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

Departing from London Heathrow Airport to Illinois will take you 17h 38m. The distance from London Heathrow Airport to Illinois is about 3942 mi. Both multi-stop and direct flights can be found to your destination and back.

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

One-way options have recently been found by users for as low as £337 on British Airways. Other airlines that offer cheap prices include Delta from £376 and American Airlines from £401 one-way.

In terms of precipitation, rainfall in Illinois ranges from 43.0 - 125.0 inches per month. August is typically the wettest month, when rainfall can reach 125.0 mm. January is typically the driest time to visit Illinois when rainfall is around 43.0 mm.

If weather is an important factor for your trip to Illinois, 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 23.0 C. Travellers hoping to avoid the cold should look outside of January, when temperatures are typically at their lowest (around -5.0 C).

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

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

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

Looking at all options, your cheapest flight can be booked for £400. While the most popular route (London Heathrow - Chicago O'Hare Intl) can be booked for £377 on average, our data indicates £1,259 when flying from London Heathrow Airport to Illinois.

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

Before booking your flight to Illinois from London Heathrow Airport, check out the most reliable airlines to get you to your destination on time: Air Canada (84%), Austrian Airlines (84%), United Airlines( 84%).

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

When booking a flight from London Heathrow Airport to Illinois, you may want to consider flying on British Airways, Lufthansa or Finnair as they are the most popular for this route.

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

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

How can I find direct flights from Heathrow to Illinois?

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

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

Yes. Cheapflights offers flight deals from Heathrow to Illinois by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

£337+ Cheap Flights from London Heathrow Airport to Illinois

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

Airfare is below average for this route at the moment. London Heathrow Airport to Illinois flights typically cost between £477 and £678 in November. The cheapest return flight price found within the last 3 days was £396 on Scandinavian Airlines (10 Nov-17 Nov).

Cheap flight deals from Heathrow to Illinois

Round-trip from	£396
One-way from	£337
Popular in	July
Cheapest in	February
Average price	£536
Good round-trip deal	£493 or less
Good one-way deal	£468 or less

Scandinavian Airlines
10/11-17/11
2 total stops
33h 15m total
London to Illinois

Search Deals

British Airways
18/2
2 total stops
17h 53m total
London to Illinois

Search Deals

Highest demand for flights based on searches. 13% potential increase in price (£61 potential increase over avg. return price).

Search Deals

Cheapest flight prices on average. 2% potential price decrease (£9 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 London Heathrow to Illinois.

Search Deals

Price to beat on a one-way flight from London Heathrow to Illinois.

Search Deals

Find flight deals from Heathrow to Illinois

Enter your travel dates to find the best prices.

Cheapest flights from Heathrow to Illinois
Explore the most affordable flight options available from Heathrow to Illinois. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 17 October 2025.

Mon 10/1106:40LHR - ORD

1 stop16h 05mScandinavian Airlines

Mon 17/1119:20ORD - LHR

1 stop17h 10mScandinavian Airlines

Deal found 17/10£396

Wed 12/1118:40LHR - ORD

1 stop28h 05mScandinavian Airlines

Wed 19/1119:20ORD - LHR

1 stop14h 40mScandinavian Airlines

Deal found 15/10£397

Tue 18/1119:50LHR - ORD

2 stops26h 55mScandinavian Airlines

Thu 27/1119:20ORD - LHR

1 stop16h 20mScandinavian Airlines

Deal found 15/10£398

Wed 12/1119:30LHR - ORD

1 stop27h 15mScandinavian Airlines

Sun 16/1119:20ORD - LHR

2 stops15h 05mScandinavian Airlines

Deal found 17/10£399

Mon 3/1107:05LHR - ORD

2 stops15h 40mScandinavian Airlines

Sat 8/1119:20ORD - LHR

1 stop20h 20mScandinavian Airlines

Deal found 15/10£400

Sat 1/1106:40LHR - ORD

1 stop16h 05mScandinavian Airlines

Sat 22/1119:20ORD - LHR

1 stop20h 20mScandinavian Airlines

Deal found 17/10£401

Mon 10/1110:20LHR - ORD

1 stop12h 25mScandinavian Airlines

Fri 14/1119:20ORD - LHR

2 stops15h 05mScandinavian Airlines

Deal found 15/10£401

Sat 1/1106:40LHR - ORD

1 stop16h 05mScandinavian Airlines

Wed 5/1119:20ORD - LHR

2 stops17h 30mScandinavian Airlines

Deal found 15/10£402

Fri 7/1110:20LHR - ORD

1 stop12h 25mScandinavian Airlines

Wed 19/1119:20ORD - LHR

2 stops15h 05mScandinavian Airlines

Deal found 15/10£403

Mon 10/1106:40LHR - ORD

1 stop16h 05mScandinavian Airlines

Mon 24/1119:20ORD - LHR

1 stop17h 10mScandinavian Airlines

Deal found 15/10£404

Mon 17/1106:40LHR - ORD

1 stop16h 05mScandinavian Airlines

Mon 1/1219:20ORD - LHR

2 stops15h 05mScandinavian Airlines

Deal found 15/10£404

Thu 13/1112:15LHR - MDW

2 stops17h 40mMultiple Airlines

Thu 20/1106:20MDW - LHR

2 stops31h 10mMultiple Airlines

Deal found 16/10£463

Best flights from Heathrow to Illinois
Discover carefully curated flight deals from Heathrow to Illinois that have cost, travel time, and stopovers in mind to ensure you get the best travel experience. Data last updated 17 October 2025.

Thu 6/1118:40LHR - ORD

1 stop28h 05mScandinavian Airlines

Thu 13/1119:20ORD - LHR

1 stop20h 20mScandinavian Airlines

Deal found 16/10£409

Thu 13/1113:45LHR - ORD

1 stop32h 35mUnited Airlines

Sat 15/1115:55ORD - LHR

1 stop32h 35mUnited Airlines

Deal found 15/10£411

Mon 17/1106:30LHR - MDW

2 stops17h 38mDelta

Mon 1/1210:47MDW - LHR

1 stop13h 38mDelta

Deal found 15/10£514

Wed 12/1111:45LHR - MDW

2 stops17h 55mVirgin Atlantic

Wed 19/1110:47MDW - LHR

2 stops14h 03mVirgin Atlantic

Deal found 15/10£514

Mon 17/1108:20LHR - STL

1 stop14h 07mBritish Airways

Mon 1/1214:08STL - LHR

1 stop11h 12mBritish Airways

Deal found 16/10£540

Mon 24/1111:45LHR - STL

2 stops15h 01mKLM

Mon 1/1213:55STL - LHR

1 stop11h 55mKLM

Deal found 17/10£546

Thu 5/313:10LHR - STL

1 stop13h 08mAmerican Airlines

Mon 9/314:48STL - LHR

1 stop12h 02mAmerican Airlines

Deal found 16/10£578

Wed 12/1119:30LHR - ORD

1 stop27h 15mScandinavian Airlines

Sun 23/1119:20ORD - LHR

1 stop14h 40mScandinavian Airlines

Deal found 16/10£409

Mon 1/1210:45LHR - MLI

1 stop17h 50mMultiple Airlines

Mon 8/1217:08MLI - LHR

1 stop12h 32mMultiple Airlines

Deal found 17/10£854

Fri 14/1110:20LHR - ORD

1 stop12h 25mScandinavian Airlines

Fri 28/1119:20ORD - LHR

1 stop14h 40mScandinavian Airlines

Deal found 16/10£409

Thu 6/1117:30LHR - ORD

2 stops29h 15mScandinavian Airlines

Fri 14/1119:20ORD - LHR

1 stop14h 40mScandinavian Airlines

Deal found 16/10£412

Wed 12/1106:30LHR - MDW

2 stops17h 38mDelta

Wed 19/1113:47MDW - LHR

1 stop11h 18mDelta

Deal found 15/10£514

Mon 17/1115:50LHR - MDW

1 stop13h 50mVirgin Atlantic

Mon 1/1213:47MDW - LHR

1 stop11h 18mVirgin Atlantic

Deal found 15/10£527

Mon 24/1108:20LHR - STL

1 stop14h 07mBritish Airways

Sun 30/1119:58STL - LHR

1 stop28h 57mBritish Airways

Deal found 17/10£542

Thu 6/1117:30LHR - ORD

2 stops29h 15mScandinavian Airlines

Sun 16/1119:20ORD - LHR

2 stops15h 05mScandinavian Airlines

Deal found 16/10£415

Wed 19/1106:30LHR - MDW

2 stops16h 09mDelta

Wed 26/1110:47MDW - LHR

1 stop13h 38mDelta

Deal found 17/10£518

Thu 13/1111:45LHR - MDW

2 stops17h 55mVirgin Atlantic

Thu 20/1109:41MDW - LHR

1 stop15h 24mVirgin Atlantic

Deal found 16/10£546

Tue 18/1119:50LHR - ORD

2 stops26h 55mScandinavian Airlines

Wed 26/1119:20ORD - LHR

1 stop16h 20mScandinavian Airlines

Deal found 17/10£418

Tue 13/114:45LHR - STL

1 stop14h 27mBritish Airways

Fri 23/115:37STL - LHR

1 stop12h 23mBritish Airways

Deal found 17/10£561

Tue 25/1108:40LHR - MDW

2 stops15h 28mDelta

Wed 3/1212:50MDW - LHR

2 stops14h 30mDelta

Deal found 17/10£518

Fri 21/1119:50LHR - ORD

2 stops26h 55mScandinavian Airlines

Sun 7/1219:20ORD - LHR

2 stops17h 30mScandinavian Airlines

Deal found 16/10£418

Mon 1/1217:50LHR - STL

2 stops32h 57mVirgin Atlantic

Mon 8/1211:40STL - LHR

2 stops14h 10mVirgin Atlantic

Deal found 17/10£558

Thu 13/1108:40LHR - MDW

2 stops15h 28mDelta

Thu 20/1109:41MDW - LHR

1 stop15h 24mDelta

Deal found 16/10£546

Sat 6/1210:20LHR - ORD

1 stop12h 25mScandinavian Airlines

Sun 7/1219:20ORD - LHR

1 stop17h 10mScandinavian Airlines

Deal found 14/10£421

Thu 20/1113:05LHR - STL

2 stops16h 39mVirgin Atlantic

Mon 8/1213:57STL - LHR

2 stops14h 53mVirgin Atlantic

Deal found 17/10£565

Mon 1/1206:50LHR - MLI

2 stops33h 25mUnited Airlines

Mon 8/1215:56MLI - LHR

2 stops12h 54mUnited Airlines

Deal found 17/10£767

Sat 22/1106:15LHR - SPI

2 stops17h 33mAmerican Airlines

Tue 25/1106:00SPI - LHR

2 stops20h 30mAmerican Airlines

Deal found 14/10£795

Sat 6/1208:40LHR - MDW

2 stops15h 38mDelta

Sun 7/1218:40MDW - LHR

1 stop32h 05mDelta

Deal found 16/10£549

Thu 30/1006:40LHR - ORD

1 stop17h 05mScandinavian Airlines

Sun 2/1119:20ORD - LHR

2 stops15h 05mScandinavian Airlines

Deal found 16/10£432

Thu 5/311:45LHR - STL

2 stops14h 54mVirgin Atlantic

Mon 9/315:50STL - LHR

1 stop10h 15mVirgin Atlantic

Deal found 16/10£581

Direct flights from Heathrow to Illinois
Explore direct flight options from Heathrow to Illinois based on user searches, and compare prices and availability for your desired travel dates. Data last updated 17 October 2025.

Mon 17/1110:25LHR - ORD

Nonstop9h 20mLufthansa

Mon 1/1221:05ORD - LHR

Nonstop8h 10mLufthansa

Deal found 15/10£457

Wed 12/1113:35LHR - ORD

Nonstop9h 25mLufthansa

Mon 17/1115:45ORD - LHR

Nonstop8h 10mLufthansa

Deal found 15/10£459

Wed 12/1113:35LHR - ORD

Nonstop9h 25mAustrian Airlines

Wed 11/215:45ORD - LHR

Nonstop8h 10mAustrian Airlines

Deal found 15/10£460

Mon 24/1107:55LHR - ORD

Nonstop9h 20mLufthansa

Tue 2/1215:45ORD - LHR

Nonstop8h 10mLufthansa

Deal found 16/10£462

Mon 17/1112:35LHR - ORD

Nonstop8h 50mBritish Airways

Mon 1/1217:10ORD - LHR

Nonstop7h 45mBritish Airways

Deal found 17/10£471

Wed 18/210:25LHR - ORD

Nonstop9h 20mAustrian Airlines

Tue 3/315:45ORD - LHR

Nonstop8h 10mAustrian Airlines

Deal found 15/10£471

Mon 17/1107:55LHR - ORD

Nonstop9h 20mAustrian Airlines

Mon 1/1215:45ORD - LHR

Nonstop8h 10mAustrian Airlines

Deal found 15/10£473

Tue 18/1110:25LHR - ORD

Nonstop9h 20mAustrian Airlines

Thu 27/1117:50ORD - LHR

Nonstop8h 05mAustrian Airlines

Deal found 15/10£474

Mon 17/1113:35LHR - ORD

Nonstop9h 25mAustrian Airlines

Tue 25/1115:45ORD - LHR

Nonstop8h 10mAustrian Airlines

Deal found 15/10£475

Tue 18/1110:25LHR - ORD

Nonstop9h 20mAustrian Airlines

Mon 24/1117:50ORD - LHR

Nonstop8h 05mAustrian Airlines

Deal found 15/10£476

Tue 25/1114:10LHR - ORD

Nonstop8h 50mBritish Airways

Wed 3/1217:10ORD - LHR

Nonstop7h 45mBritish Airways

Deal found 15/10£477

Last-minute flights from Heathrow to Illinois
Discover last-minute flight deals from Heathrow to Illinois. Data last updated 17 October 2025 and is based on user searches.

Sat 1/1106:40LHR - ORD

1 stop16h 05mScandinavian Airlines

Sat 22/1119:20ORD - LHR

1 stop20h 20mScandinavian Airlines

Deal found 17/10£401

Sat 1/1106:40LHR - ORD

1 stop16h 05mScandinavian Airlines

Wed 5/1119:20ORD - LHR

2 stops17h 30mScandinavian Airlines

Deal found 15/10£402

Mon 3/1107:05LHR - ORD

2 stops15h 40mScandinavian Airlines

Sat 8/1119:20ORD - LHR

1 stop20h 20mScandinavian Airlines

Deal found 15/10£400

Fri 7/1115:35LHR - ORD

2 stops31h 10mScandinavian Airlines

Fri 28/1119:20ORD - LHR

2 stops39h 05mScandinavian Airlines

Deal found 15/10£403

Mon 10/1106:40LHR - ORD

1 stop16h 05mScandinavian Airlines

Mon 17/1119:20ORD - LHR

1 stop17h 10mScandinavian Airlines

Deal found 17/10£396

Mon 10/1110:20LHR - ORD

1 stop12h 25mScandinavian Airlines

Fri 14/1119:20ORD - LHR

2 stops15h 05mScandinavian Airlines

Deal found 15/10£401

Mon 10/1106:40LHR - ORD

1 stop16h 05mScandinavian Airlines

Mon 24/1119:20ORD - LHR

1 stop17h 10mScandinavian Airlines

Deal found 15/10£404

Wed 12/1119:30LHR - ORD

1 stop27h 15mScandinavian Airlines

Wed 19/1119:20ORD - LHR

1 stop16h 20mScandinavian Airlines

Deal found 15/10£397

Wed 12/1119:30LHR - ORD

1 stop27h 15mScandinavian Airlines

Sun 16/1119:20ORD - LHR

2 stops15h 05mScandinavian Airlines

Deal found 17/10£399

Thu 13/1112:15LHR - MDW

2 stops17h 40mMultiple Airlines

Thu 20/1106:20MDW - LHR

2 stops31h 10mMultiple Airlines

Deal found 16/10£463

Mon 17/1106:40LHR - ORD

1 stop16h 05mScandinavian Airlines

Mon 1/1219:20ORD - LHR

2 stops15h 05mScandinavian Airlines

Deal found 15/10£404

Tue 18/1118:30LHR - ORD

1 stop26h 30mTAP AIR PORTUGAL

Fri 28/1120:15ORD - LHR

1 stop16h 40mTAP AIR PORTUGAL

Deal found 15/10£398

One-way flights from Heathrow to Illinois
Search for one-way flight options from Heathrow to Illinois. Find affordable one-way fares based on user searches. Data last updated 17 October 2025.

Wed 18/208:25LHR - STL

2 stops17h 53mBritish Airways

Deal found 17/10£337

Wed 18/206:00LHR - STL

3 stops33h 47mMultiple Airlines

Deal found 17/10£361

Wed 15/413:30LHR - STL

1 stop12h 33mMultiple Airlines

Deal found 16/10£367

Wed 15/406:30LHR - STL

2 stops16h 19mDelta

Deal found 16/10£376

Sat 14/307:30LHR - STL

2 stops19h 18mBritish Airways

Deal found 15/10£380

Sun 15/306:15LHR - STL

2 stops20h 33mBritish Airways

Deal found 17/10£382

Sun 7/1217:20LHR - STL

2 stops32h 09mMultiple Airlines

Deal found 15/10£388

Thu 25/1212:35LHR - ORD

Nonstop8h 50mIberia

Deal found 17/10£397

Tue 20/109:50LHR - MDW

3 stops33h 18mMultiple Airlines

Deal found 17/10£397

Sat 14/314:45LHR - STL

1 stop13h 47mMultiple Airlines

Deal found 15/10£398

Sat 8/1108:05LHR - ORD

1 stop18h 47mJetBlue

Deal found 16/10£398

Sun 16/1114:50LHR - ORD

2 stops29h 51mMultiple Airlines

Deal found 17/10£398

Cheapflights Fare Finder

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

Fly from

Fly to

Route

Depart

Return

Price

LondonChicago

LHR - ORD

LHRORD

London Heathrow

Thu 6/11

18:40-16:45

1 stop28h 05m

Chicago O'Hare Intl

Thu 13/11

19:20-21:40

1 stop20h 20m

£409

LondonChicago

LHR - ORD

LHRORD

London Heathrow

Wed 12/11

19:30-16:45

1 stop27h 15m

Chicago O'Hare Intl

Sun 23/11

19:20-16:00

1 stop14h 40m

£409

LondonChicago

LHR - ORD

LHRORD

London Heathrow

Fri 14/11

10:20-16:45

1 stop12h 25m

Chicago O'Hare Intl

Fri 28/11

19:20-16:00

1 stop14h 40m

£409

LondonChicago

LHR - ORD

LHRORD

London Heathrow

Thu 13/11

13:45-16:20

1 stop32h 35m

Chicago O'Hare Intl

Sat 15/11

15:55-06:30

1 stop32h 35m

£411

LondonChicago

LHR - ORD

LHRORD

London Heathrow

Thu 6/11

17:30-16:45

2 stops29h 15m

Chicago O'Hare Intl

Fri 14/11

19:20-16:00

1 stop14h 40m

£412

LondonChicago

LHR - ORD

LHRORD

London Heathrow

Thu 6/11

17:30-16:45

2 stops29h 15m

Chicago O'Hare Intl

Sun 16/11

19:20-16:25

2 stops15h 05m

£415

LondonChicago

LHR - ORD

LHRORD

London Heathrow

Tue 18/11

19:50-16:45

2 stops26h 55m

Chicago O'Hare Intl

Wed 26/11

19:20-17:40

1 stop16h 20m

£418

LondonChicago

LHR - ORD

LHRORD

London Heathrow

Fri 21/11

19:50-16:45

2 stops26h 55m

Chicago O'Hare Intl

Sun 7/12

19:20-18:50

2 stops17h 30m

£418

LondonChicago

LHR - ORD

LHRORD

London Heathrow

Sat 6/12

10:20-16:45

1 stop12h 25m

Chicago O'Hare Intl

Sun 7/12

19:20-18:30

1 stop17h 10m

£421

LondonChicago

LHR - ORD

LHRORD

London Heathrow

Thu 30/10

06:40-18:45

1 stop17h 05m

Chicago O'Hare Intl

Sun 2/11

19:20-16:25

2 stops15h 05m

£432

Flights are sorted by cheapest return flights first.

Deals found on 17/10

Showing 1-10 of 60 results

...

Best time to book a flight from Heathrow to Illinois

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

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

Currently, February is the cheapest month in which you can book a flight from London Heathrow Airport to Illinois (average of £356). Flying from London Heathrow Airport to Illinois in July is currently the most expensive (average of £501). 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 LHR to IL?

When flying from London Heathrow Airport to Illinois, the time of day you fly usually plays a role in the price. Save by searching for a flight in the evening, which can drop the price by up to 28% versus a flight in the afternoon.

What is the cheapest day to fly from London Heathrow Airport to Illinois?

Travellers seeking maximum savings on their London Heathrow Airport to Illinois flight should consider departing on Wednesday afternoons when fares are most often at their lowest. Sunday afternoons flights should be avoided if possible as fares are typically the most expensive at this time.

Weekly flight availability from London Heathrow Airport to Illinois

The most flights from LHR to USIL are scheduled on a Monday (47 on average). You will have fewer flight options on Monday, which is when the least amount of flights are scheduled (47 on average).

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

Reviews of airlines servicing Illinois

Read through reviews of airlines operating flights from London Heathrow Airport to Illinois, such as Finnair, Aer Lingus, andIcelandair. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.

Finnair

7.6

Good

1,332 reviews

Check prices

Reviews

1 / 20

10.0

Excellent

Anonymous,May 2025

FRA - DFW

I was lucky I had a seet without no one next to me My vegetarian meal was excellent. The service very good. Although there was a lot of turbulences during the flight, the landing was very soft and took away all our apprehension.

Finnair

7.6

Good

1,332 reviews

Finnair

7.6

Good

1,332 reviews

Check prices

Reviews

1 / 20

10.0

Excellent

Anonymous,May 2025

FRA - DFW

Aer Lingus

7.2

Good

1,341 reviews

Finnair

7.6

Good

1,332 reviews

Check prices

Reviews

1 / 20

10.0

Excellent

Anonymous,May 2025

FRA - DFW

Icelandair

7.0

Good

556 reviews

Finnair

7.6

Good

1,332 reviews

Check prices

Reviews

1 / 20

10.0

Excellent

Anonymous,May 2025

FRA - DFW

Lufthansa

6.8

Okay

7,500 reviews

Finnair

7.6

Good

1,332 reviews

Check prices

Reviews

1 / 20

10.0

Excellent

Anonymous,May 2025

FRA - DFW

British Airways

6.7

Okay

7,459 reviews

Finnair

7.6

Good

1,332 reviews

Check prices

Reviews

1 / 20

10.0

Excellent

Anonymous,May 2025

FRA - DFW

Related info for your journey

How long is the flight from London Heathrow Airport to Illinois?
Departing from London Heathrow Airport to Illinois will take you 17h 38m. The distance from London Heathrow Airport to Illinois is about 3942 mi. Both multi-stop and direct flights can be found to your destination and back.
What are the cheapest airlines to fly from London Heathrow Airport to Illinois one-way?
One-way options have recently been found by users for as low as £337 on British Airways. Other airlines that offer cheap prices include Delta from £376 and American Airlines from £401 one-way.
What are the most popular routes from London Heathrow Airport to Illinois?
The most popular flight routes from London Heathrow Airport to Illinois are London Heathrow - Chicago O'Hare Intl, London Heathrow - Chicago Midway and London Heathrow - Lambert-St Louis.
What are the most reliable airlines from London Heathrow Airport to Illinois?
Before booking your flight to Illinois from London Heathrow Airport, check out the most reliable airlines to get you to your destination on time: Air Canada (84%), Austrian Airlines (84%), United Airlines( 84%).
What are the cheapest flights from London Heathrow Airport to Illinois?
Looking at all options, your cheapest flight can be booked for £400. While the most popular route (London Heathrow - Chicago O'Hare Intl) can be booked for £377 on average, our data indicates £1,259 when flying from London Heathrow Airport to Illinois.
Can I find deals for flights from Heathrow to Illinois that include hotel bookings?
Yes. In addition to deals on Heathrow to Illinois flights, Cheapflights offers holiday packages that include both flights and hotel.
How can I find direct flights from Heathrow to Illinois?
After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Heathrow to Illinois.
Can I find deals for business class flights from Heathrow to Illinois?
Yes. Cheapflights offers flight deals from Heathrow to Illinois 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 London Heathrow Airport to Illinois?
Currently, February is the cheapest month in which you can book a flight from London Heathrow Airport to Illinois (average of £356). Flying from London Heathrow Airport to Illinois in July is currently the most expensive (average of £501). 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

Browse thousands of different options on Cheapflights for your next trip

Alternative routes for Heathrow to Illinois

Heathrow to John F Kennedy Intl flights

Heathrow to Newark flights

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Gatwick to Newark flights

Stansted to John F Kennedy Intl flights

Luton to John F Kennedy Intl flights

London City to Newark flights

Heathrow to Miami flights

Gatwick to LaGuardia flights

Stansted to Newark flights

Luton to Newark flights

Heathrow to Orlando flights

Heathrow to Los Angeles flights

Heathrow to Dulles Intl flights

Heathrow to Dallas/Fort Worth flights

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Complete your trip

Illinois car hire

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Direct flights to United States

Top 10 airlines flying from Heathrow to Illinois

Airline	Cheapest	Average	Flexibility	On-time
Icelandair	Cheapest£340	Average£453	FlexibilityNo cancel fee	On-time76%	Search Icelandair flights
Virgin Atlantic	Cheapest£345	Average£550	FlexibilityNo cancel fee	On-time72%	Search Virgin Atlantic flights
Scandinavian Airlines	Cheapest£356	Average£497	FlexibilityNo cancel fee	On-time77%	Search Scandinavian Airlines flights
Aer Lingus	Cheapest£368	Average£576	FlexibilityNo cancel fee	On-timeN/A	Search Aer Lingus flights
TAP AIR PORTUGAL	Cheapest£368	Average£613	FlexibilityNo cancel fee	On-timeN/A	Search TAP AIR PORTUGAL flights
Brussels Airlines	Cheapest£386	Average£541	FlexibilityNo cancel fee	On-timeN/A	Search Brussels Airlines flights
Lufthansa	Cheapest£396	Average£575	FlexibilityNo cancel fee	On-time76%	Search Lufthansa flights
Austrian Airlines	Cheapest£401	Average£589	FlexibilityNo cancel fee	On-time78%	Search Austrian Airlines flights
British Airways	Cheapest£404	Average£568	FlexibilityNo cancel fee	On-time70%	Search British Airways flights
United Airlines	Cheapest£408	Average£677	FlexibilityNo cancel fee	On-time69%	Search United Airlines flights

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Cheap flights from London Heathrow Airport to Illinois from £337

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 18/2. Fares are subject to change and may not be available on all flights or dates of travel.

Cheap flight deals from Heathrow to Illinois

Keep the following information in mind while searching for Heathrow to Illinois flight deals. Data was last updated 17 October 2025.

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Find flight deals from Heathrow to Illinois

Cheapest flights from Heathrow to IllinoisExplore the most affordable flight options available from Heathrow to Illinois. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 17 October 2025.

Explore the most affordable flight options available from Heathrow to Illinois. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 17 October 2025.

Cheapflights Fare Finder

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

Best time to book a flight from Heathrow to Illinois

Have a flexible travel schedule? Discover the best time to fly to Illinois from Heathrow with our price prediction graph.

Cheapflights Insights

Everything you need to know about your flight from London Heathrow Airport to Illinois

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

What is the cheapest time of day to fly from LHR to IL?

Find hourly flight availability from Heathrow to Illinois. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated 17 October 2025.

What is the cheapest day to fly from London Heathrow Airport to Illinois?

Use this chart to determine the cheapest time to fly return from Heathrow to Illinois. Price data was last updated on 16 December 2024.

Weekly flight availability from London Heathrow Airport to Illinois

Explore weekly flight availability from Heathrow to Illinois. 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 17 October 2025.

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

Reviews of airlines servicing Illinois

Read through reviews of airlines operating flights from London Heathrow Airport to Illinois, such as Finnair, Aer Lingus, andIcelandair. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.

Related info for your journey

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

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

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

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

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

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

How can I find direct flights from Heathrow to Illinois?

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

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

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Alternative routes for Heathrow to Illinois

See prices for flight routes from nearby airports that may be better suited for you.

Top 10 airlines flying from Heathrow to Illinois

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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 Heathrow to Illinois?

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

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

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

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Cheapest flights from Heathrow to Illinois
Explore the most affordable flight options available from Heathrow to Illinois. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 17 October 2025.