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

For as low as £564, Delta can have you in London Heathrow Airport from Illinois in 18h 05m. 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 £285. However, be on the lookout for offers from Iberia 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 £683 for a flight from Illinois to London Heathrow Airport. The cheapest flight overall is £233 while the most popular route, (Chicago O'Hare Intl - London Heathrow) is currently priced at £391.

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 Royal Jordanian (73%), Malaysia Airlines (68%) or Air Canada (66%) 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.

£228+ 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 26 September 2026.

Sun 4/1021:30 -

Nonstop8h 25m

Tue 13/1006:50 -

1 stop11h 10m

Deal found 23/9£543

Tue 3/1113:55 -

1 stop11h 15m

Fri 13/1109:00 -

2 stops16h 05m

Deal found 23/9£544

Tue 1/1221:50 -

Nonstop7h 45m

Tue 8/1215:40 -

Nonstop9h 05m

Deal found 22/9£545

Fri 16/1014:20 -

1 stop20h 05m

Fri 23/1008:40 -

1 stop13h 15m

Deal found 22/9£545

Sun 4/1013:29 -

1 stop10h 51m

Tue 13/1008:40 -

1 stop11h 35m

Deal found 23/9£546

Wed 21/1012:59 -

1 stop11h 36m

Wed 28/1011:10 -

1 stop13h 15m

Deal found 21/9£547

Wed 2/1213:55 -

1 stop11h 15m

Tue 8/1206:00 -

2 stops17h 43m

Deal found 21/9£548

Wed 25/1117:10 -

Nonstop7h 45m

Wed 2/1206:15 -

1 stop14h 40m

Deal found 21/9£548

Wed 4/1116:40 -

1 stop11h 15m

Tue 15/1206:20 -

1 stop15h 55m

Deal found 22/9£549

Tue 3/1110:15 -

2 stops14h 55m

Tue 10/1109:00 -

2 stops16h 58m

Deal found 21/9£550

Mon 2/1118:35 -

Nonstop8h 00m

Wed 11/1115:40 -

Nonstop9h 05m

Deal found 23/9£551

Mon 28/917:55 -

Nonstop7h 45m

Tue 6/1009:45 -

Nonstop8h 45m

Deal found 21/9£551

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 26 September 2026.

Tue 1/1206:00 -

1 stop18h 20m

Fri 11/1211:45 -

2 stops17h 12m

Deal found 22/9£557

Wed 3/207:05 -

1 stop18h 05m

Mon 8/211:05 -

1 stop31h 05m

Deal found 21/9£564

Sun 25/1005:00 -

1 stop10h 35m

Tue 3/1106:00 -

1 stop12h 40m

Deal found 25/9£656

Wed 14/1010:24 -

2 stops16h 56m

Thu 22/1007:05 -

2 stops15h 05m

Deal found 23/9£666

Sun 21/322:50 -

Nonstop7h 45m

Thu 25/315:40 -

Nonstop9h 05m

Deal found 23/9£687

Wed 17/316:00 -

1 stop10h 50m

Tue 23/306:20 -

2 stops21h 03m

Deal found 22/9£573

Thu 5/1115:45 -

Nonstop8h 10m

Tue 10/1109:00 -

1 stop13h 15m

Deal found 22/9£573

Thu 22/1013:55 -

1 stop11h 15m

Thu 29/1006:20 -

2 stops15h 12m

Deal found 22/9£595

Sat 26/1219:15 -

1 stop20h 25m

Wed 6/119:30 -

1 stop27h 15m

Deal found 21/9£700

Wed 25/1106:25 -

1 stop23h 35m

Fri 4/1209:00 -

2 stops20h 09m

Deal found 22/9£652

Wed 17/317:00 -

1 stop12h 30m

Wed 31/308:40 -

1 stop11h 35m

Deal found 21/9£598

Wed 24/316:45 -

Nonstop8h 10m

Sat 3/407:25 -

1 stop16h 50m

Deal found 21/9£654

Mon 8/306:01 -

1 stop20h 59m

Sun 14/308:55 -

1 stop18h 28m

Deal found 22/9£617

Thu 26/1108:15 -

2 stops19h 05m

Fri 4/1207:30 -

2 stops16h 28m

Deal found 22/9£662

Thu 25/307:00 -

2 stops20h 30m

Tue 30/308:45 -

2 stops20h 13m

Deal found 22/9£666

Mon 22/306:01 -

1 stop20h 49m

Wed 31/311:30 -

2 stops16h 53m

Deal found 22/9£667

Thu 25/310:56 -

2 stops16h 34m

Thu 1/408:45 -

2 stops18h 31m

Deal found 22/9£670

Mon 22/316:00 -

2 stops13h 40m

Tue 30/315:15 -

1 stop13h 08m

Deal found 22/9£689

Tue 23/315:30 -

1 stop11h 25m

Thu 1/411:05 -

1 stop11h 26m

Deal found 22/9£689

Mon 9/1116:28 -

1 stop13h 12m

Mon 16/1106:20 -

2 stops22h 11m

Deal found 25/9£711

Wed 24/307:00 -

1 stop17h 55m

Sun 28/312:05 -

2 stops16h 53m

Deal found 22/9£692

Mon 22/317:40 -

1 stop13h 20m

Sun 28/312:05 -

2 stops16h 53m

Deal found 22/9£692

Wed 17/307:00 -

1 stop17h 55m

Tue 23/309:00 -

2 stops19h 08m

Deal found 26/9£697

Sat 26/1221:47 -

1 stop29h 23m

Tue 29/1206:35 -

1 stop17h 50m

Deal found 21/9£704

Mon 22/315:30 -

1 stop15h 30m

Mon 29/317:50 -

2 stops28h 41m

Deal found 25/9£709

Fri 6/1115:45 -

Nonstop8h 10m

Tue 10/1109:00 -

1 stop13h 15m

Deal found 25/9£715

Find flight deals from Illinois to Heathrow

Round-trip from	£543
One-way from	£228
Popular in	June
Cheapest in	February
Average price	£684
Good round-trip deal	£784 or less
Good one-way deal	£291 or less

TAP AIR PORTUGAL
1/11-12/11
2 total stops
40h 55m total
Illinois to London

Search Deals

Icelandair
27/10-31/12
1 total stop
10h 20m total
Illinois to London

Search Deals

Highest demand for flights based on searches. 22% potential increase in price (£140 potential increase over avg. return price).

Search Deals

Cheapest flight prices on average. 6% potential price decrease (£28 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

Fastest return journey

ChicagoLondon

ORD Chicago O'Hare Intl - LHR London Heathrow

ORDLHR

Chicago O'Hare Intl

Wed 30/12

17:45-07:55

Nonstop8h 10m

London Heathrow

Wed 31/12

00:00-17:00

Nonstop0h 00m

£246

ChicagoLondon

ORD Chicago O'Hare Intl - LHR London Heathrow

ORDLHR

Chicago O'Hare Intl

Tue 29/12

17:45-07:55

Nonstop8h 10m

London Heathrow

Wed 31/12

00:00-17:00

Nonstop0h 00m

£246

ChicagoLondon

ORD Chicago O'Hare Intl - LHR London Heathrow

ORDLHR

Chicago O'Hare Intl

Mon 22/3

16:45-05:55

Nonstop8h 10m

London Heathrow

Wed 31/12

00:00-17:00

Nonstop0h 00m

£246

ChicagoLondon

ORD Chicago O'Hare Intl - LHR London Heathrow

ORDLHR

Chicago O'Hare Intl

Wed 24/3

15:40-11:50

1 stop15h 10m

London Heathrow

Wed 31/12

00:00-17:00

Nonstop0h 00m

£246

BloomingtonLondon

BMI Bloomington-Normal - LHR London Heathrow

BMILHR

Bloomington-Normal

Mon 22/3

12:00-11:40

1 stop18h 40m

London Heathrow

Wed 31/12

00:00-17:00

Nonstop0h 00m

£251

BloomingtonLondon

BMI Bloomington-Normal - LHR London Heathrow

BMILHR

Bloomington-Normal

Mon 22/3

16:00-07:50

1 stop10h 50m

London Heathrow

Wed 31/12

00:00-17:00

Nonstop0h 00m

£252

BloomingtonLondon

BMI Bloomington-Normal - LHR London Heathrow

BMILHR

Bloomington-Normal

Wed 24/3

16:00-09:00

1 stop12h 00m

London Heathrow

Wed 31/12

00:00-17:00

Nonstop0h 00m

£252

BloomingtonLondon

BMI Bloomington-Normal - LHR London Heathrow

BMILHR

Bloomington-Normal

Tue 23/3

06:01-08:05

2 stops21h 04m

London Heathrow

Wed 31/12

00:00-17:00

Nonstop0h 00m

£252

BloomingtonLondon

BMI Bloomington-Normal - LHR London Heathrow

BMILHR

Bloomington-Normal

Sun 21/3

16:00-07:50

1 stop10h 50m

London Heathrow

Wed 31/12

00:00-17:00

Nonstop0h 00m

£252

PeoriaLondon

PIA Greater Peoria - LHR London Heathrow

PIALHR

Greater Peoria

Mon 22/3

05:45-06:40

2 stops19h 55m

London Heathrow

Wed 31/12

00:00-17:00

Nonstop0h 00m

£267

Flights are sorted by cheapest return flights first.

Deals found on 25/9

Showing 1-10 of 49 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

BMI-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

BMI-LHR

PIA-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 £478). Flying from Illinois to London Heathrow Airport in June is currently the most expensive (average of £1,044). 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 Wednesday (49 on average). You will have fewer flight options on Tuesday, 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 typical for this route at the moment.

Illinois to London Heathrow Airport flights typically cost between £530 and £718 in November.
The cheapest return price found within the last 5 days was £543 on TAP AIR PORTUGAL (1 Nov–12 Nov).

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 65 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 £564, Delta can have you in London Heathrow Airport from Illinois in 18h 05m. 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 £285. However, be on the lookout for offers from Iberia 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 Royal Jordanian (73%), Malaysia Airlines (68%) or Air Canada (66%) 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 £683 for a flight from Illinois to London Heathrow Airport. The cheapest flight overall is £233 while the most popular route, (Chicago O'Hare Intl - London Heathrow) is currently priced at £391.
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 £478). Flying from Illinois to London Heathrow Airport in June is currently the most expensive (average of £1,044). 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

Hounslow

Luton

Milton Keynes

Gatwick

Wembley

Slough

Ilford

Hayes

Croydon

Northampton

Colchester

Eastbourne

Enfield

Brentford

Southend-on-Sea

Barnet

Southall

Watford

Stratford-upon-Avon

Kingston upon Thames

Browse thousands of different options on Cheapflights for your next trip

Alternative routes

Complete your trip

Direct flights to England

Flights by cabin class

Heathrow flight routes

Other flight options

Popular flights

Top destinations

Alternative routes for Illinois to Heathrow

John F Kennedy Intl to Heathrow flights

Newark to Heathrow flights

John F Kennedy Intl to Stansted flights

LaGuardia to Heathrow flights

Newark to Gatwick flights

John F Kennedy Intl to London City flights

Dulles Intl to Heathrow flights

John F Kennedy Intl to Gatwick flights

Boston to Heathrow flights

LaGuardia to Gatwick flights

Baltimore to Heathrow flights

Los Angeles to Heathrow flights

O'Hare Intl to Heathrow flights

Dallas/Fort Worth to Heathrow flights

San Francisco to Heathrow flights

Newark to London City flights

Newark to Stansted flights

Dulles Intl to Gatwick flights

Newark to Luton flights

Reagan-National to Heathrow flights

Atlanta to Heathrow flights

Boston to Gatwick flights

Boston to London City flights

Seattle to Heathrow flights

Orlando to Heathrow flights

Dulles Intl to London City flights

Boston to Stansted flights

Philadelphia to Heathrow flights

Miami to Heathrow flights

Los Angeles to Gatwick flights

San Francisco to Gatwick flights

Denver to Heathrow flights

Los Angeles to Stansted flights

Hobby to Heathrow flights

Los Angeles to London City flights

O'Hare Intl to Gatwick flights

O'Hare Intl to Stansted flights

O'Hare Intl to London City flights

Dallas/Fort Worth to Gatwick flights

Orlando to Gatwick flights

Baltimore to Gatwick flights

Dulles Intl to Luton flights

San Francisco to London City flights

Boston to Luton flights

Austin to Heathrow flights

Reagan-National to Gatwick flights

San Francisco to Stansted flights

George Bush Intcntl to Heathrow flights

Top 7 airlines flying from Illinois to Heathrow

Airline	Cheapest	Average	Flexibility	On-time
Icelandair	Cheapest£370	Average£570	FlexibilityNo cancel fee	On-time76%	Search Icelandair flights
British Airways	Cheapest£460	Average£738	FlexibilityNo cancel fee	On-time70%	Search British Airways flights
Aer Lingus	Cheapest£466	Average£819	FlexibilityNo cancel fee	On-timeN/A	Search Aer Lingus flights
American Airlines	Cheapest£496	Average£865	FlexibilityNo cancel fee	On-time71%	Search American Airlines flights
United Airlines	Cheapest£515	Average£926	FlexibilityNo cancel fee	On-time69%	Search United Airlines flights
Iberia	Cheapest£526	Average£706	FlexibilityNo cancel fee	On-time77%	Search Iberia flights
JetBlue	Cheapest£751	Average£895	FlexibilityNo cancel fee	On-time62%	Search JetBlue flights

Fly with Cheapflights

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.

100% Free

Cheapflights is completely free to use, so you can start saving the moment you arrive.

Book with Flexibility

Our users can plan ahead with confidence and find flights with no change fees

Travel Smart

Millions of people come to us for their flight needs every year. We help make travel planning easy by providing useful insights and data-driven graphs that can inform your decisions.

Cheap flights from Illinois to London Heathrow Airport from £228

This is the cheapest retur flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 27/10. 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 26 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 26 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 26 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 26 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 26 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 26 September 2026.

Last-minute flights from Illinois to HeathrowDiscover last-minute flight deals from Illinois to Heathrow. Data last updated 26 September 2026 and is based on user searches.

Discover last-minute flight deals from Illinois to Heathrow. Data last updated 26 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 26 September 2026.

Search for one-way flight options from Illinois to Heathrow. Find affordable one-way fares based on user searches. Data last updated 26 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 26 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 26 September 2026.

The most flights from USIL to LHR are scheduled on a Wednesday (49 on average). You will have fewer flight options on Tuesday, 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 typical for this route at the moment.

Illinois to London Heathrow Airport flights typically cost between £530 and £718 in November.The cheapest return price found within the last 5 days was £543 on TAP AIR PORTUGAL (1 Nov–12 Nov).

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 65 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

Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.

Alternative routes for Illinois to Heathrow

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

Complete your trip

Complete your trip to Heathrow by adding a car hire and/or hotel booking to your travel itinerary.

Direct flights to England

Book a non-stop flight to one of these other cities located in England.

Search flights from Illinois to Heathrow by cabin class

Find flights from Illinois to Heathrow, based on your preferred cabin class, be it economy, premium economy, business, or first class.

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 26 September 2026.

Illinois and Heathrow flights

Browse other Illinois and Heathrow flight options. Last updated on 26 September 2026.

Popular flight searches

Check out other popular destinations found by fellow travellers in 2026

Illinois to Heathrow flights

Consider these flights travelling from Illinois to Heathrow.

Top 7 airlines flying from Illinois to Heathrow

Fly with Cheapflights

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

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

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?

100% Free

Book with Flexibility

Travel Smart

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 26 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 26 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 26 September 2026.

Last-minute flights from Illinois to Heathrow
Discover last-minute flight deals from Illinois to Heathrow. Data last updated 26 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 26 September 2026.

Illinois to London Heathrow Airport flights typically cost between £530 and £718 in November.
The cheapest return price found within the last 5 days was £543 on TAP AIR PORTUGAL (1 Nov–12 Nov).