£358 Find Cheap Flights from London Heathrow Airport 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 Heathrow to Illinois departing on 10/5. 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.
Travellers love KAYAK
41,299,237 searches in the past 7 days on KAYAK

Save 27% or moreCompare multiple travel sites with one search.

Track pricesNot ready to book? Create a price alert for when prices drop.

Bundle and saveSave money when you bundle your flight + hotel.

Filter your dealsChoose cabin class, free Wi-Fi and more.

Flight Deals
Booking Insights
Flight Deals

Cheap Flights from Heathrow to Illinois

Cheapest return prices found by our users on KAYAK in the last 72 hours
Chicago
Chicagodirect£437
Moline
Moline2 stops£861
Peoria
Peoria2 stops£853
Bloomington
Bloomington3 stops£841
Champaign
Champaign1 stop£874
Chicago
Chicagodirect£437
Moline
Moline2 stops£861
Peoria
Peoria2 stops£853
Bloomington
Bloomington3 stops£841
Champaign
Champaign1 stop£874

Book Cheap Heathrow to Illinois Plane Tickets

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for return flights from Heathrow 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 Heathrow 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
£437United Airlines
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
£441TAP AIR PORTUGAL
Tue, 23 Jun - Tue, 7 Jul
Icelandair Logo
13:05 - 21:25
LHR
-
ORD
14h 20m
1 stop
Icelandair Logo
19:25 - 11:55
ORD
-
LHR
10h 30m
1 stop
£444Icelandair
Wed, 24 Jun - Tue, 7 Jul
Icelandair Logo
13:05 - 18:15
LHR
-
ORD
11h 10m
1 stop
Icelandair Logo
19:25 - 11:55
ORD
-
LHR
10h 30m
1 stop
£445Icelandair
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
£503American Airlines
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
£516British Airways
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
£523British Airways
Thu, 14 May - Sat, 23 May
American Airlines Logo
09:45 - 19:33
LHR
-
STL
15h 48m
1 stop
American Airlines Logo
13:45 - 10:30
STL
-
LHR
14h 45m
1 stop
£526American Airlines
Mon, 27 Apr - Mon, 4 May
Lufthansa Logo
13:30 - 22:57
LHR
-
PIA
15h 27m
2 stops
Lufthansa Logo
13:35 - 06:45
PIA
-
LHR
11h 10m
1 stop
£853Lufthansa
Sat, 25 Apr - Sat, 2 May
Lufthansa Logo
13:30 - 22:57
LHR
-
PIA
15h 27m
2 stops
Lufthansa Logo
13:35 - 08:30
PIA
-
LHR
12h 55m
1 stop
£886Lufthansa
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?

This analysis is based on the cheapest return trip price found on KAYAK in the last 12 months by searching for a flight from London Heathrow Airport to Illinois departing in April.

What is the cheapest London Heathrow Airport 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 Heathrow Airport found in the last 72 hours was to Chicago, at £440 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 £440.

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

The average price for all round-trip flights from London Heathrow Airport 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 £649 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 £670.

Can I save money by flying with a stopover from London Heathrow Airport 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 £664, prices are generally cheapest when you fly direct.

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

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for round-trip flights from London Heathrow Airport 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 Heathrow Airport to Illinois is September, when tickets cost £447 (return) on average. On the other hand, the most expensive months are July and August, when the average cost of return tickets is £647 and £616 respectively.

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

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

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, Sunday is the cheapest day to fly and Friday is the most expensive.

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

Low seasonJanuary
Cheapest flight£358
Most popular time to fly (17% 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 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 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

 
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 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
United AirlinesOverall score based on 9428 reviews
7.7Boarding
8.1Crew
6.6Food
7.3Comfort
7.1Entertainment
Airline reviews

Would've been great if Lufthansa union cockpit pilots didn't strike for 2 days and caused a chaos to my returning plans to USA, and then after rebooking a flight 2 days later tge plane departed 35 min later. So I did not have a good experience.

6.0 GoodAnonymous, Mar 2026
FRA - ORD
Read more United Airlines reviews

Would've been great if Lufthansa union cockpit pilots didn't strike for 2 days and caused a chaos to my returning plans to USA, and then after rebooking a flight 2 days later tge plane departed 35 min later. So I did not have a good experience.

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.

All aspects were excellent - it helped that the flight was only 2/3 full and I had no one sitting in my row. The Pre-check (US Passport Control and Customs) in Dublin made everything so easy when we arrived in Chicago.

I love the direct flights. It saves a lot of hassle and allows immigration and customs in Ireland, making arrival much easier.

One of the best flight experiences I've have had in along time. Would fly with them again.

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.

So, the trip from Dublin to LA did not really happen because the flight took off before we could finish the transfer.

Very nice experience. Flight had good entertainment system and good food options. Customer service was very friendly and nice as well.

The connection time between the regional flight (from Newcastle) to an international flight (to The States) was too short. To require as second security scan and customs clearance within an hour and 20 mins is not enough time to make the actual connection. We had a final boarding call the minute we walked out of US customs and had to sprint (with two small children) through 20 gates to make it in time before the door closed. The concept is great in theory to clear customs before leaving Europe, but the timing needs to be adjusted. We travel abroad frequently and won’t be using this route again. Thanks.

Like - the crew were nice Dislike - sitting on the tarmac for long periods after boarding and landing.

I was not admitted to the flight!!! i need a refund for this.

Waiting area on top of stairs before Boarding the bus wasn’t great. Took a long time to load the bus to gate.

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!

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.

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

Never again. Terrible hospitality and human decency for an international flight. No food, no snacks, no beverages, blankets, pillows, limited entertainment. Tiny seats without any cushion and some do not even recline. I was shocked that they did not charge for seat belts. Never in my life have I witness asking for "spare change" for charity before landing on both legs of the flight. Icelandair can contribute on their own to said, so called, children's charity with the money saved from providing 3 centimeters of tea and water to hungry and dehydrated passengers.

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.

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.

Iceland air transfer was bad. They lost my luggage and I just received it 11/1

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.

the service on Business class should be improved to be at par with industry leaders like Cathay Pacific and Singapore AIrlines. A lot of room for improvement.

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.

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

Information on your arrival and departure airports