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

Departing from London Heathrow Airport to Illinois will take you 13h 15m. The distance from London Heathrow Airport to Illinois is about 3939 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 £318 on Aer Lingus. Other airlines that offer cheap prices include Austrian Airlines from £325 and Icelandair from £328 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 £381. While the most popular route (London Heathrow - Chicago O'Hare Intl) can be booked for £417 on average, our data indicates £1,568 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 (88%), Austrian Airlines (88%), United Airlines( 88%).

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 Icelandair 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.

£362+ Cheap Flights from London Heathrow Airport to Illinois

Cheap flight deals from Heathrow to Illinois

Enter your travel dates to find the best prices.

Cheapest

Best

Direct

Last-minute

One-way

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 20 October 2026.

Thu 3/1206:40 -

1 stop16h 05m

Thu 10/1219:10 -

1 stop14h 50m

Deal found 19/10£514

Wed 4/1106:00 -

1 stop15h 30m

Sun 8/1120:10 -

1 stop20h 30m

Deal found 19/10£517

Thu 10/1207:05 -

2 stops15h 40m

Sun 31/119:10 -

1 stop32h 10m

Deal found 19/10£518

Fri 11/1206:00 -

1 stop15h 30m

Wed 30/1219:00 -

1 stop20h 35m

Deal found 19/10£521

Mon 16/1110:20 -

1 stop12h 25m

Mon 30/1119:10 -

2 stops15h 15m

Deal found 19/10£523

Sun 20/1206:40 -

1 stop16h 05m

Wed 30/1219:10 -

1 stop14h 50m

Deal found 16/10£523

Wed 18/1110:20 -

1 stop12h 25m

Thu 26/1119:10 -

1 stop20h 30m

Deal found 16/10£524

Fri 11/1218:40 -

1 stop28h 05m

Wed 30/1219:10 -

2 stops17h 40m

Deal found 16/10£526

Mon 7/1208:55 -

1 stop13h 21m

Fri 15/117:25 -

1 stop12h 15m

Deal found 18/10£541

Mon 7/1212:40 -

1 stop16h 14m

Mon 11/117:25 -

1 stop12h 15m

Deal found 18/10£556

Wed 18/1107:05 -

3 stops22h 42m

Mon 23/1109:09 -

2 stops24h 51m

Deal found 19/10£556

Mon 16/1106:40 -

2 stops23h 07m

Mon 23/1109:09 -

2 stops26h 31m

Deal found 17/10£561

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 20 October 2026.

Sat 7/1112:25 -

1 stop33h 05m

Fri 13/1120:10 -

1 stop19h 25m

Deal found 18/10£619

Wed 25/1109:00 -

1 stop13h 15m

Thu 3/1221:50 -

Nonstop8h 10m

Deal found 17/10£619

Mon 16/1106:00 -

1 stop14h 00m

Mon 30/1117:45 -

Nonstop8h 10m

Deal found 16/10£620

Fri 8/120:35 -

1 stop26h 45m

Sun 10/118:30 -

1 stop10h 20m

Deal found 15/10£646

Tue 17/1106:30 -

2 stops15h 48m

Tue 1/1213:02 -

1 stop16h 38m

Deal found 18/10£677

Mon 1/310:00 -

2 stops18h 10m

Tue 9/309:55 -

1 stop15h 10m

Deal found 18/10£685

Mon 9/1115:40 -

Nonstop9h 05m

Wed 18/1117:10 -

Nonstop7h 45m

Deal found 18/10£729

Wed 2/1206:30 -

2 stops16h 15m

Wed 9/1217:30 -

1 stop12h 30m

Deal found 18/10£786

Tue 10/1107:05 -

2 stops15h 40m

Fri 20/1106:00 -

2 stops21h 20m

Deal found 15/10£804

Thu 3/1215:40 -

1 stop14h 42m

Thu 10/1215:12 -

1 stop14h 23m

Deal found 19/10£883

Mon 16/1113:30 -

1 stop12h 35m

Mon 30/1117:45 -

Nonstop8h 10m

Deal found 17/10£624

Mon 16/1112:40 -

1 stop16h 14m

Tue 24/1109:30 -

2 stops15h 50m

Deal found 16/10£687

Mon 16/1107:30 -

2 stops15h 47m

Wed 23/1221:20 -

1 stop30h 20m

Deal found 15/10£625

Fri 11/1211:20 -

1 stop12h 41m

Wed 23/1209:30 -

1 stop15h 20m

Deal found 15/10£695

Mon 16/1110:10 -

2 stops18h 44m

Mon 30/1112:30 -

1 stop12h 35m

Deal found 16/10£687

Mon 8/309:00 -

1 stop13h 15m

Mon 29/318:10 -

Nonstop8h 20m

Deal found 17/10£628

Fri 20/1111:20 -

1 stop12h 44m

Sat 28/1113:31 -

1 stop12h 14m

Deal found 16/10£727

Wed 2/1216:20 -

1 stop13h 55m

Wed 9/1218:04 -

1 stop11h 31m

Deal found 18/10£809

Wed 25/1106:20 -

2 stops17h 44m

Sun 29/1109:30 -

2 stops15h 35m

Deal found 15/10£691

Wed 9/1207:40 -

Nonstop9h 05m

Sat 16/115:45 -

Nonstop8h 10m

Deal found 18/10£680

Tue 17/1115:40 -

1 stop14h 30m

Tue 24/1115:01 -

1 stop14h 34m

Deal found 20/10£856

Fri 20/1111:20 -

1 stop12h 44m

Thu 26/1116:13 -

1 stop13h 27m

Deal found 20/10£720

Wed 6/111:10 -

1 stop11h 40m

Sun 10/115:45 -

Nonstop8h 10m

Deal found 15/10£698

Wed 11/1112:35 -

1 stop17h 35m

Sun 15/1115:11 -

1 stop14h 24m

Deal found 15/10£890

Fri 20/1111:20 -

2 stops17h 34m

Sat 28/1109:30 -

2 stops15h 35m

Deal found 17/10£754

Thu 5/1111:10 -

1 stop13h 15m

Mon 9/1121:50 -

Nonstop8h 10m

Deal found 17/10£718

Wed 27/109:00 -

2 stops15h 57m

Sat 30/110:40 -

2 stops16h 30m

Deal found 19/10£761

Mon 30/1112:05 -

2 stops55h 50m

Mon 7/1210:45 -

2 stops14h 55m

Deal found 16/10£800

Sat 14/1106:50 -

2 stops17h 02m

Mon 16/1110:40 -

2 stops13h 40m

Deal found 15/10£836

Thu 3/1214:50 -

2 stops30h 58m

Thu 10/1216:29 -

2 stops38h 21m

Deal found 19/10£4,635

Find flight deals from Heathrow to Illinois

Round-trip from	£514
One-way from	£362
Popular in	August
Cheapest in	February
Average price	£652
Good round-trip deal	£586 or less
Good one-way deal	£576 or less

Scandinavian Airlines
3/12-10/12
2 total stops
30h 55m total
London to Illinois

Search Deals

25/11-31/12
2 total stops
16h 40m total
London to Illinois

Search Deals

Highest demand for flights based on searches. 11% potential increase in price (£59 potential increase over avg. return price).

Search Deals

Cheapest flight prices on average. 2% potential price decrease (£10 potential savings vs. average return price).

Search Deals

Average for round-trip flights in October 2026

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

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

Cheapest return flight

LondonChicago

LHR London Heathrow - ORD Chicago O'Hare Intl

LHRORD

London Heathrow

Tue 1/12

09:00-16:15

1 stop13h 15m

Chicago O'Hare Intl

Wed 31/12

00:00-07:00

Nonstop0h 00m

£392

LondonChicago

LHR London Heathrow - ORD Chicago O'Hare Intl

LHRORD

London Heathrow

Wed 14/4

07:30-17:50

1 stop16h 20m

Chicago O'Hare Intl

Wed 31/12

00:00-07:00

Nonstop0h 00m

£393

LondonChicago

LHR London Heathrow - ORD Chicago O'Hare Intl

LHRORD

London Heathrow

Wed 2/12

06:50-18:41

2 stops17h 51m

Chicago O'Hare Intl

Wed 31/12

00:00-07:00

Nonstop0h 00m

£405

LondonChicago

LHR London Heathrow - ORD Chicago O'Hare Intl

LHRORD

London Heathrow

Fri 22/1

06:00-15:30

1 stop15h 30m

Chicago O'Hare Intl

Wed 31/12

00:00-07:00

Nonstop0h 00m

£414

Fastest return journey

LondonChicago

LHR London Heathrow - ORD Chicago O'Hare Intl

LHRORD

London Heathrow

Wed 3/3

07:40-10:45

Nonstop9h 05m

Chicago O'Hare Intl

Wed 31/12

00:00-07:00

Nonstop0h 00m

£434

LondonChicago

LHR London Heathrow - ORD Chicago O'Hare Intl

LHRORD

London Heathrow

Wed 14/4

11:05-14:10

Nonstop9h 05m

Chicago O'Hare Intl

Wed 31/12

00:00-07:00

Nonstop0h 00m

£435

LondonChicago

LHR London Heathrow - ORD Chicago O'Hare Intl

LHRORD

London Heathrow

Mon 18/1

07:50-10:55

Nonstop9h 05m

Chicago O'Hare Intl

Wed 31/12

00:00-07:00

Nonstop0h 00m

£435

LondonChicago

LHR London Heathrow - ORD Chicago O'Hare Intl

LHRORD

London Heathrow

Wed 20/1

10:25-13:45

Nonstop9h 20m

Chicago O'Hare Intl

Wed 31/12

00:00-07:00

Nonstop0h 00m

£435

LondonChicago

LHR London Heathrow - MDW Chicago Midway

LHRMDW

London Heathrow

Wed 9/12

06:30-16:50

2 stops16h 20m

Chicago Midway

Wed 31/12

00:00-07:00

Nonstop0h 00m

£436

LondonChicago

LHR London Heathrow - ORD Chicago O'Hare Intl

LHRORD

London Heathrow

Wed 3/3

08:40-14:25

1 stop11h 45m

Chicago O'Hare Intl

Wed 31/12

00:00-07:00

Nonstop0h 00m

£440

Flights are sorted by cheapest return flights first.

Deals found on 18/10

Showing 1-10 of 56 resultsSorted by cheapest first

...

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.

LHR-ORD

LHR-MDW

LHR-MLI

LHR-PIA

LHR-SPI

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

LHR-USIL

LHR-ORD

LHR-MDW

LHR-MLI

LHR-PIA

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 £505). Flying from London Heathrow Airport to Illinois in August is currently the most expensive (average of £833). 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 decide to fly out makes little to no difference towards the overall price you’ll pay on tickets.

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 £575 and £741 in December.
The cheapest return price found within the last 5 days was £514 on Scandinavian Airlines (3 Dec–10 Dec).

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

The price you pay for your flight from London Heathrow Airport to Illinois may vary depending on when you book. For the best chance of a lower fare, look to book 79 days in advance of your trip. Fares are likely to increase a fortnight or so before your departure date.

Reviews of airlines servicing Illinois

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

Scandinavian Airlines

7.4

Good

2,018 reviews

Check prices

Reviews

1 / 20

6.0

Good

siavash,Oct 2026

CPH - JFK

I was seated in premium economy and I didn’t feel the crew being attentive or a warm sense of hospitality, the plane was clean. The seats were comfortable.

Scandinavian Airlines

7.4

Good

2,018 reviews

Scandinavian Airlines

7.4

Good

2,018 reviews

Check prices

Reviews

1 / 20

6.0

Good

siavash,Oct 2026

CPH - JFK

I was seated in premium economy and I didn’t feel the crew being attentive or a warm sense of hospitality, the plane was clean. The seats were comfortable.

Aer Lingus

7.3

Good

1,846 reviews

Scandinavian Airlines

7.4

Good

2,018 reviews

Check prices

Reviews

1 / 20

6.0

Good

siavash,Oct 2026

CPH - JFK

I was seated in premium economy and I didn’t feel the crew being attentive or a warm sense of hospitality, the plane was clean. The seats were comfortable.

Icelandair

6.9

Okay

763 reviews

Scandinavian Airlines

7.4

Good

2,018 reviews

Check prices

Reviews

1 / 20

6.0

Good

siavash,Oct 2026

CPH - JFK

I was seated in premium economy and I didn’t feel the crew being attentive or a warm sense of hospitality, the plane was clean. The seats were comfortable.

Lufthansa

6.8

Okay

8,279 reviews

Scandinavian Airlines

7.4

Good

2,018 reviews

Check prices

Reviews

1 / 20

6.0

Good

siavash,Oct 2026

CPH - JFK

I was seated in premium economy and I didn’t feel the crew being attentive or a warm sense of hospitality, the plane was clean. The seats were comfortable.

British Airways

6.7

Okay

8,266 reviews

Scandinavian Airlines

7.4

Good

2,018 reviews

Check prices

Reviews

1 / 20

6.0

Good

siavash,Oct 2026

CPH - JFK

I was seated in premium economy and I didn’t feel the crew being attentive or a warm sense of hospitality, the plane was clean. The seats were comfortable.

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 13h 15m. The distance from London Heathrow Airport to Illinois is about 3939 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 £318 on Aer Lingus. Other airlines that offer cheap prices include Austrian Airlines from £325 and Icelandair from £328 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 (88%), Austrian Airlines (88%), United Airlines( 88%).
What are the cheapest flights from London Heathrow Airport to Illinois?
Looking at all options, your cheapest flight can be booked for £381. While the most popular route (London Heathrow - Chicago O'Hare Intl) can be booked for £417 on average, our data indicates £1,568 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 £505). Flying from London Heathrow Airport to Illinois in August is currently the most expensive (average of £833). 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

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Alternative routes for Heathrow to Illinois

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Stansted to John F Kennedy Intl flights

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Stansted to Boston flights

Gatwick to O'Hare Intl flights

London City to Dallas/Fort Worth flights

Heathrow to Sky Harbor Intl flights

Stansted to O'Hare Intl flights

Heathrow to Denver flights

Top 10 airlines flying from Heathrow to Illinois

Airline	Cheapest	Average	Flexibility	On-time
Virgin Atlantic	Cheapest£213	Average£655	FlexibilityNo cancel fee	On-time72%	Search Virgin Atlantic flights
Icelandair	Cheapest£385	Average£515	FlexibilityNo cancel fee	On-time76%	Search Icelandair flights
Scandinavian Airlines	Cheapest£389	Average£563	FlexibilityNo cancel fee	On-time77%	Search Scandinavian Airlines flights
TAP AIR PORTUGAL	Cheapest£390	Average£599	FlexibilityNo cancel fee	On-timeN/A	Search TAP AIR PORTUGAL flights
Brussels Airlines	Cheapest£409	Average£794	FlexibilityNo cancel fee	On-timeN/A	Search Brussels Airlines flights
British Airways	Cheapest£427	Average£695	FlexibilityNo cancel fee	On-time70%	Search British Airways flights
Finnair	Cheapest£431	Average£730	FlexibilityNo cancel fee	On-time76%	Search Finnair flights
American Airlines	Cheapest£436	Average£783	FlexibilityNo cancel fee	On-time71%	Search American Airlines flights
JetBlue	Cheapest£447	Average£688	FlexibilityNo cancel fee	On-time62%	Search JetBlue flights
Austrian Airlines	Cheapest£450	Average£698	FlexibilityNo cancel fee	On-time78%	Search Austrian Airlines flights

Fly with Cheapflights

How does Cheapflights help users find flights from Heathrow to Illinois?

Cheapflights helps you search for flights from Heathrow to Illinois via 900+ travel sites so you don’t have to. After performing a flight search, users can also filter their flight selection by filtering for price, number of stops, airlines, and so on.

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

Cheapflights taps into our reliable network of hundreds of airlines and travel agencies to find the best deals for flights from Heathrow to Illinois for you. Better yet — we are completely free to use.

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

Yes! Cheapflights helps users easily find flights from Heathrow to Illinois with no change fees.

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

Of course! You can now track prices for flights from Heathrow to Illinois and get an alert from Cheapflights when they change. Have a valid email address ready and click the bell icon next to the flight deals above to set up your price alerts.

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Cheap flights from London Heathrow Airport to Illinois from £362

This is the cheapest retur flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 25/11. Fares are subject to change and may not be available on all flights or dates of travel.

Cheap 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 20 October 2026.

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 20 October 2026.

Best flights from Heathrow to IllinoisDiscover 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 20 October 2026.

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 20 October 2026.

Direct flights from Heathrow to IllinoisExplore direct flight options from Heathrow to Illinois based on user searches, and compare prices and availability for your desired travel dates. Data last updated 20 October 2026.

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 20 October 2026.

Last-minute flights from Heathrow to IllinoisDiscover last-minute flight deals from Heathrow to Illinois. Data last updated 20 October 2026 and is based on user searches.

Discover last-minute flight deals from Heathrow to Illinois. Data last updated 20 October 2026 and is based on user searches.

One-way flights from Heathrow to IllinoisSearch for one-way flight options from Heathrow to Illinois. Find affordable one-way fares based on user searches. Data last updated 20 October 2026.

Search for one-way flight options from Heathrow to Illinois. Find affordable one-way fares based on user searches. Data last updated 20 October 2026.

Find flight deals from Heathrow to Illinois

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 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

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 20 October 2026.

When flying from London Heathrow Airport to Illinois, the time of day you decide to fly out makes little to no difference towards the overall price you’ll pay on tickets.

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 £575 and £741 in December.The cheapest return price found within the last 5 days was £514 on Scandinavian Airlines (3 Dec–10 Dec).

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

The price you pay for your flight from London Heathrow Airport to Illinois may vary depending on when you book. For the best chance of a lower fare, look to book 79 days in advance of your trip. Fares are likely to increase a fortnight or so before your departure date.

Reviews of airlines servicing Illinois

Read through reviews of airlines operating flights from London Heathrow Airport to Illinois, such as Scandinavian Airlines,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

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

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Heathrow and Illinois flights

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Heathrow to Illinois flights

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Top 10 airlines flying from Heathrow to Illinois

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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 20 October 2026.

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 20 October 2026.

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 20 October 2026.

Last-minute flights from Heathrow to Illinois
Discover last-minute flight deals from Heathrow to Illinois. Data last updated 20 October 2026 and is based on user searches.

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 20 October 2026.

London Heathrow Airport to Illinois flights typically cost between £575 and £741 in December.
The cheapest return price found within the last 5 days was £514 on Scandinavian Airlines (3 Dec–10 Dec).