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Cheap Flights from Heathrow to Illinois

Cheapest return flight prices found by our users on KAYAK in the last 5 days
Chicago
Chicago1 stop£512
Moline
Moline2 stops£770
Springfield
Springfield2 stops£844
Champaign
Champaign1 stop£865
Peoria
Peoria2 stops£754
Bloomington
Bloomington2 stops£4,624
Chicago
Chicago1 stop£512
Moline
Moline2 stops£770
Springfield
Springfield2 stops£844
Champaign
Champaign1 stop£865
Peoria
Peoria2 stops£754
Bloomington
Bloomington2 stops£4,624
Booking Insights

KAYAK's insights & trends for Heathrow to Illinois flights

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

How much is a return flight from London Heathrow Airport to Illinois?

Flight prices are below average for this route right now.

Flights to Illinois from London Heathrow Airport usually cost between £579 and £751 in November.
The lowest price found in the past 5 days was £512 on Scandinavian Airlines (23 Nov–7 Dec).

What is the cheapest London Heathrow Airport to Illinois flight route?

The cheapest ticket to Illinois from London Heathrow Airport found in the last 5 days was to Chicago, at £474 return. The most popular route is from London Heathrow Airport (LHR) to Chicago O'Hare Intl Airport (ORD), and the cheapest return airline ticket found on this route in the last 5 days was £474.

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

The cheapest time of day to fly to Illinois is generally in the afternoon, when retur flights cost £674 on average. On average, there is no price difference when choosing to fly in the morning or the evening on this flight route. 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 £722.

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

No, with an average price for the route of £672, prices are generally cheapest when you fly direct.

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

The cheapest month for flights from London Heathrow Airport to Illinois is February, when tickets cost £503 (return) on average. On the other hand, the most expensive months are August and July, when the average cost of return tickets is £826 and £799 respectively.

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

If you are looking for a flight deal from London Heathrow Airport to Illinois, look for departures on Wednesdays and avoid leaving on a Sunday, as it's usually the priciest day. When flying back from Illinois, Monday is the cheapest day to fly and Saturday is the most expensive.

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

To get a below-average price on a flight from London Heathrow Airport to Illinois, you should book around 5 weeks before departure, which saves you about 24% compared to booking last-minute. For the absolute cheapest price, our data suggests you should book 17 weeks before departure.

Good to know - Cheap tickets from London Heathrow Airport to Illinois

Low season

January

Cheapest flight

£392
Best time to beat the crowds (8% less expensive on average)
Most popular time to fly (26% more expensive on average)
Flight from London Heathrow Airport to Chicago O'Hare Airport

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

Insights shared by verified travellers who flew the route from Heathrow to Illinois 
Verified travelerFlew with Austrian Airlines-Sept 2026
Never plan any close connections in O'Hare. I give myself at least 3 hours if I have a connection. Nothing is convenient and if you need to change terminals, and you usually do, it takes forever. In addition, customs takes a long time. I entered the UK more easily than I got back into the country of my birth. Heathrow is not bad unless you need to go from any other terminal to Terminals 4 & 5. That is difficult bc there is no clear signage. Don't be afraid to ask for help. I have found people ready to help, especially if you are a senior.
Verified travelerFlew with British Airways-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-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-Apr 2025
Have a light luggage as much as you can. Boarding gate walk is not a joke.
Verified travelerFlew with British Airways-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-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 Heathrow Airport 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 Heathrow Airport to Illinois.

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

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight from London Heathrow Airport 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 Heathrow Airport 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 Heathrow Airport 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 Heathrow Airport 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 Heathrow Airport 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 Heathrow to Illinois

 
Need help choosing which airline to fly with from Heathrow 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.
7.4
Scandinavian AirlinesOverall score based on 2025 reviews
6.8Entertainment
7.4Comfort
6.8Food
8.1Crew
7.7Boarding
Airline reviews

Didn't care much for the food but maybe that's just because I'm American and the food was very European. Would have liked a second alcoholic beverage service in a 7-8 hour flight. I was offered two wines to have with dinner though and should have accepted both. I didn't realize they would only offer alcohol once. Lights were never turned off in the cabin for sleeping. Flight was delayed several hours with zero explanation from SAS. However, the flight attendants were fantastic. We were traveling with a friend who needed oxygen and they were very attentive and helped him throughout the flight. That was greatly appreciated. The pillows and blankets are great. Gift bags with toothbrush etc so nice! This was our first time traveling Premium so alot of perks we were used to getting! The flight was smooth and I loved watching the planes location on the seat screen and being able to watch movies etc. overall it was great I would definitely recommend SAS to anyone and hope to fly with you again sometime.

10.0 ExcellentKay, Sept 2026
Read more Scandinavian Airlines reviews

Didn't care much for the food but maybe that's just because I'm American and the food was very European. Would have liked a second alcoholic beverage service in a 7-8 hour flight. I was offered two wines to have with dinner though and should have accepted both. I didn't realize they would only offer alcohol once. Lights were never turned off in the cabin for sleeping. Flight was delayed several hours with zero explanation from SAS. However, the flight attendants were fantastic. We were traveling with a friend who needed oxygen and they were very attentive and helped him throughout the flight. That was greatly appreciated. The pillows and blankets are great. Gift bags with toothbrush etc so nice! This was our first time traveling Premium so alot of perks we were used to getting! The flight was smooth and I loved watching the planes location on the seat screen and being able to watch movies etc. overall it was great I would definitely recommend SAS to anyone and hope to fly with you again sometime.

My daughter always gets sick when we order the gluten free meal option. Internet didn’t work as advertised.

The flight was very cold, and the seats were rather uncomfortable. The food has been better on our other SAS experiences. Most significantly, the luggage with most of my wife's personal items and clothes didn't make the flight. Hoping for a quick resolution, but no real opportunity to speak with a Human has us concerned.

It was so hot on the plane. No air jets above the seats

Online check in of SAS is very poor. Even the kiosks at London had system problems. Either it would print boarding tickets or luggage tags. Many other customers had problems . SAS staff was good and helped.

Please see my comments for the flight from Chicago to Copenhagen

We were sitting in SAS plus. Super friendly, service that went above and beyond on a Full Flight too! Meals were deliscious and trays were cleared promptly. Generous drinks offered throughout the flight. Would like to suggest better movies on offer to watch.... In all genres and maybe more cooking shows? There was only 1, Nadia's Everyday Baking... Thank you

When we arrived in Bergen and opened our suitcases, we were shocked! We checked 2 of 3 suitcases and the contents of these 2 suitcases was completely wet!!! It was raining in Oslo and Bergen, but not a hard rain. It seems that someone had gone through our suitcases. There was even sand in the suitcase such that everything had to be laundered when we got to Bergen! We had plastic bags in our suitcases and they had been opened and the interiors of the bags were wet!!! Our valuables were all in our carry-on so nothing was actually stolen. What happened here was unacceptable! There is someone working for Scandinavian Airlines who is not honest and really messed things up for us. Not so sure I would fly SAS again… Marna Skaar

This was my first time flying SAS and used them for 4 flights. The crews, flight and communication was outstanding. I flew premium economy and was extremely impressed by their SAS lounges. I will 100% ise SAS again. Everyone was so pleasant!

Little space and no pad provide for lie flat seats in business, Movies were limited and grouping very strange.

Overall good. however, we were rerouted and my luggage was lost.

Like getting a bus. No great luxury but will get you there

Got us to destination alive, albeit a bit late. Luggage was left behind. No live tracking app available (available on some other airlines). Supposedly going to be delivered in next couple of days.

I had zero issues with the flight. I did have issues with the staff at the airport. We missed out flight due to a delay with another airline. Talking to the staff and trying to get a new flight arranged was challenging. One guy was able to try to help us and got us on a new flight, but other staff was dismissive and clearly let us know it wasn’t their problem. All I kept thinking was… this is why air lingus has such a poor customer service reputation. I will be avoiding this airline in the future.

I liked that I went thru customs in Dublin instead of having to do that in LA.

Baggage fees are deceptive! When I booked this flight, I purchased two tickets and had indicated that I wanted one checked bag. That increased the ticket price by about $100 PER TICKET!. When we went to check in, I was told that I could only check ONE bag, even though I had purchased TWO tickets. I had to pay an additional $50 each way for my wife’s bag. In my opinion, I paid twice for her bag.

Delays resulting in missed connecting flight. Attendant failed to arrange special assistance as promised to get us on connecting flight. Robyn was the particular attendant.

Very good except for the boarding process which was more hectic than it should have been

This was the most expensive economy flight per minute of flight time ever. But the quality was lacking. Extremely Aer Lingus rude staff at LHR said that the flight from London to Dublin (Ireland) was “NOT international.” Horrified at the colonial and imperial perspective. Seats were dirty with trash in seat pockets. Airline doesn’t clean or care about hygiene and safety.

The ease of boarding was good. I wish they had something to eat on the plane.

Let's just say I won't do it again.

1. No food on a 8 hr flight is a travesty! The fare was not that low. 2. The entertainment was pretty bad and you had to buy headphones!!! 3. Only 2 toilets for the whole Economy section!!

At least one soda free, felt like I was nickeled to death.

If there was a disclaimer regarding food service or lack thereof, l missed it. If l had known l would have prepared better. Same with transferring at Reykjavik. No information about disembarking via stairs into rain, slush and puddles deep enough to swallow a foot. After being treated to haute cuisine restaurants and warm inviting environment during the flight, the airport is, let’s be kind, disappointing. Plane was comfortable, Airbus, staff were welcoming enough. I would likely try the route again. Maybe have a night and day in Iceland. Maybe not.

Comfort of seats is not good. Like sitting on a rock for 6 hours. Also no in flight food and limited beverages unless you pay is not nice. Need flight to be dark during the “night” but attendants don’t ask for shades to be lowered..

For an economy lite experience, it's by far the best I've had. New planes, clean, great destinations. Very happy to have discovered Iceland Air.

Good. Lacking overhead bin space. No food offered but you can order online or in flight and pay for snacks.

did internet check in but still had to get checked in at the counter and this was not the first time. Bummer!

We had to be bussed to the plane. And it was raining. Not a pleasant experience.

Paying $75 for my bag is disgusting. Got off ground late so I missed my connections. Kept us waiting for passengers in the cold. Will not use them again.

As always, Lufthansa checked my carry-on luggage, even though I was in front of the line. No other airline in the world does this. It's so annoying and unnecessary. There was enough space for it in the overhead bin. It's a TUMI Continental Carry-On. If you have the chance, rather fly easyJet or Condor on this route.

Someone sat in my seat and this made boarding protracted and unpleasant. The stewardesses kept saying, “it is important that everyone be seated — or we will be further delayed,” but for a long time they did not tell me where to sit. At the end of the flight a baby screamed loudly for several minutes and it took ninety minutes (!) to get through EU passport and customs. We had to stand the whole time in a an overheated room. The seat on the plane was narrow. These things are not all Lufthansa’s fault but they made for a somewhat unpleasant trip.

Everything about the flight was excellent except for the fact that we had to wait one hour on the tar app and then I had to race to catch my connecting flight with the next stop

The flight on time, flawless check in and boarding process, the crew was very friendly.

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.

Other than problems with checking in and uploading passport info everything was great. It would be nice to be able to manually input passport info. Often while traveling the bandwidth has problems uploading pictures

Boarding was a zoo. London ground crew was useless. Poor communication regarding where to line up. We were group 2, and everyone was jammed in together. Ground crew didn’t seem to care.

Horrible flight attendant in back of economy that screamed at me, have already reported to United. Horrible food - for Gluten free, why would you assume the person is vegetarian? I was served some kind of horrible curry bean paste and multiple cold rolls and soggy vegetables with no seasoning... um no!

Knowing that there was weather in other areas of the world, united airlines should have planned better than it did. The flight was 5 hours late. United has no regard for its customers

Flight itself fine, big problem with KAYAK. Revised e-ticket sent in July stated departure LHR 10:55, arrival SFO 13:45. (a believable local arrival time given flight length and time difference). When we got to LHR there was no 10:55 flight to SFO and were advised that in fact flight LH2473 was arriving in MUNICH at 13:45pm, and that we would need to get a connecting flight arriving in SFO at 18:55 local time - over 5 hours later than expected. 1) you the booking agent made an error on the revised e-ticket you sent, omitting the Munich stopover and incorrect SFO arrival time. 2) I booked a DIRECT flight and 3) we had to cancel plans this end as a result, even though the team at LHR did a great job moving us to a later direct flight getting us in 2 hours earlier than the flight from munich would have.

need more US friendly food options. Directions on getting to the next gate were terrible - resulted in long walks to the terminal and then finding I couldn;t enter there and had long walk back, then train to security then train back to where I started in the first place

I will never want to book with these people. They are arrogant and rude. Food was really really bad, crew was even worst

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

Everything. Employees offered to help me because I had to use a cane.

Unfortunately, my flight was cancelled because of some sort of emergency over the Atlantic and had to return to London. While I think British Airways made every effort to mitigate the situation, I must say it was still pretty unpleasant. I do appreciate the fact, however, that British Airways put my safety first…and I think the effort to correct a bad situation was very sincere. But I think the process might be handled better in future.

The seat pads are past there sell by date now and are uncomfotable. Also, with screens in the back of the seat, the seats shouldnt be able to recline as this puts rhe screen in your face.

As I have said it sucked, the ticket counter to have to find and pay for another airline to get home. Now I understand this happened over the weekend but they should have someone there to talk to us instead of throwing the regular crew under the bus.

Not so good with their baggage handling as they damaged one of my check in luggage

This flight from London to Chicago was actually on an AA airline. I did book through BA but the flight was AA. Great flight, hectic in Chicago, I wouldn't choose to fly through Chicago again, but that's not the airlines fault. The flight itself was great.

Seats were way too small. I got claustrophobic waiting for trash from meal to be taken away. I couldn't move to even close my tray until trash was taken.

More options for your flight from Heathrow to Illinois

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