£266 Find Cheap Flights from London to Illinois

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from London to Illinois departing on 27/4. Fares are subject to change and may not be available on all flights or dates of travel. Click the price to replicate the search for this deal.
1 adult
1 adult, Economy, 0 bags

KAYAK searches hundreds of travel sites at once for deals on flights to Illinois

 
These are the airlines KAYAK users have selected most often from within our search results in flight searches from London to Illinois.
These are the airlines KAYAK users have selected most often from within our search results in flight searches from London to Illinois.
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Cheap Flights from London to Illinois

Cheapest return prices found by our users on KAYAK in the last 72 hours
Chicago
Chicagodirect£435
Moline
Moline2 stops£901
Peoria
Peoria2 stops£849
Champaign
Champaign2 stops£872
Chicago
Chicagodirect£435
Moline
Moline2 stops£901
Peoria
Peoria2 stops£849
Champaign
Champaign2 stops£872

Book Cheap London to Illinois Plane Tickets

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for return flights from London to Illinois that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.
Discover the best prices for you by selecting your travel dates on KAYAK.

Recent return flight deals from London to Illinois

Tue, 14 Apr - Tue, 21 Apr
United Airlines Logo
14:10 - 17:20
LHR
-
ORD
9h 10mdirect
United Airlines Logo
15:35 - 08:20
ORD
-
LHR
10h 45m
1 stop
£435United Airlines
Thu, 23 Apr - Thu, 30 Apr
Multiple Airlines Logo
07:00 - 18:15
STN
-
ORD
17h 15m
2 stops
Multiple Airlines Logo
19:25 - 22:55
ORD
-
STN
21h 30m
2 stops
£435Multiple Airlines
Fri, 24 Apr - Fri, 1 May
Icelandair Logo
15:40 - 21:25
LGW
-
ORD
11h 45m
1 stop
Icelandair Logo
22:25 - 14:40
ORD
-
LGW
10h 15m
1 stop
£438Icelandair
Fri, 12 Jun - Mon, 22 Jun
Icelandair Logo
13:05 - 18:15
LHR
-
ORD
11h 10m
1 stop
Icelandair Logo
19:25 - 11:55
ORD
-
LHR
10h 30m
1 stop
£438Icelandair
Thu, 23 Apr - Wed, 29 Apr
TAP AIR PORTUGAL Logo
19:50 - 16:00
LHR
-
ORD
26h 10m
1 stop
TAP AIR PORTUGAL Logo
18:00 - 15:35
ORD
-
LHR
15h 35m
1 stop
£440TAP AIR PORTUGAL
Wed, 13 May - Sat, 23 May
American Airlines Logo
12:00 - 19:30
LHR
-
STL
13h 30m
1 stop
American Airlines Logo
13:45 - 10:30
STL
-
LHR
14h 45m
1 stop
£502American Airlines
Thu, 14 May - Wed, 27 May
American Airlines Logo
09:15 - 19:31
LHR
-
STL
16h 16m
1 stop
American Airlines Logo
14:36 - 10:30
STL
-
LHR
13h 54m
1 stop
£517American Airlines
Fri, 15 May - Wed, 27 May
British Airways Logo
16:25 - 19:30
LHR
-
STL
9h 05mdirect
British Airways Logo
21:35 - 11:35
STL
-
LHR
8h 00mdirect
£521British Airways
Wed, 13 May - Wed, 27 May
British Airways Logo
16:25 - 19:30
LHR
-
STL
9h 05mdirect
British Airways Logo
21:35 - 11:35
STL
-
LHR
8h 00mdirect
£526British Airways
Wed, 22 Apr - Tue, 28 Apr
Finnair Logo
14:30 - 08:30
LGW
-
STL
24h 00m
2 stops
Finnair Logo
10:24 - 10:40
STL
-
LGW
18h 16m
2 stops
£608Finnair
Booking Insights

KAYAK's insights & trends for London to Illinois flights

Get data-powered insights and trends into flights from London to Illinois to help you find the cheapest flights, the best time to fly and much more.

What is the cheapest London to Illinois flight route?

Data is based on round-trip flight searches on KAYAK over the past month.

The cheapest ticket to Illinois from London found in the last 72 hours was to Chicago, at £437 return. The most popular route is from London Heathrow Airport (LHR) to Chicago O'Hare Intl Airport (ORD), and the cheapest round-trip airline ticket found on this route in the last 72 hours was £437.

What is the cheapest time of day to fly to Illinois?

The average price for all round-trip flights from London to Illinois depending on the time of departure, clicked by users on KAYAK in the last 2 weeks.

The cheapest time of day to fly to Illinois is generally in the afternoon, when retur flights cost £646 on average. Morning departures are around 3% cheaper than evening flights, on average. The most expensive time of day to fly to Illinois is generally in the evening, which is peak travel time and where the average cost of a ticket is £667.

Can I save money by flying with a stopover from London to Illinois?

The average return price for all direct flights, flights with one stopover, and flights with two stopovers for the route found by users searching on KAYAK in the last 2 weeks.

No, with an average price for the route of £650, prices are generally cheapest when you fly direct.

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

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for round-trip flights from London to Illinois, removes the top 0.1% to account for outliers, and then takes the median of all values for each month.

The cheapest month for flights from London to Illinois is September, when tickets cost £434 (return) on average. On the other hand, the most expensive months are July and August, when the average cost of return tickets is £654 and £614 respectively.

What’s the cheapest day of the week to fly from London to Illinois?

The average price of all round-trip flights from London to Illinois clicked on KAYAK for each day over the last 12 months.

Your flight ticket price will generally be cheaper if you fly to Illinois on a Wednesday and more expensive on a Sunday. On your return trip to London, you should consider flying back on a Sunday, and avoid Fridays for better deals.

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

To calculate weekly average prices, KAYAK takes all prices for each week before departure over the last year for round-trip flights from London to Illinois, removes the top 0.1% to account for outliers, and then takes the average of all the values for each week.

To get a below-average price on a flight from London to Illinois, you should book around 5 weeks before departure, which saves you about 28% compared to booking last-minute. For the absolute cheapest price, our data suggests you should book 23 weeks before departure.

Good to know - Cheap tickets from London to Illinois

Low seasonJanuary
Cheapest flight£266
Best time to beat the crowds (8% less expensive on average)
Most popular time to fly (24% more expensive on average)
Flight from London Gatwick Airport to St. Louis

Flights from London to Illinois: the best tips from KAYAK users

Insights shared by verified travellers who flew the route from London to Illinois 
Verified travelerFlew with British Airways
LHR
-
ORD
Jun 2025
I wish I'd known that there were food and shopping opportunities at the B gate area. This was a lovely, NOT busy place to spend time. I'd have gone directly there if I'd known. Definitely a nice place to wait.
Verified travelerFlew with British Airways
LHR
-
ORD
Apr 2025
Make sure to allow ample time between connecting flights. I have to hoof it when I realized that TSA required bags to be picked up and rechecked.
MichaelFlew with British Airways
LHR
-
ORD
Apr 2025
Have a light luggage as much as you can. Boarding gate walk is not a joke.
Verified travelerFlew with British Airways
LHR
-
ORD
Jul 2024
Gate 10 is a train wreck because there are multiple gates distinguished by a letter following A10. If possible get there as quickly as possible to find the appropriate gate.
EmilyFlew with British Airways
LHR
-
ORD
Mar 2024
Bring as few liquids as possible or put them in checked bag. They are very strict at Heathrow about all of them fitting into one small ziplock bag

FAQs - booking Illinois flights

  • How does KAYAK find such low prices on flights from London to Illinois?

    KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from London to Illinois.

  • How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from London to Illinois?

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight from London to Illinois is likely to change within 7 days, so travellers know whether to wait or book now.

  • What is the Hacker Fare option on flights from London to Illinois?

    Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional return ticket. You could then fly from London to Illinois with an airline and back with another airline.

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from London to Illinois?

    Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying from London to Illinois up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

Reviews of the top 5 airlines flying from London to Illinois

 
See real verified KAYAK customer reviews for airlines flying from London to Illinois. Airline scores are aggregated from all reviews left by passengers on KAYAK after flying with an airline. KAYAK doesn’t show reviews that are older than 5 years. Learn how KAYAK collects reviews.
Need help choosing which airline to fly with from London to Illinois? KAYAK airline reviews give an overall score for each airline based on loads of factors, including comfort, boarding, in-flight entertainment and more, to make your decision easier. See airline scores according to verified KAYAK customer reviews.
7.6
Austrian AirlinesOverall score based on 901 reviews
7.6Boarding
6.8Entertainment
7.3Comfort
6.8Food
8.1Crew
Airline reviews

We were delayed three hours from Montenegro to Vienna on our outbound flight and then rebooked an extra leg on our trip to the US. Our bags, which Austrian made us check in in Montenegro even though the flight was barely half full, didn't find us for ten days. Then, when we asked for compensation for the delay we were given the runaround that the flight originated outside of the EU. Next time we fly Turkish Air.

8.0 ExcellentNate, Jan 2026
IAD - VIE
Read more Austrian Airlines reviews

We were delayed three hours from Montenegro to Vienna on our outbound flight and then rebooked an extra leg on our trip to the US. Our bags, which Austrian made us check in in Montenegro even though the flight was barely half full, didn't find us for ten days. Then, when we asked for compensation for the delay we were given the runaround that the flight originated outside of the EU. Next time we fly Turkish Air.

My Austrian Air flight from Montenegro to Vienna was delayed by three hours because their plane de-icer was broken and they had to wait for the sun to come up before the ice could melt. This meant we missed our United flight altogether. So I can't speak about United, but I was not impressed by Austrian Air. They made us check in two carry on bags for a 60% full flight, and the bags didn't find us in the US for ten days. The re-routing they arranged included an extra leg, a midnight taxi ride across New Jersey and New York, and a five hour sleep in a hotel. Not impressed.

Excellent flight. The crew was exceptionally attentive and organized. Attention to details is unmatched.

Great! They got my vegetarian meal right, flight was comfortable, they helped store my heavy luggage. Pleasant crew and flight staff.

I did wish they would give us the entire little bottle Bailey's instead of just have 1/2 bottle at a time

My layover in Vienna was supposed to be 35 minutes but because my flight was canceled I had to wait in the airport for an additional 8 hours.

They had me unpack a handbag 2 lbs overweight into another handbag 8 lbs underweight for a Bible.

My flight was canceled and even though I paid אם KAYAK you didn't even answer me and obviously didn't refund my money. I will never buy a ticket through you again.

Accessibility serious problems in Viena airport making it seriousely difficult in in-between gates and boarding travel. Pretens of breakfast and service care in the economy pathetic.

One thing I really liked about Austrian Airlines was that the flight attendants were very kind, and the in-flight entertainment offered many choices. One thing that could be improved is the meal service, since only a vegetarian option was offered — it would be better to have at least two choices

They never clean the toilet, and the food is worse

Wonderful. Quick boarding. Early departure and we arrived 30 minutes early at our destination. Unfortunately, when you arrive early, there is still a departing aircraft at our gate. We had to park for 30 minutes until the gate was clear. So our early arrival was not really early at the gate. Otherwise it was a quick and smooth flight. Appreciated the efficiency.

Chargers didn’t work, no entertainment and we had to wait for taxiing for easily 40 minutes after arriving early. Bags were late too!

No real complaints. The in flight food was much better than I expected. The in flight entertainment was excellent.

Crew was great (professional, attentive, prompt). Snacks for 4 hrs flight is deplorable.

Horrible Flight significantly delayed. Not due to united issue. But trying to rebook connection flight and get information about overnight accommodation was difficult. Agent did not seem to care or have any interest to help.

United Airlines is my preferred airlines and I am thankful for Gary who also help support me on the phone to switch my flight literally last min.

This Japanese airline provides great service and very helpful in assisting their passengers.

Seated dude next to me even though lots of empty rows. But main thing was we sat on the tarmac after landing for 30 minutes because of, in the words of the dude who sat next to me, “operational incompetence”. We got changing directions about where to pick up gate checked bags. Pilot and flight attendant were awesome though.

It was a pretty standard flight... until the almost hour and a half spent on the taxi way. I get that the weather has been poor but the delay had nothing to do with the weather and more to do with a plane with several issues tying up the gate. I get that that happens from time to time but this has been EVERY flight I've been on for the past 5 years and I fly 3 to 5 times a year. This isn't just United... it's American, it's Delta. It's an issue with the entire industry. I work for UPS and packages on a cargo plane get better service than people do these days. Anymore I HATE flying.

The real reason why the flying experience with Icelandair ---was mediocre was because of not being able to enter DC airspace yesterday evening. This obviously was out of your control and do realize this is a safety issue. I did notice---that everything was being done to get us to Washington Dulles and we did arrive at Dulles SAFELY with just a 4 hour delay. Thank you!

The staff was kind and helpful. There was no food, and you needed to bring your own earphones to use the entertainment, which I didn’t know.

They wouldn’t check in my luggage even though I had one checked bag prepaid. So I took my bag to the gate and tried to check it in there and two employees scolded me for bringing a large bag to the gate. I told them I was trying to check it in and that it was prepaid, and they said they couldn’t guarantee that it would arrive at my destination but they finally let me drop it off when boarding the plane and pick it up right after exiting the plane. There was no food, and there was no entertainment.

Overall satisfied and would fly with them again. They could improve the check-in efficiency at BOS, we got backed up because it seemed there were passengers requiring much more time for check in.

The customer service was unbeatable from the wheelchair assist team to the flight attendants. The pilot also did an excellent job managing the turbulence.

Delays at check-in, seemed like they were short ground staff at the time and some passengers needed extra processing.

Problems checking in both on the laptop and on the app. No free seating available at check-in as advertised - must pay for EVERY seat between $23 and $75. No way to cancel seat choice. App menus and site menus are not responsive, and some items are impossible to find. Crew and mobile assistance are friendly and helpful.

Food - Non-Existent. You pay for everything. It is strictly Pay-to-Play!

Again, we paid $ 328.00 for specific seats are were assigned those seats.

Having been prepared for paying for everything on board other than water, coffee and tea the service was OK. Food and drink is expensive but the food was OK if limited in scope. Plane was clean and obviously well serviced. After complaining about having to walk in wind and rain to a get a bus to the airport the same thing happened at Portland. I’m sure you could get a terminal gate flight, complimentary food and drink for not much more money without traipsing through rain and slush in Reykjavik. Not bad but not great.

Everything could have been better. What needed to be wrong with United went wrong

It was good. The seats in economy weren’t bad

Flight map did not work. Crew was great, food was good, plane took off on time and landed early. That's all I can ask.

Very good. Comfortable and I felt well taken care of from start to finish

We were in premium economy seats that appeared to be locked in plae, No reclining. My aching back.

I don’t understand how they charge as much as they do for such a poor experience

I wish the plane had pod seating for business class. I had a window seat (8K) and I had to climb over the person sitting on the aisle when I needed to get up. Also there is no partition between the seats for privacy when sleeping. The Asian airlines have much nicer business class seating. Their seats are wider for better comfort when sleeping.

Paid for exit row at the back of the plane. Window seat with lots of leg space. Food was inedible (as usual). Brought my own.

The seat space seemed small especially when the person ahead reclined but other than that, very good.

Luggage transfer in Chicago was not performed in time. I received my luggage at my destination two days later.

Late takeoff, but on time landing. Lost bags, 3 days to find them, still in transit to my location. Power outlets broken, Wi-Fi not working, so much for working on the long flight.

Good. For a long flight. The comfort of the seat could be better. Also, the food was « normal » plane food. Not indian plane food unfortunately! Everything else was smooth and great.

The seats were comfortable. So many empty seats allowed for stretching out and sleeping. The onboard entertainment was pretty good. The cabin crew were so kind and kept the passengers well- hydrated, and well fed.

We had American Airlines on our return and it was confusing if we were going with Aa or BA I had 2 different flight numbers and didn’t get our gate until it was boarding. So we were a bit nervous as the which it was

My touch screen at my seat wasn't working, the films BA advertised on the website for this flight were not available, and the plane was a little dated, food was good and the staff were good, just let down by the aircraft facilities.

Did not like the seating configuration at all with 2+3+2 in business class. Lacking total privacy and comfort

Check-in experience, for business call please provide a premium experience

Lost my luggage, ran out of food choices in business class, ground crew was completely unapologetic.

Excellent. The crew and flight were great. Checking in was easy and everyone was very helpful.

Entertainment devices on A380 need to be fixed, the seats might do with updates.

Everything you need to know for your flight from London to Illinois

Cabin class types available on flights to Illinois

Cabin classes available on flights to Illinois. Prices are the lowest found on KAYAK over the last 7 days. Price and availability is not guaranteed.