stop11h 45m

Delta

Wed 22/408:40

LHR

MDW

2 stops15h 56m

Delta

Deal found 21/2£485

Wed 1/413:20

PIA

LHR

1 stop11h 25m

United Airlines

Wed 8/406:50

LHR

PIA

2 stops21h 52m

United Airlines

Deal found 21/2£485

Sun 19/417:00

ORD

LHR

Nonstop7h 50m

British Airways

Tue 28/413:10

LHR

ORD

Nonstop8h 45m

British Airways

Deal found 24/2£494

Tue 7/413:20

PIA

LHR

1 stop11h 25m

United Airlines

Tue 14/406:50

LHR

PIA

2 stops21h 52m

United Airlines

Deal found 21/2£485

Wed 25/315:05

STL

LHR

1 stop11h 00m

Delta

Wed 1/408:40

LHR

STL

2 stops18h 02m

Delta

Deal found 24/2£493

Wed 8/411:19

EVV

LHR

2 stops18h 01m

Virgin Atlantic

Wed 15/409:20

LHR

EVV

1 stop13h 58m

Virgin Atlantic

Deal found 22/2£556

Mon 30/318:05

STL

LHR

1 stop33h 35m

United Airlines

Tue 14/414:10

LHR

STL

1 stop31h 14m

United Airlines

Deal found 24/2£496

Wed 22/412:52

MDW

LHR

1 stop12h 23m

Virgin Atlantic

Wed 29/415:15

LHR

MDW

1 stop13h 13m

Virgin Atlantic

Deal found 23/2£558

Thu 2/413:10

MDW

LHR

1 stop12h 00m

Delta

Wed 8/412:25

LHR

MDW

1 stop12h 15m

Delta

Deal found 22/2£542

Mon 30/313:20

PIA

LHR

1 stop13h 10m

United Airlines

Wed 8/414:10

LHR

PIA

1 stop12h 58m

United Airlines

Deal found 22/2£507

Fri 8/513:59

MDW

LHR

1 stop17h 06m

Virgin Atlantic

Mon 11/509:20

LHR

MDW

1 stop17h 49m

Virgin Atlantic

Deal found 21/2£579

Tue 24/312:50

ORD

LHR

1 stop13h 20m

United Airlines

Fri 17/414:10

LHR

ORD

Nonstop9h 10m

United Airlines

Deal found 24/2£513

Sat 18/419:16

MDW

LHR

1 stop11h 49m

Virgin Atlantic

Sat 25/410:40

LHR

MDW

2 stops17h 48m

Virgin Atlantic

Deal found 21/2£583

Thu 21/507:00

ORD

LHR

1 stop18h 10m

Delta

Mon 25/508:40

LHR

ORD

1 stop11h 50m

Delta

Deal found 24/2£611

Mon 23/321:39

ORD

LHR

1 stop31h 01m

United Airlines

Sun 29/309:30

LHR

ORD

1 stop31h 23m

United Airlines

Deal found 22/2£518

Fri 10/409:35

MDW

LHR

2 stops15h 10m

Virgin Atlantic

Sun 19/411:15

LHR

MDW

1 stop17h 13m

Virgin Atlantic

Deal found 24/2£583

Wed 29/718:32

CMI

LHR

1 stop9h 58m

British Airways

Sun 9/814:45

LHR

CMI

1 stop12h 52m

British Airways

Deal found 24/2£833

Wed 18/318:45

ORD

LHR

Nonstop8h 10m

United Airlines

Mon 30/311:05

LHR

ORD

Nonstop9h 05m

United Airlines

Deal found 21/2£521

Sat 11/413:10

MDW

LHR

2 stops16h 00m

Virgin Atlantic

Sat 18/410:45

LHR

MDW

2 stops17h 43m

Virgin Atlantic

Deal found 24/2£589

Fri 10/406:30

MLI

LHR

2 stops18h 00m

United Airlines

Fri 17/406:55

LHR

MLI

2 stops16h 11m

United Airlines

Deal found 24/2£533

Sat 15/816:30

STL

LHR

1 stop35h 10m

United Airlines

Sat 29/817:40

LHR

STL

1 stop26h 22m

United Airlines

Deal found 22/2£533

Thu 26/309:30

MDW

LHR

1 stop16h 35m

Virgin Atlantic

Thu 2/415:15

LHR

MDW

1 stop13h 16m

Virgin Atlantic

Deal found 24/2£677

Find flight deals from Illinois to Heathrow

Round-trip from	£405
One-way from	£203
Popular in	June
Cheapest in	September
Average price	£491
Good round-trip deal	£533 or less
Good one-way deal	£286 or less

Icelandair
18/4-7/5
2 total stops
21h 40m total
Illinois to London

Search Deals

Virgin Atlantic
23/7
1 total stop
19h 14m total
Illinois to London

Search Deals

Highest demand for flights based on searches. 21% potential increase in price (£114 potential increase over avg. return price).

Search Deals

Cheapest flight prices on average. 5% potential price decrease (£21 potential savings vs. average return 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

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

ChicagoLondon

ORD - LHR

ORDLHR

Chicago O'Hare Intl

Tue 24/3

16:45-05:55

Nonstop8h 10m

London Heathrow

Tue 31/3

17:50-12:00

1 stop24h 10m

£473

ChicagoLondon

ORD - LHR

ORDLHR

Chicago O'Hare Intl

Wed 8/4

13:37-06:20

1 stop10h 43m

London Heathrow

Wed 22/4

08:40-18:13

2 stops15h 33m

£485

ChicagoLondon

MDW - LHR

MDWLHR

Chicago Midway

Wed 8/4

19:20-13:05

1 stop11h 45m

London Heathrow

Wed 22/4

08:40-18:36

2 stops15h 56m

£485

PeoriaLondon

PIA - LHR

PIALHR

Greater Peoria

Wed 1/4

13:20-06:45

1 stop11h 25m

London Heathrow

Wed 8/4

06:50-22:42

2 stops21h 52m

£485

PeoriaLondon

PIA - LHR

PIALHR

Greater Peoria

Tue 7/4

13:20-06:45

1 stop11h 25m

London Heathrow

Tue 14/4

06:50-22:42

2 stops21h 52m

£485

ChampaignLondon

CMI - LHR

CMILHR

Champaign University-Willard

Tue 7/4

14:13-10:35

2 stops14h 22m

London Heathrow

Tue 14/4

06:15-18:28

2 stops18h 13m

£488

ChampaignLondon

CMI - LHR

CMILHR

Champaign University-Willard

Tue 7/4

14:38-11:15

1 stop14h 37m

London Heathrow

Tue 14/4

06:15-18:28

2 stops18h 13m

£493

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Wed 25/3

15:05-07:05

1 stop11h 00m

London Heathrow

Wed 1/4

08:40-20:42

2 stops18h 02m

£493

ChicagoLondon

ORD - LHR

ORDLHR

Chicago O'Hare Intl

Sun 19/4

17:00-06:50

Nonstop7h 50m

London Heathrow

Tue 28/4

13:10-15:55

Nonstop8h 45m

£494

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Mon 30/3

18:05-09:40

1 stop33h 35m

London Heathrow

Tue 14/4

14:10-15:24

1 stop31h 14m

£496

Flights are sorted by cheapest return flights first.

Deals found on 24/2

Showing 1-10 of 60 results

...

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.

ORD-LHR

MDW-LHR

BMI-LHR

STL-LHR

PIA-LHR

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

USIL-LHR

ORD-LHR

MDW-LHR

BMI-LHR

STL-LHR

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 £290). Flying from Illinois to London Heathrow Airport in June is currently the most expensive (average of £658). 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?

When flying from Illinois to London Heathrow Airport, 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 Illinois to London Heathrow Airport

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

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

Related info for your journey

How long is the flight from Illinois to London Heathrow Airport?
For as low as £473, United Airlines can have you in London Heathrow Airport from Illinois in 8h 10m. 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 TAP AIR PORTUGAL, with whom users have recently found tickets for as low as £164. However, be on the lookout for offers from Lufthansa and British Airways, 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 Aer Lingus (69%), Air Canada (65%) or Austrian Airlines (65%) 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 £461 for a flight from Illinois to London Heathrow Airport. The cheapest flight overall is £227 while the most popular route, (Chicago O'Hare Intl - London Heathrow) is currently priced at £378.
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 £290). Flying from Illinois to London Heathrow Airport in June is currently the most expensive (average of £658). 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.

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Top 7 airlines flying from Illinois to Heathrow

Airline	Cheapest	Average	Flexibility	On-time
Lufthansa	Cheapest£356	Average£512	FlexibilityNo cancel fee	On-time76%	Search Lufthansa flights
American Airlines	Cheapest£384	Average£610	FlexibilityNo cancel fee	On-time71%	Search American Airlines flights
Finnair	Cheapest£412	Average£573	FlexibilityNo cancel fee	On-time76%	Search Finnair flights
British Airways	Cheapest£421	Average£583	FlexibilityNo cancel fee	On-time70%	Search British Airways flights
Aer Lingus	Cheapest£447	Average£577	FlexibilityNo cancel fee	On-timeN/A	Search Aer Lingus flights
United Airlines	Cheapest£460	Average£692	FlexibilityNo cancel fee	On-time69%	Search United Airlines flights
Iberia	Cheapest£469	Average£532	FlexibilityNo cancel fee	On-time77%	Search Iberia flights

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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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Cheap flights from Illinois to London Heathrow Airport from £203

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 23/7. Fares are subject to change and may not be available on all flights or dates of travel.

Cheap flight deals from Illinois to Heathrow

Cheapest flights from Illinois to HeathrowExplore 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 25 February 2026.

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 25 February 2026.

Best flights from Illinois to HeathrowDiscover carefully curated flight deals from Illinois to Heathrow that have cost, travel time, and stopovers in mind to ensure you get the best travel experience. Data last updated 25 February 2026.

Discover carefully curated flight deals from Illinois to Heathrow that have cost, travel time, and stopovers in mind to ensure you get the best travel experience. Data last updated 25 February 2026.

Direct flights from Illinois to HeathrowExplore direct flight options from Illinois to Heathrow based on user searches, and compare prices and availability for your desired travel dates. Data last updated 25 February 2026.

Explore direct flight options from Illinois to Heathrow based on user searches, and compare prices and availability for your desired travel dates. Data last updated 25 February 2026.

Last-minute flights from Illinois to HeathrowDiscover last-minute flight deals from Illinois to Heathrow. Data last updated 25 February 2026 and is based on user searches.

Discover last-minute flight deals from Illinois to Heathrow. Data last updated 25 February 2026 and is based on user searches.

One-way flights from Illinois to HeathrowSearch for one-way flight options from Illinois to Heathrow. Find affordable one-way fares based on user searches. Data last updated 25 February 2026.

Search for one-way flight options from Illinois to Heathrow. Find affordable one-way fares based on user searches. Data last updated 25 February 2026.

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 25 February 2026.

Round-trip from

One-way from

Popular in

Cheapest in

Average price

Good round-trip deal

Good one-way deal

Cheapflights Fare Finder

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

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.

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?

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 25 February 2026.

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 25 February 2026.

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?

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

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

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

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

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

How can I find direct flights from Illinois to Heathrow?

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

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

Travelling to a place near London Heathrow Airport?

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Alternative routes for Illinois to Heathrow

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Other flights to Heathrow

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Illinois and Heathrow flights

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Illinois to Heathrow flights

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Top 7 airlines flying from Illinois to Heathrow

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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 25 February 2026.

Best flights from Illinois to Heathrow
Discover carefully curated flight deals from Illinois to Heathrow that have cost, travel time, and stopovers in mind to ensure you get the best travel experience. Data last updated 25 February 2026.

Direct flights from Illinois to Heathrow
Explore direct flight options from Illinois to Heathrow based on user searches, and compare prices and availability for your desired travel dates. Data last updated 25 February 2026.

Last-minute flights from Illinois to Heathrow
Discover last-minute flight deals from Illinois to Heathrow. Data last updated 25 February 2026 and is based on user searches.

One-way flights from Illinois to Heathrow
Search for one-way flight options from Illinois to Heathrow. Find affordable one-way fares based on user searches. Data last updated 25 February 2026.