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

For as low as £525, Scandinavian Airlines can have you in London Heathrow Airport from Illinois in 15h 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 Lufthansa, with whom users have recently found tickets for as low as £278. However, be on the lookout for offers from British Airways and Iberia, 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 £1,340 for a flight from Illinois to London Heathrow Airport. The cheapest flight overall is £228 while the most popular route, (Chicago O'Hare Intl - London Heathrow) is currently priced at £395.

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 Air Canada (62%), Austrian Airlines (62%) or United Airlines (62%) 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, Aer Lingus or United Airlines 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.

£223+ Cheap Flights from Illinois to London Heathrow Airport

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 1 September 2026.

Wed 14/1019:15 -

1 stop14h 45m

Thu 22/1006:40 -

1 stop15h 30m

Deal found 31/8£520

Mon 5/1019:15 -

1 stop14h 45m

Wed 21/1021:05 -

2 stops25h 05m

Deal found 30/8£521

Fri 25/1219:15 -

2 stops31h 40m

Thu 31/1206:40 -

1 stop16h 05m

Deal found 28/8£522

Sat 17/1019:15 -

2 stops17h 35m

Sat 24/1015:35 -

2 stops32h 10m

Deal found 28/8£523

Sun 1/1120:10 -

1 stop19h 25m

Sun 8/1106:00 -

1 stop15h 30m

Deal found 27/8£523

Thu 8/1018:00 -

1 stop17h 45m

Tue 13/1018:45 -

1 stop27h 15m

Deal found 27/8£524

Mon 2/1119:15 -

2 stops15h 10m

Sun 22/1121:05 -

2 stops25h 40m

Deal found 28/8£525

Wed 21/1019:15 -

2 stops15h 45m

Fri 30/1010:20 -

1 stop12h 25m

Deal found 27/8£526

Sun 29/1119:15 -

2 stops15h 45m

Sat 12/1210:20 -

1 stop12h 25m

Deal found 1/9£526

Sat 17/1019:15 -

1 stop16h 25m

Tue 17/1106:40 -

1 stop16h 05m

Deal found 27/8£527

Thu 8/1019:15 -

2 stops18h 40m

Mon 12/1021:05 -

2 stops25h 05m

Deal found 27/8£528

Sun 27/919:25 -

1 stop10h 30m

Tue 6/1021:25 -

1 stop30h 00m

Deal found 1/9£529

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 1 September 2026.

Tue 27/1020:15 -

2 stops15h 10m

Sun 8/1121:05 -

2 stops25h 40m

Deal found 30/8£525

Mon 7/1210:55 -

1 stop19h 05m

Wed 9/1211:05 -

2 stops35h 26m

Deal found 31/8£581

Wed 27/106:30 -

1 stop18h 35m

Tue 2/211:45 -

2 stops14h 52m

Deal found 31/8£645

Wed 16/910:05 -

2 stops14h 40m

Fri 25/906:30 -

2 stops16h 17m

Deal found 31/8£645

Wed 23/918:45 -

1 stop12h 30m

Wed 30/910:45 -

1 stop12h 25m

Deal found 31/8£663

Mon 5/1021:30 -

Nonstop8h 25m

Mon 12/1017:15 -

1 stop28h 40m

Deal found 27/8£686

Thu 15/1017:00 -

Nonstop7h 50m

Sun 18/1009:45 -

Nonstop8h 45m

Deal found 29/8£740

Thu 15/1012:38 -

1 stop16h 37m

Thu 22/1011:10 -

1 stop12h 55m

Deal found 30/8£788

Thu 15/1018:48 -

2 stops35h 12m

Thu 22/1012:15 -

1 stop14h 10m

Deal found 30/8£794

Thu 15/1018:48 -

2 stops18h 07m

Thu 22/1006:10 -

2 stops20h 15m

Deal found 30/8£807

Fri 6/1119:15 -

1 stop14h 45m

Tue 10/1110:20 -

1 stop12h 25m

Deal found 28/8£527

Mon 11/117:20 -

1 stop11h 05m

Wed 13/106:50 -

2 stops15h 23m

Deal found 29/8£592

Sun 11/1019:15 -

1 stop17h 15m

Sun 18/1021:05 -

2 stops25h 05m

Deal found 27/8£588

Tue 2/213:00 -

2 stops12h 15m

Tue 9/210:00 -

2 stops18h 10m

Deal found 27/8£650

Mon 11/106:00 -

1 stop19h 50m

Wed 20/108:40 -

2 stops19h 23m

Deal found 30/8£656

Tue 13/1018:05 -

1 stop13h 10m

Tue 20/1011:15 -

1 stop12h 10m

Deal found 29/8£677

Wed 3/217:45 -

Nonstop8h 10m

Mon 8/213:45 -

1 stop32h 30m

Deal found 30/8£637

Wed 20/106:00 -

1 stop21h 00m

Tue 26/110:00 -

2 stops18h 03m

Deal found 31/8£653

Sun 27/921:40 -

Nonstop8h 00m

Fri 9/1013:45 -

1 stop14h 29m

Deal found 28/8£749

Wed 27/113:00 -

1 stop11h 50m

Sun 31/106:30 -

2 stops18h 07m

Deal found 30/8£685

Fri 13/1106:20 -

1 stop19h 30m

Wed 18/1106:30 -

2 stops15h 48m

Deal found 1/9£692

Wed 7/1021:30 -

Nonstop8h 25m

Thu 15/1006:50 -

1 stop11h 10m

Deal found 28/8£644

Tue 13/1012:13 -

1 stop12h 12m

Thu 29/1006:30 -

2 stops21h 06m

Deal found 29/8£654

Thu 15/1006:06 -

1 stop19h 09m

Thu 22/1006:30 -

2 stops22h 06m

Deal found 31/8£692

Mon 22/217:25 -

1 stop12h 15m

Sat 6/308:55 -

1 stop13h 30m

Deal found 29/8£706

Tue 17/1113:15 -

3 stops15h 35m

Tue 1/1212:15 -

2 stops15h 10m

Deal found 1/9£794

Wed 9/1215:45 -

Nonstop8h 10m

Sun 13/1207:30 -

1 stop13h 50m

Deal found 29/8£675

Wed 25/1114:31 -

1 stop11h 19m

Sat 5/1206:30 -

2 stops15h 54m

Deal found 31/8£675

Wed 7/1013:50 -

1 stop11h 25m

Wed 14/1008:40 -

2 stops19h 27m

Deal found 27/8£693

Thu 5/1112:13 -

2 stops12h 52m

Sun 8/1112:10 -

2 stops14h 11m

Deal found 31/8£931

Find flight deals from Illinois to Heathrow

Round-trip from	£520
One-way from	£223
Popular in	June
Cheapest in	February
Average price	£633
Good round-trip deal	£689 or less
Good one-way deal	£232 or less

Scandinavian Airlines
14/10-22/10
2 total stops
30h 15m total
Illinois to London

Search Deals

British Airways
3/12
1 total stop
18h 57m total
Illinois to London

Search Deals

Highest demand for flights based on searches. 23% potential increase in price (£141 potential increase over avg. return price).

Search Deals

Cheapest flight prices on average. 6% potential price decrease (£27 potential savings vs. average return price).

Search Deals

Average for round-trip flights in September 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

Cheapest return flight

ChicagoLondon

ORD Chicago O'Hare Intl - LHR London Heathrow

ORDLHR

Chicago O'Hare Intl

Tue 27/10

20:15-16:25

2 stops15h 10m

London Heathrow

Sun 8/11

21:05-16:45

2 stops25h 40m

£525

ChicagoLondon

ORD Chicago O'Hare Intl - LHR London Heathrow

ORDLHR

Chicago O'Hare Intl

Fri 6/11

19:15-16:00

1 stop14h 45m

London Heathrow

Tue 10/11

10:20-16:45

1 stop12h 25m

£527

PeoriaLondon

PIA Greater Peoria - LHR London Heathrow

PIALHR

Greater Peoria

Mon 7/12

10:55-12:00

1 stop19h 05m

London Heathrow

Wed 9/12

11:05-16:31

2 stops35h 26m

£581

ChicagoLondon

ORD Chicago O'Hare Intl - LHR London Heathrow

ORDLHR

Chicago O'Hare Intl

Sun 11/10

19:15-18:30

1 stop17h 15m

London Heathrow

Sun 18/10

21:05-16:10

2 stops25h 05m

£588

St. LouisLondon

STL Lambert-St Louis - LHR London Heathrow

STLLHR

Lambert-St Louis

Mon 11/1

17:20-10:25

1 stop11h 05m

London Heathrow

Wed 13/1

06:50-16:13

2 stops15h 23m

£592

ChicagoLondon

ORD Chicago O'Hare Intl - LHR London Heathrow

ORDLHR

Chicago O'Hare Intl

Wed 3/2

17:45-07:55

Nonstop8h 10m

London Heathrow

Mon 8/2

13:45-16:15

1 stop32h 30m

£637

ChicagoLondon

ORD Chicago O'Hare Intl - LHR London Heathrow

ORDLHR

Chicago O'Hare Intl

Wed 7/10

21:30-11:55

Nonstop8h 25m

London Heathrow

Thu 15/10

06:50-12:00

1 stop11h 10m

£644

St. LouisLondon

STL Lambert-St Louis - LHR London Heathrow

STLLHR

Lambert-St Louis

Wed 27/1

06:30-07:05

1 stop18h 35m

London Heathrow

Tue 2/2

11:45-20:37

2 stops14h 52m

£645

St. LouisLondon

STL Lambert-St Louis - LHR London Heathrow

STLLHR

Lambert-St Louis

Wed 16/9

10:05-06:45

2 stops14h 40m

London Heathrow

Fri 25/9

06:30-16:47

2 stops16h 17m

£645

ChicagoLondon

MDW Chicago Midway - LHR London Heathrow

MDWLHR

Chicago Midway

Tue 2/2

13:00-07:15

2 stops12h 15m

London Heathrow

Tue 9/2

10:00-22:10

2 stops18h 10m

£650

Flights are sorted by cheapest return flights first.

Deals found on 31/8

Showing 1-10 of 60 resultsSorted by cheapest first

...

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

STL-LHR

MDW-LHR

EVV-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

STL-LHR

MDW-LHR

EVV-LHR

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

Currently, January is the cheapest month in which you can book a flight from Illinois to London Heathrow Airport (average of £486). Flying from Illinois to London Heathrow Airport in June is currently the most expensive (average of £1,022). 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 Friday (54 on average). You will have fewer flight options on Wednesday, which is when the least amount of flights are scheduled (42 on average).

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 £546 and £780 in October.
The cheapest return price found within the last 5 days was £520 on Scandinavian Airlines (14 Oct–22 Oct).

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

The price you pay for your flight from Illinois to London Heathrow Airport may vary depending on when you book. For the best chance of a lower fare, look to book 58 days in advance of your trip. Fares are likely to increase a fortnight or so before your departure date.

Related info for your journey

How long is the flight from Illinois to London Heathrow Airport?
For as low as £525, Scandinavian Airlines can have you in London Heathrow Airport from Illinois in 15h 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 Lufthansa, with whom users have recently found tickets for as low as £278. However, be on the lookout for offers from British Airways and Iberia, 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 Air Canada (62%), Austrian Airlines (62%) or United Airlines (62%) 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 £1,340 for a flight from Illinois to London Heathrow Airport. The cheapest flight overall is £228 while the most popular route, (Chicago O'Hare Intl - London Heathrow) is currently priced at £395.
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, January is the cheapest month in which you can book a flight from Illinois to London Heathrow Airport (average of £486). Flying from Illinois to London Heathrow Airport in June is currently the most expensive (average of £1,022). 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
Icelandair	Cheapest£361	Average£557	FlexibilityNo cancel fee	On-time76%	Search Icelandair flights
American Airlines	Cheapest£382	Average£817	FlexibilityNo cancel fee	On-time71%	Search American Airlines flights
British Airways	Cheapest£419	Average£620	FlexibilityNo cancel fee	On-time70%	Search British Airways flights
Aer Lingus	Cheapest£455	Average£800	FlexibilityNo cancel fee	On-timeN/A	Search Aer Lingus flights
United Airlines	Cheapest£503	Average£861	FlexibilityNo cancel fee	On-time69%	Search United Airlines flights
Iberia	Cheapest£514	Average£690	FlexibilityNo cancel fee	On-time77%	Search Iberia flights
JetBlue	Cheapest£734	Average£874	FlexibilityNo cancel fee	On-time62%	Search JetBlue 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 £223

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 3/12. 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 1 September 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 1 September 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 1 September 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 1 September 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 1 September 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 1 September 2026.

Last-minute flights from Illinois to HeathrowDiscover last-minute flight deals from Illinois to Heathrow. Data last updated 1 September 2026 and is based on user searches.

Discover last-minute flight deals from Illinois to Heathrow. Data last updated 1 September 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 1 September 2026.

Search for one-way flight options from Illinois to Heathrow. Find affordable one-way fares based on user searches. Data last updated 1 September 2026.

Find flight deals from Illinois to Heathrow

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

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 1 September 2026.

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

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 1 September 2026.

The most flights from USIL to LHR are scheduled on a Friday (54 on average). You will have fewer flight options on Wednesday, which is when the least amount of flights are scheduled (42 on average).

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 £546 and £780 in October.The cheapest return price found within the last 5 days was £520 on Scandinavian Airlines (14 Oct–22 Oct).

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

The price you pay for your flight from Illinois to London Heathrow Airport may vary depending on when you book. For the best chance of a lower fare, look to book 58 days in advance of your trip. Fares are likely to increase a fortnight or so before your departure date.

Related info for your journey

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?

Browse thousands of different options on Cheapflights for your next trip

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Alternative routes for Illinois to Heathrow

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Search flights from Illinois to Heathrow by cabin class

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Other flights to Heathrow

Explore flights to Heathrow departing from other origins. Flights are based on user searches made on Cheapflights and were last updated on 1 September 2026.

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

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

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

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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 1 September 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 1 September 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 1 September 2026.

Last-minute flights from Illinois to Heathrow
Discover last-minute flight deals from Illinois to Heathrow. Data last updated 1 September 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 1 September 2026.

Illinois to London Heathrow Airport flights typically cost between £546 and £780 in October.
The cheapest return price found within the last 5 days was £520 on Scandinavian Airlines (14 Oct–22 Oct).