What are the cheapest airlines to fly from United Kingdom to Illinois one-way?

$450 is the cheapest one-way deal found within the past few days, from WestJet. You may also be able to find cheap deals on Air Transat and Icelandair, with prices starting from $493 and $504, respectively.

How far in advance should I book a flight from United Kingdom to Illinois?

To save up to 19% on this flight, we recommend booking at least 45 days prior to travel. The price may fluctuate and will likely increase closer to your departure date. Users on Cheapflights have found tickets from United Kingdom to Illinois from $683 1-2 weeks out and tickets from $812 for flights departing within the next 72 hours.

What is the cheapest month to fly from United Kingdom to Illinois?

February can be a great time to fly to Illinois from United Kingdom with a flight ticket averaging about $710. Cheapflights users have found deals in the month of February for as cheap as $425. The most expensive prices can be found in the month of August.

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

Yes. In addition to deals on United Kingdom to Illinois flights, Cheapflights offers vacation packages that include both flights and hotel.

How can I find direct flights from United Kingdom to Illinois?

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

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

Yes. Cheapflights offers flight deals from United Kingdom 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.

$549+ Flights from the United Kingdom to Illinois

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Cheap flight deals from United Kingdom to Illinois

Most accurate provider	FlightHub 3 stars
Most trusted provider	FlightHub 3 stars
Round-trip from	$527 (Lufthansa)
One-way from	$345 (Kiwi.com)
Popular in	August
Cheapest in	February
Average price	$579
Good round-trip deal	$640 or less
Good one-way deal	$646 or less

Provider with most accurate pricing for London (LON)-Chicago (CHI) flight deals.

Search Deals

Provider most trusted by Cheapflights users for London (LON)-Chicago (CHI) flights.

Search Deals

From United Kingdom to Illinois

Search Deals

One-way flight from United Kingdom to Illinois

Search Deals

Highest demand for flights based on searches. 12% potential increase in price ($98 potential increase over avg. RT price).

Search Deals

Cheapest flight prices on average. 2% potential price decrease ($17 potential savings vs. average RT price).

Search Deals

Average for round-trip flights in February 2025

Search Deals

Price to beat on a round-trip flight from United Kingdom to Illinois.

Search Deals

Price to beat on a one-way flight from United Kingdom to Illinois.

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Find flight deals from United Kingdom to Illinois

Cheapest flights from United Kingdom to Illinois
Explore the most affordable flight options available from United Kingdom to Illinois. Find the lowest fares from popular airlines and budget airlines, with prices last updated on February 20, 2025.

Wed 4/236:00 amLHR - ORD

1 stop12h 10mMultiple Airlines

Tue 4/294:05 pmORD - LHR

Nonstop8h 15mMultiple Airlines

Deal found 2/20

$527

Fri 3/77:40 amLHR - ORD

1 stop12h 30mUnited Airlines

Tue 3/182:16 pmORD - LHR

1 stop10h 39mUnited Airlines

Deal found 2/20

$528

Tue 2/258:40 pmLHR - ORD

1 stop26h 40mIcelandair

Mon 3/36:30 pmORD - LHR

1 stop19h 00mIcelandair

Deal found 2/20

$531

Thu 3/62:00 pmLGW - ORD

1 stop15h 28mMultiple Airlines

Tue 3/259:01 pmORD - LGW

2 stops30h 04mMultiple Airlines

Deal found 2/20

$532

Fri 2/216:00 amLHR - ORD

1 stop15h 30mTAP AIR PORTUGAL

Fri 2/288:20 pmORD - LHR

1 stop16h 35mTAP AIR PORTUGAL

Deal found 2/20

$534

Thu 3/66:00 amLHR - ORD

1 stop12h 55mSWISS

Tue 3/188:05 pmORD - LHR

1 stop11h 55mSWISS

Deal found 2/20

$536

Sat 3/12:10 pmLHR - ORD

Nonstop8h 50mBritish Airways

Tue 3/189:15 pmORD - LHR

Nonstop7h 45mBritish Airways

Deal found 2/20

$537

Wed 4/2311:05 amLHR - ORD

Nonstop8h 45mFinnair

Tue 4/294:55 pmORD - LHR

Nonstop7h 55mFinnair

Deal found 2/20

$542

Thu 2/272:30 pmLHR - ORD

1 stop13h 36mLufthansa

Wed 4/29:20 pmORD - LHR

Nonstop8h 25mLufthansa

Deal found 2/20

$543

Thu 2/273:55 pmLGW - ORD

1 stop29h 35mTAP AIR PORTUGAL

Wed 4/26:00 pmORD - LGW

1 stop14h 00mTAP AIR PORTUGAL

Deal found 2/20

$545

Tue 3/48:05 pmMAN - ORD

2 stops27h 15mMultiple Airlines

Tue 3/117:30 pmORD - MAN

2 stops14h 05mMultiple Airlines

Deal found 2/18

$547

Thu 3/66:40 pmLGW - ORD

1 stop27h 35mSWISS

Mon 3/105:55 pmORD - LGW

2 stops18h 55mSWISS

Deal found 2/20

$549

Best flights from United Kingdom to Illinois
Discover carefully curated flight deals from United Kingdom to Illinois that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated February 20, 2025.

Wed 4/236:00 amLHR - ORD

1 stop12h 10mMultiple Airlines

Tue 4/294:05 pmORD - LHR

Nonstop8h 15mMultiple Airlines

Deal found 2/20

$527

Fri 3/77:40 amLHR - ORD

1 stop12h 30mUnited Airlines

Tue 3/182:16 pmORD - LHR

1 stop10h 39mUnited Airlines

Deal found 2/20

$528

Sat 3/87:40 amLHR - ORD

1 stop12h 30mLufthansa

Wed 3/124:15 pmORD - LHR

1 stop11h 30mLufthansa

Deal found 2/20

$534

Thu 3/66:00 amLHR - ORD

1 stop12h 55mSWISS

Tue 3/188:05 pmORD - LHR

1 stop11h 55mSWISS

Deal found 2/20

$536

Wed 3/1210:25 amLHR - ORD

Nonstop9h 25mAustrian Airlines

Wed 3/266:50 pmORD - LHR

Nonstop8h 05mAustrian Airlines

Deal found 2/20

$537

Tue 4/159:25 pmLHR - ORD

1 stop29h 50mIcelandair

Tue 4/297:30 pmORD - LHR

1 stop10h 25mIcelandair

Deal found 2/20

$539

Thu 3/611:55 amLHR - ORD

Nonstop8h 50mBritish Airways

Mon 3/109:15 pmORD - LHR

Nonstop7h 45mBritish Airways

Deal found 2/20

$540

Wed 3/511:00 amLHR - ORD

Nonstop8h 55mFinnair

Wed 3/124:27 pmORD - LHR

1 stop11h 08mFinnair

Deal found 2/19

$544

Mon 3/241:35 pmLHR - ORD

Nonstop9h 25mBrussels Airlines

Tue 4/19:20 pmORD - LHR

Nonstop8h 25mBrussels Airlines

Deal found 2/20

$547

Tue 3/49:20 pmLGW - ORD

2 stops24h 10mTAP AIR PORTUGAL

Wed 3/268:15 pmORD - LGW

1 stop32h 35mTAP AIR PORTUGAL

Deal found 2/20

$555

Thu 3/209:10 amLHR - MDW

1 stop14h 08mAir France

Thu 3/272:55 pmMDW - LHR

1 stop10h 55mAir France

Deal found 2/20

$558

Thu 4/2411:45 amLHR - MDW

1 stop12h 35mKLM

Mon 4/283:02 pmMDW - LHR

1 stop11h 53mKLM

Deal found 2/20

$560

Last-minute flights from United Kingdom to Illinois
Discover last-minute flight deals from United Kingdom to Illinois. Data last updated February 20, 2025 and is based on user searches.

Fri 2/216:00 amLHR - ORD

1 stop15h 30mTAP AIR PORTUGAL

Fri 2/288:20 pmORD - LHR

1 stop16h 35mTAP AIR PORTUGAL

Deal found 2/20

$534

Tue 2/258:40 pmLHR - ORD

1 stop26h 40mIcelandair

Mon 3/36:30 pmORD - LHR

1 stop19h 00mIcelandair

Deal found 2/20

$531

Wed 2/2611:55 amLHR - ORD

Nonstop8h 50mFinnair

Wed 3/54:16 pmORD - LHR

1 stop10h 19mFinnair

Deal found 2/19

$544

Thu 2/277:55 pmLHR - ORD

1 stop25h 35mTAP AIR PORTUGAL

Wed 4/26:00 pmORD - LHR

1 stop12h 45mTAP AIR PORTUGAL

Deal found 2/20

$528

Thu 2/273:55 pmLGW - ORD

1 stop29h 35mTAP AIR PORTUGAL

Wed 4/26:00 pmORD - LGW

1 stop14h 00mTAP AIR PORTUGAL

Deal found 2/20

$545

Fri 2/286:50 amLHR - ORD

1 stop11h 25mLufthansa

Thu 4/34:05 pmORD - LHR

Nonstop8h 15mLufthansa

Deal found 2/20

$527

Fri 2/282:00 pmLGW - ORD

1 stop26h 37mMultiple Airlines

Wed 3/128:50 amORD - LGW

2 stops18h 15mMultiple Airlines

Deal found 2/20

$556

Fri 2/2812:20 pmLHR - MDW

1 stop11h 51mVirgin Atlantic

Thu 4/32:57 pmMDW - LHR

1 stop11h 58mVirgin Atlantic

Deal found 2/20

$559

Sat 3/17:40 amLHR - ORD

1 stop16h 45mUnited Airlines

Sat 3/158:04 pmORD - LHR

1 stop32h 36mUnited Airlines

Deal found 2/20

$533

Sat 3/12:10 pmLHR - ORD

Nonstop8h 50mBritish Airways

Tue 3/189:15 pmORD - LHR

Nonstop7h 45mBritish Airways

Deal found 2/20

$537

Sat 3/110:25 amLHR - ORD

Nonstop9h 25mAustrian Airlines

Tue 3/181:00 pmORD - LHR

1 stop12h 40mAustrian Airlines

Deal found 2/20

$547

Sat 3/19:10 amLHR - MDW

1 stop14h 33mKLM

Tue 3/182:55 pmMDW - LHR

1 stop10h 55mKLM

Deal found 2/20

$558

One-way flights from United Kingdom to Illinois
Search for one-way flight options from United Kingdom to Illinois. Find affordable one-way fares based on user searches. Data last updated February 20, 2025.

Mon 3/172:00 pmBHX - ORD

3 stops46h 34mMultiple Airlines

Deal found 2/20

$345

Tue 6/312:50 pmMAN - ORD

2 stops36h 27mMultiple Airlines

Deal found 2/19

$350

Wed 3/193:15 pmLHR - ORD

3 stops46h 14mMultiple Airlines

Deal found 2/20

$402

Sat 3/89:15 amLGW - MDW

2 stops34h 58mMultiple Airlines

Deal found 2/20

$403

Tue 3/188:50 pmLHR - MDW

2 stops47h 23mMultiple Airlines

Deal found 2/19

$404

Sat 3/12:00 pmLGW - ORD

2 stops27h 42mMultiple Airlines

Deal found 2/20

$405

Tue 4/155:55 amSTN - ORD

3 stops55h 08mMultiple Airlines

Deal found 2/20

$408

Wed 3/56:40 pmLTN - ORD

2 stops49h 07mMultiple Airlines

Deal found 2/20

$409

Mon 4/77:00 pmLCY - ORD

3 stops40h 46mMultiple Airlines

Deal found 2/19

$448

Wed 3/52:50 pmLHR - ORD

1 stop31h 06mWestJet

Deal found 2/20

$450

Fri 2/282:50 pmLHR - STL

3 stops35h 02mMultiple Airlines

Deal found 2/20

$472

Tue 4/2212:40 pmLGW - MDW

1 stop27h 40mAir Transat

Deal found 2/20

$493

Find flights from United Kingdom to Illinois within your budget

Fly from

Fly to

Route

Depart

Return

Price

LondonChicago

LHR - ORD

LHRORD

London Heathrow

Wed 4/23

6:00 am-12:10 pm

1 stop12h 10m

Chicago O'Hare Intl

Tue 4/29

4:05 pm-6:20 am

Nonstop8h 15m

$527

LondonChicago

LHR - ORD

LHRORD

London Heathrow

Fri 3/7

7:40 am-2:10 pm

1 stop12h 30m

Chicago O'Hare Intl

Wed 3/12

12:48 pm-5:55 am

1 stop12h 07m

$528

LondonChicago

LGW - ORD

LGWORD

London Gatwick

Thu 3/6

2:00 pm-11:28 pm

1 stop15h 28m

Chicago O'Hare Intl

Tue 3/25

9:01 pm-8:05 am

2 stops30h 04m

$532

LondonChicago

LHR - ORD

LHRORD

London Heathrow

Sat 3/8

7:40 am-2:10 pm

1 stop12h 30m

Chicago O'Hare Intl

Wed 3/12

4:15 pm-8:45 am

1 stop11h 30m

$534

LondonChicago

LHR - ORD

LHRORD

London Heathrow

Thu 3/6

6:00 am-12:55 pm

1 stop12h 55m

Chicago O'Hare Intl

Tue 3/18

8:05 pm-1:00 pm

1 stop11h 55m

$536

LondonChicago

LHR - ORD

LHRORD

London Heathrow

Wed 3/12

10:25 am-2:50 pm

Nonstop9h 25m

Chicago O'Hare Intl

Wed 3/26

6:50 pm-7:55 am

Nonstop8h 05m

$537

LondonChicago

LHR - ORD

LHRORD

London Heathrow

Tue 4/15

9:25 pm-9:15 pm

1 stop29h 50m

Chicago O'Hare Intl

Tue 4/29

7:30 pm-11:55 am

1 stop10h 25m

$539

LondonChicago

LHR - ORD

LHRORD

London Heathrow

Thu 3/6

11:55 am-2:45 pm

Nonstop8h 50m

Chicago O'Hare Intl

Mon 3/10

9:15 pm-10:00 am

Nonstop7h 45m

$540

LondonChicago

LHR - ORD

LHRORD

London Heathrow

Wed 4/23

11:05 am-1:50 pm

Nonstop8h 45m

Chicago O'Hare Intl

Tue 4/29

4:55 pm-6:50 am

Nonstop7h 55m

$542

LondonChicago

LGW - ORD

LGWORD

London Gatwick

Thu 3/6

6:40 pm-4:15 pm

1 stop27h 35m

Chicago O'Hare Intl

Mon 3/10

5:55 pm-5:50 pm

2 stops18h 55m

$549

Flights are sorted by cheapest round-trip flights first.

Deals found on 2/20

Showing 1-10 of 60 results

...

Best time to book a flight from United Kingdom to Illinois

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

Estimated round-trip 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.

Travel insights for flights from United Kingdom to Illinois

Get recent, data-driven insights about flights from United Kingdom to Illinois including ideal travel times, pricing trends, and more.

What is the cheapest month to book a flight from United Kingdom to Illinois?

Currently, August is the cheapest month in which you can book a flight from United Kingdom to Illinois (average of $245). Flying from United Kingdom to Illinois in March is currently the most expensive (average of $321). 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 GB to IL?

Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from United Kingdom to Illinois as you normally would.

Weekly flight availability from United Kingdom to Illinois

The most flights from GB0 to USIL are scheduled on a Wednesday (38 on average). You will have fewer flight options on Monday, which is when the least amount of flights are scheduled (33 on average).

Rainfall in Illinois by month

In terms of precipitation, rainfall in Illinois ranges from 1.7 - 4.9 inches per month. August is typically the wettest month, when rainfall can reach 4.9 in. January is typically the driest time to visit Illinois when rainfall is around 1.7 in.

Temperature in Illinois by month

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 73.4 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 23.0 F).

Reviews of airlines servicing Illinois

Read through reviews of airlines operating flights from United Kingdom to Illinois, such as Delta, KLM and Air Transat. Users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.

Delta

8.0

Very good

8,220 reviews

Reviews

1 / 20

10.0

Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception

Delta

8.0

Very good

8,220 reviews

Delta

8.0

Very good

8,220 reviews

Reviews

1 / 20

10.0

Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception

KLM

7.8

Good

1,333 reviews

Delta

8.0

Very good

8,220 reviews

Reviews

1 / 20

10.0

Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception

Air Transat

7.8

Good

380 reviews

Delta

8.0

Very good

8,220 reviews

Reviews

1 / 20

10.0

Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception

LOT

7.6

Good

1,080 reviews

Delta

8.0

Very good

8,220 reviews

Reviews

1 / 20

10.0

Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception

Finnair

7.6

Good

1,273 reviews

Delta

8.0

Very good

8,220 reviews

Reviews

1 / 20

10.0

Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception

Related info for your journey

What are the cheapest airlines to fly from United Kingdom to Illinois one-way?
$450 is the cheapest one-way deal found within the past few days, from WestJet. You may also be able to find cheap deals on Air Transat and Icelandair, with prices starting from $493 and $504, respectively.
Can I find deals for flights from United Kingdom to Illinois that include hotel bookings?
Yes. In addition to deals on United Kingdom to Illinois flights, Cheapflights offers vacation packages that include both flights and hotel.
How can I find direct flights from United Kingdom to Illinois?
After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from United Kingdom to Illinois.
Can I find deals for business class flights from United Kingdom to Illinois?
Yes. Cheapflights offers flight deals from United Kingdom 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 United Kingdom to Illinois?
Currently, August is the cheapest month in which you can book a flight from United Kingdom to Illinois (average of $245). Flying from United Kingdom to Illinois in March is currently the most expensive (average of $321). 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

Top 10 airlines flying from United Kingdom to Illinois

Airline	Cheapest	Average	Flexibility	On-time
Icelandair	Cheapest$390	Average$622	FlexibilityNo cancel fee	On-time76%
Scandinavian Airlines	Cheapest$462	Average$666	FlexibilityNo cancel fee	On-time77%
TAP AIR PORTUGAL	Cheapest$483	Average$729	FlexibilityNo cancel fee	On-timeN/A
Aer Lingus	Cheapest$517	Average$806	FlexibilityNo cancel fee	On-timeN/A
American Airlines	Cheapest$556	Average$782	FlexibilityNo cancel fee	On-time71%
British Airways	Cheapest$559	Average$878	FlexibilityNo cancel fee	On-time70%
United Airlines	Cheapest$579	Average$982	FlexibilityNo cancel fee	On-time69%
Iberia	Cheapest$582	Average$793	FlexibilityNo cancel fee	On-time77%
Finnair	Cheapest$607	Average$866	FlexibilityNo cancel fee	On-time76%
Lufthansa	Cheapest$660	Average$1,067	FlexibilityNo cancel fee	On-time76%

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$345+ Cheap flights from the United Kingdom to Illinois

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 3/17. Fares are subject to change and may not be available on all flights or dates of travel.

Find cheap flights from United Kingdom to Illinois with Cheapflights

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2. Select your favorite providers

3. Compare prices and book

Cheap flight deals from United Kingdom to Illinois

Keep the following information in mind while searching for United Kingdom to Illinois flight deals. Data was last updated February 20, 2025.

Most accurate provider

Most trusted provider

Round-trip from

One-way from

Popular in

Cheapest in

Average price

Good round-trip deal

Good one-way deal

Find flight deals from United Kingdom to Illinois

Cheapest flights from United Kingdom to IllinoisExplore the most affordable flight options available from United Kingdom to Illinois. Find the lowest fares from popular airlines and budget airlines, with prices last updated on February 20, 2025.

Explore the most affordable flight options available from United Kingdom to Illinois. Find the lowest fares from popular airlines and budget airlines, with prices last updated on February 20, 2025.

Find flights from United Kingdom to Illinois within your budget

Best time to book a flight from United Kingdom to Illinois

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

Travel insights for flights from United Kingdom to Illinois

Get recent, data-driven insights about flights from United Kingdom to Illinois including ideal travel times, pricing trends, and more.

What is the cheapest month to book a flight from United Kingdom to Illinois?

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

Find hourly flight availability from United Kingdom 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 February 20, 2025.

Weekly flight availability from United Kingdom to Illinois

Rainfall in Illinois by month

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

Temperature in Illinois by month

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

Reviews of airlines servicing Illinois

Read through reviews of airlines operating flights from United Kingdom to Illinois, such as Delta, KLM and Air Transat. Users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.

Related info for your journey

Find useful and relevant information for your journey from United Kingdom to Illinois. 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 United Kingdom to Illinois one-way?

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

How can I find direct flights from United Kingdom to Illinois?

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

What is the cheapest month to book a flight from United Kingdom to Illinois?

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 United Kingdom to Illinois

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

Top 10 airlines flying from United Kingdom to Illinois

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Travel Smart

Cheapest flights from United Kingdom to Illinois
Explore the most affordable flight options available from United Kingdom to Illinois. Find the lowest fares from popular airlines and budget airlines, with prices last updated on February 20, 2025.