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

The cheapest airline one-way is Icelandair, with whom users have recently found tickets for as low as £202. However, be on the lookout for offers from TAP AIR PORTUGAL and JetBlue, 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 cheapest flights from Illinois to London Heathrow Airport?

On average you can expect to pay £3,081 for a flight from Illinois to London Heathrow Airport. The cheapest flight overall is £290 while the most popular route, (Chicago O'Hare Intl - London Heathrow) is currently priced at £398.

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 (88%), Gulf Air (82%) or Malaysia Airlines (79%) 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 American Airlines, Finnair or British Airways when booking your flight. These represent the most popular airlines when flying from Illinois to London Heathrow Airport.

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

To save on the cost of your flight from Illinois to London Heathrow Airport, book at least 60 days before your planned departure. Booking around this time can save you about 7% on the cost of this flight compared to booking a flight leaving this week. We have found prices from £535 if you need a flight within two weeks. For flights within the next 72 hours, you can find tickets from as low as £539.

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

February is one of the best times of the year to fly to London Heathrow Airport from Illinois. Prices for February average £565 per person but you can even find prices for as low as £357. The most expensive prices can be found in the month of June. Opting for a February flight can save you 32% on your journey compared to booking in June

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.

£202+ Flights from Illinois to London Heathrow Airport

Cheap flight deals from Illinois to Heathrow

Round-trip from	£452
One-way from	£202
Popular in	June
Cheapest in	February
Average price	£507
Good round-trip deal	£512 or less
Good one-way deal	£309 or less

Icelandair
6/9-6/10
2 total stops
21h 40m total
Illinois to London

Search Deals

Icelandair
4/5
1 total stop
31h 40m total
Illinois to London

Search Deals

Highest demand for flights based on searches. 17% potential increase in price (£88 potential increase over avg. return price).

Search Deals

Cheapest flight prices on average. 3% potential price decrease (£14 potential savings vs. average return price).

Search Deals

Average for round-trip flights in April 2025

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

Find flight deals from Illinois to Heathrow

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 18 April 2025.

Sat 6/919:25ORD - LHR

1 stop10h 30mIcelandair

Mon 6/1013:05LHR - ORD

1 stop11h 10mIcelandair

Deal found 17/4£452

Sat 27/921:12ORD - LHR

2 stops17h 48mMultiple Airlines

Sat 4/1020:05LHR - ORD

1 stop22h 05mMultiple Airlines

Deal found 17/4£452

Tue 14/1019:15ORD - LHR

1 stop16h 25mScandinavian Airlines

Mon 27/1006:40LHR - ORD

1 stop16h 05mScandinavian Airlines

Deal found 18/4£454

Mon 4/816:00ORD - LHR

1 stop10h 35mAir Canada

Fri 15/809:30LHR - ORD

1 stop11h 21mAir Canada

Deal found 17/4£455

Tue 5/815:16ORD - LHR

1 stop10h 34mIberia

Wed 20/814:25LHR - ORD

Nonstop8h 35mIberia

Deal found 17/4£458

Tue 6/517:40ORD - LHR

Nonstop7h 40mBritish Airways

Tue 13/509:15LHR - ORD

Nonstop8h 30mBritish Airways

Deal found 17/4£459

Wed 7/518:35ORD - LHR

1 stop12h 25mSWISS

Wed 14/520:05LHR - ORD

1 stop25h 50mSWISS

Deal found 16/4£461

Mon 5/521:15ORD - LHR

1 stop10h 10mAer Lingus

Wed 7/507:40LHR - ORD

1 stop12h 20mAer Lingus

Deal found 17/4£467

Sat 3/510:50ORD - LHR

1 stop13h 40mJetBlue

Thu 8/511:55LHR - ORD

1 stop15h 59mJetBlue

Deal found 17/4£489

Tue 26/822:35ORD - LHR

Nonstop7h 40mAmerican Airlines

Tue 16/907:40LHR - ORD

1 stop14h 05mAmerican Airlines

Deal found 18/4£490

Sun 3/817:45ORD - LHR

Nonstop7h 35mFinnair

Thu 21/810:20LHR - ORD

1 stop13h 30mFinnair

Deal found 18/4£491

Tue 6/516:05ORD - LHR

Nonstop8h 15mUnited Airlines

Tue 13/512:10LHR - ORD

1 stop33h 45mUnited Airlines

Deal found 17/4£500

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 18 April 2025.

Sat 6/919:25ORD - LHR

1 stop10h 30mIcelandair

Mon 6/1013:05LHR - ORD

1 stop11h 10mIcelandair

Deal found 17/4£452

Sat 27/921:12ORD - LHR

2 stops17h 48mMultiple Airlines

Sat 4/1020:05LHR - ORD

1 stop22h 05mMultiple Airlines

Deal found 17/4£452

Mon 29/919:15ORD - LHR

1 stop16h 25mScandinavian Airlines

Tue 14/1010:20LHR - ORD

1 stop11h 50mScandinavian Airlines

Deal found 17/4£454

Mon 4/816:00ORD - LHR

1 stop10h 35mAir Canada

Fri 15/809:30LHR - ORD

1 stop11h 21mAir Canada

Deal found 17/4£455

Tue 5/815:16ORD - LHR

1 stop10h 34mIberia

Wed 20/814:25LHR - ORD

Nonstop8h 35mIberia

Deal found 17/4£458

Tue 6/517:40ORD - LHR

Nonstop7h 40mBritish Airways

Tue 13/509:15LHR - ORD

Nonstop8h 30mBritish Airways

Deal found 17/4£459

Wed 7/518:35ORD - LHR

1 stop12h 25mSWISS

Wed 14/520:05LHR - ORD

1 stop25h 50mSWISS

Deal found 16/4£461

Mon 5/521:15ORD - LHR

1 stop10h 10mAer Lingus

Wed 7/507:40LHR - ORD

1 stop12h 20mAer Lingus

Deal found 17/4£467

Sat 3/510:50ORD - LHR

1 stop13h 40mJetBlue

Thu 8/511:55LHR - ORD

1 stop15h 59mJetBlue

Deal found 17/4£489

Tue 13/518:05ORD - LHR

Nonstop8h 15mLufthansa

Wed 21/514:10LHR - ORD

Nonstop9h 05mLufthansa

Deal found 17/4£489

Tue 26/822:35ORD - LHR

Nonstop7h 40mAmerican Airlines

Tue 16/907:40LHR - ORD

1 stop14h 05mAmerican Airlines

Deal found 18/4£490

Sun 3/817:45ORD - LHR

Nonstop7h 35mFinnair

Thu 21/810:20LHR - ORD

1 stop13h 30mFinnair

Deal found 18/4£491

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 18 April 2025.

Tue 5/822:35ORD - LHR

Nonstop7h 40mIberia

Wed 20/814:25LHR - ORD

Nonstop8h 35mIberia

Deal found 17/4£458

Tue 6/517:40ORD - LHR

Nonstop7h 40mBritish Airways

Tue 13/509:15LHR - ORD

Nonstop8h 30mBritish Airways

Deal found 17/4£459

Tue 13/516:05ORD - LHR

Nonstop8h 15mLufthansa

Wed 21/511:05LHR - ORD

Nonstop9h 05mLufthansa

Deal found 17/4£489

Mon 5/516:55ORD - LHR

Nonstop7h 55mFinnair

Wed 14/511:05LHR - ORD

Nonstop8h 45mFinnair

Deal found 17/4£507

Tue 6/518:05ORD - LHR

Nonstop8h 15mUnited Airlines

Tue 13/514:10LHR - ORD

Nonstop9h 05mUnited Airlines

Deal found 17/4£513

Sat 27/917:45ORD - LHR

Nonstop7h 35mAmerican Airlines

Sat 4/1009:15LHR - ORD

Nonstop8h 35mAmerican Airlines

Deal found 17/4£588

Mon 1/916:00ORD - LHR

Nonstop8h 20mBrussels Airlines

Wed 10/914:10LHR - ORD

Nonstop9h 10mBrussels Airlines

Deal found 17/4£658

Wed 7/522:25ORD - LHR

Nonstop7h 50mAlaska Airlines

Fri 16/513:10LHR - ORD

Nonstop8h 45mAlaska Airlines

Deal found 16/4£664

Wed 30/418:05ORD - LHR

Nonstop8h 15mAustrian Airlines

Sun 4/511:05LHR - ORD

Nonstop9h 05mAustrian Airlines

Deal found 17/4£704

Last-minute flights from Illinois to Heathrow
Discover last-minute flight deals from Illinois to Heathrow. Data last updated 18 April 2025 and is based on user searches.

Thu 17/422:20ORD - LHR

Nonstop7h 55mIberia

Wed 23/412:15LHR - ORD

Nonstop8h 30mIberia

Deal found 17/4£462

Tue 22/415:35ORD - LHR

1 stop12h 25mAir Canada

Tue 29/409:30LHR - ORD

1 stop11h 25mAir Canada

Deal found 17/4£463

Wed 23/414:35ORD - LHR

1 stop15h 45mMultiple Airlines

Mon 28/417:10LHR - ORD

1 stop28h 45mMultiple Airlines

Deal found 17/4£502

Wed 23/412:15ORD - LHR

1 stop18h 55mDelta

Thu 1/506:30LHR - ORD

2 stops15h 38mDelta

Deal found 17/4£516

Thu 24/413:26ORD - LHR

1 stop14h 04mJetBlue

Thu 1/511:55LHR - ORD

1 stop16h 27mJetBlue

Deal found 17/4£500

Fri 25/418:35ORD - LHR

1 stop17h 15mSWISS

Mon 28/408:40LHR - ORD

1 stop33h 30mSWISS

Deal found 17/4£504

Fri 25/422:15ORD - LHR

1 stop16h 05mIcelandair

Mon 28/421:25LHR - ORD

1 stop26h 50mIcelandair

Deal found 17/4£520

Sun 27/417:05ORD - LHR

1 stop9h 50mKLM

Wed 7/509:55LHR - ORD

1 stop10h 45mKLM

Deal found 17/4£507

Mon 28/415:45ORD - LHR

1 stop11h 20mAer Lingus

Thu 1/507:40LHR - ORD

1 stop12h 20mAer Lingus

Deal found 17/4£493

Mon 28/421:30ORD - LHR

1 stop18h 40mFinnair

Fri 9/507:30LHR - ORD

1 stop16h 20mFinnair

Deal found 17/4£498

Mon 28/415:35ORD - LHR

1 stop12h 25mUnited Airlines

Wed 7/512:10LHR - ORD

1 stop33h 45mUnited Airlines

Deal found 17/4£501

Mon 28/411:36ORD - LHR

1 stop15h 34mBritish Airways

Wed 7/506:15LHR - ORD

1 stop14h 00mBritish Airways

Deal found 17/4£505

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 18 April 2025.

Sun 4/522:15ORD - LHR

1 stop31h 40mIcelandair

Deal found 17/4£202

Fri 18/718:00ORD - LHR

1 stop18h 50mTAP AIR PORTUGAL

Deal found 18/4£209

Sun 4/519:33ORD - LHR

3 stops34h 22mMultiple Airlines

Deal found 17/4£211

Thu 2/1013:35ORD - LHR

1 stop13h 55mJetBlue

Deal found 16/4£260

Tue 13/509:34MDW - LHR

3 stops28h 46mMultiple Airlines

Deal found 17/4£264

Mon 8/919:15ORD - LHR

1 stop16h 25mScandinavian Airlines

Deal found 17/4£278

Mon 12/515:45ORD - LHR

1 stop11h 20mAer Lingus

Deal found 18/4£291

Tue 13/521:30ORD - LHR

1 stop18h 40mFinnair

Deal found 18/4£298

Sun 20/721:15ORD - LHR

Nonstop7h 40mIberia

Deal found 17/4£299

Sat 10/520:25ORD - LHR

1 stop31h 10mAir Canada

Deal found 17/4£302

Mon 28/416:55ORD - LHR

Nonstop7h 55mBritish Airways

Deal found 17/4£306

Mon 28/412:48MDW - LHR

1 stop11h 57mVirgin Atlantic

Deal found 17/4£309

Cheapflights Fare Finder

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

Fly from

Fly to

Route

Depart

Return

Price

ChicagoLondon

ORD - LHR

ORDLHR

Chicago O'Hare Intl

Sat 6/9

19:25-11:55

1 stop10h 30m

London Heathrow

Mon 6/10

13:05-18:15

1 stop11h 10m

£452

ChicagoLondon

ORD - LHR

ORDLHR

Chicago O'Hare Intl

Sat 27/9

21:12-21:00

2 stops17h 48m

London Heathrow

Sat 4/10

20:05-12:10

1 stop22h 05m

£452

ChicagoLondon

ORD - LHR

ORDLHR

Chicago O'Hare Intl

Mon 29/9

19:15-17:40

1 stop16h 25m

London Heathrow

Tue 14/10

10:20-16:10

1 stop11h 50m

£454

ChicagoLondon

ORD - LHR

ORDLHR

Chicago O'Hare Intl

Mon 4/8

16:00-08:35

1 stop10h 35m

London Heathrow

Fri 15/8

09:30-14:51

1 stop11h 21m

£455

ChicagoLondon

ORD - LHR

ORDLHR

Chicago O'Hare Intl

Tue 5/8

15:16-07:50

1 stop10h 34m

London Heathrow

Wed 20/8

14:25-17:00

Nonstop8h 35m

£458

ChicagoLondon

ORD - LHR

ORDLHR

Chicago O'Hare Intl

Tue 6/5

17:40-07:20

Nonstop7h 40m

London Heathrow

Tue 13/5

09:15-11:45

Nonstop8h 30m

£459

ChicagoLondon

ORD - LHR

ORDLHR

Chicago O'Hare Intl

Wed 7/5

18:35-13:00

1 stop12h 25m

London Heathrow

Wed 14/5

20:05-15:55

1 stop25h 50m

£461

ChicagoLondon

ORD - LHR

ORDLHR

Chicago O'Hare Intl

Mon 5/5

21:15-13:25

1 stop10h 10m

London Heathrow

Wed 7/5

07:40-14:00

1 stop12h 20m

£467

ChicagoLondon

ORD - LHR

ORDLHR

Chicago O'Hare Intl

Sat 3/5

10:50-06:30

1 stop13h 40m

London Heathrow

Sat 10/5

08:15-21:54

1 stop19h 39m

£489

ChicagoLondon

ORD - LHR

ORDLHR

Chicago O'Hare Intl

Tue 13/5

18:05-08:20

Nonstop8h 15m

London Heathrow

Wed 21/5

14:10-17:15

Nonstop9h 05m

£489

Flights are sorted by cheapest return flights first.

Deals found on 17/4

Showing 1-10 of 56 results

...

Best time to book a flight from Illinois to Heathrow

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

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

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 £112). Flying from Illinois to London Heathrow Airport in August is currently the most expensive (average of £164). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

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

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

Weekly flight availability from Illinois to London Heathrow Airport

The most flights from USIL to LHR are scheduled on a Monday (57 on average). You will have fewer flight options on Sunday, which is when the least amount of flights are scheduled (49 on average).

Rainfall in Heathrow by month

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.

Temperature in Heathrow by month

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).

Reviews of airlines servicing Heathrow

To help decide which airline to fly from Illinois to London, see what other customers have to say about Delta, KLM and Finnair. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.

Delta

8.0

Very Good

7,917 reviews

Check prices

Reviews

1 / 20

10.0

Excellent

Aaron,Oct 2024

LAX - LHR

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.

Delta

8.0

Very Good

7,917 reviews

Delta

8.0

Very Good

7,917 reviews

Check prices

Reviews

1 / 20

10.0

Excellent

Aaron,Oct 2024

LAX - LHR

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.

KLM

7.8

Good

1,329 reviews

Delta

8.0

Very Good

7,917 reviews

Check prices

Reviews

1 / 20

10.0

Excellent

Aaron,Oct 2024

LAX - LHR

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.

Finnair

7.6

Good

1,269 reviews

Delta

8.0

Very Good

7,917 reviews

Check prices

Reviews

1 / 20

10.0

Excellent

Aaron,Oct 2024

LAX - LHR

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.

Air France

7.5

Good

1,435 reviews

Delta

8.0

Very Good

7,917 reviews

Check prices

Reviews

1 / 20

10.0

Excellent

Aaron,Oct 2024

LAX - LHR

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.

SWISS

7.5

Good

1,581 reviews

Delta

8.0

Very Good

7,917 reviews

Check prices

Reviews

1 / 20

10.0

Excellent

Aaron,Oct 2024

LAX - LHR

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.

Related info for your journey

What are the cheapest airlines to fly from Illinois to London Heathrow Airport one-way?
The cheapest airline one-way is Icelandair, with whom users have recently found tickets for as low as £202. However, be on the lookout for offers from TAP AIR PORTUGAL and JetBlue, 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 (88%), Gulf Air (82%) or Malaysia Airlines (79%) 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 £3,081 for a flight from Illinois to London Heathrow Airport. The cheapest flight overall is £290 while the most popular route, (Chicago O'Hare Intl - London Heathrow) is currently priced at £398.
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 £112). Flying from Illinois to London Heathrow Airport in August is currently the most expensive (average of £164). 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

Deal

Milton Keynes

Gatwick

Luton

Slough

Croydon

Eastbourne

Wembley

Northampton

Hayes

Crawley

Southend-on-Sea

Maidstone

Swindon

Ipswich

Southall

Ilford

Winchester

Folkestone

Browse thousands of different options on Cheapflights for your next trip

Top 6 airlines flying from Illinois to Heathrow

Airline	Cheapest	Average	Flexibility	On-time
Finnair	Cheapest£361	Average£700	FlexibilityNo cancel fee	On-time76%	Search Finnair flights
American Airlines	Cheapest£387	Average£771	FlexibilityNo cancel fee	On-time71%	Search American Airlines flights
Iberia	Cheapest£452	Average£613	FlexibilityNo cancel fee	On-time77%	Search Iberia flights
British Airways	Cheapest£482	Average£635	FlexibilityNo cancel fee	On-time70%	Search British Airways flights
Lufthansa	Cheapest£491	Average£1,023	FlexibilityNo cancel fee	On-time76%	Search Lufthansa flights
United Airlines	Cheapest£503	Average£692	FlexibilityNo cancel fee	On-time69%	Search United Airlines 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.

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Cheap flights from Illinois to London Heathrow Airport from £202

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 4/5. Fares are subject to change and may not be available on all flights or dates of travel.

Cheap flight deals from Illinois to Heathrow

Keep the following information in mind while searching for Illinois to Heathrow flight deals. Data was last updated 18 April 2025.

Round-trip from

One-way from

Popular in

Cheapest in

Average price

Good round-trip deal

Good one-way deal

Find 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 18 April 2025.

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 18 April 2025.

Cheapflights Fare Finder

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

Best time to book a flight from Illinois to Heathrow

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

Cheapflights Insights

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

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

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

Find hourly flight availability from Illinois to Heathrow. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated 18 April 2025.

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 18 April 2025.

Rainfall in Heathrow by month

Plan your trip to Heathrow by taking into account the average rainfall totals by month.

Temperature in Heathrow by month

Plan your trip to Heathrow by taking into account the average temperature totals by month.

Reviews of airlines servicing Heathrow

To help decide which airline to fly from Illinois to London, see what other customers have to say about Delta, KLM and Finnair. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.

Related info for your journey

Find useful and relevant information for your journey from Illinois to Heathrow. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

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?

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Top 6 airlines flying from Illinois to Heathrow

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Cheapest flights from Illinois to Heathrow
Explore the most affordable flight options available from Illinois to Heathrow. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 18 April 2025.