Cheap flights from London Heathrow Airport to Illinois from £213
This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from London Heathrow Airport to Illinois departing on 17/9. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.
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TAP AIR PORTUGAL flights from London Heathrow Airport to Illinois
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Icelandair flights from London Heathrow Airport to Illinois
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How to get the cheapest flight ticket from London Heathrow Airport to Illinois
Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip
What is the cheapest month to fly to Illinois?
The month of February is, on average, the cheapest month to fly to Illinois from London Heathrow Airport, with most prices found around £436. If you aren’t able to travel to Illinois during the month of February, then flying in March is also cheap. Prices for this month can be found on momondo for an average of £441.
What is the cheapest day to depart on your flight to Illinois?
The cheapest day to depart on your flight to Illinois is on a Wednesday when prices can be found for as low as £597. This is often the case because there is less demand to fly during this day of the week. Flights from London Heathrow Airport to Illinois on a Sunday will generally be more expensive and average around £654. Keep in mind that these prices on both days could fluctuate depending on the season and the demand.
What is the cheapest time of day to depart on your flight to Illinois?
Our data shows that the cheapest London Heathrow Airport to Illinois flights are usually those with departure times in the evening. Our users have found flights to Illinois in the evening for as low as £544. In the afternoon is when there is more demand to fly to Illinois, so prices are often more expensive at around £656 per ticket.
What is the cheapest London Heathrow to Illinois flight route?
Fly from London Heathrow to Chicago O'Hare Intl for the best London Heathrow - Illinois flight prices
How far in advance should I book a flight to Illinois?
You are more likely to see cheaper flights to Illinois from London Heathrow Airport when booking weeks ahead of your departure date. In general, you can expect to find flights to Illinois for around £540 when searching weeks before you fly. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Illinois from London Heathrow Airport for as low as £518 on momondo.
What cabin class options are available on London Heathrow to Illinois flights?
There are 4 cabin classes available to choose from on London Heathrow to Illinois flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.
What is the cheapest airline that flies from London Heathrow to Illinois?
TAP AIR PORTUGAL, Aer Lingus, and Lufthansa are the most popular carriers operating from London Heathrow to Illinois
Which airlines fly to Illinois?
British Airways, Finnair and Lufthansa are the top three most popular airlines that fly to Illinois from London Heathrow Airport according to our data. British Airways is the first choice among our users, with 63% of people opting to fly with this airline when travelling to Illinois. Keep in mind that there are 15 different airlines that fly to Illinois on a routine basis, so you have a few additional options to choose from.
How many flights depart from London Heathrow Airport to Illinois on average per day?
As of June 2025, there are 46 flights per day flying from London Heathrow Airport to Illinois. The most common time of day flights depart is 14:00, with 50% of flights taking off in the afternoon.
How many flights depart from London Heathrow Airport to Illinois on average per week?
As of June 2025, 324 flights take off from London Heathrow Airport and land in Illinois each week. The most common flight departure day for this route is Mon, with 15% of weekly flights taking off on this day.
Cheap London Heathrow Airport to Illinois flight deals and tips
Find info about flight duration, direct flights, and airports for your flight from London Heathrow Airport to Illinois
When did momondo last update prices for flights from London Heathrow Airport to Illinois?
Prices for flights from London Heathrow Airport to Illinois refresh daily.
How many operators does momondo search for flights from London Heathrow Airport to Illinois?
There are 16 operators available for flights from London Heathrow Airport to Illinois as of June 2025.
How old do you have to be to fly from London Heathrow Airport to Illinois?
The minimum age for a child to fly alone is five, but airlines offering an unaccompanied minor (UNMR) service may have their age restrictions, such as regulations concerning flight duration, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from London Heathrow Airport to Illinois.
What documentation or ID do you need to fly to Illinois?
The travel and health documents you'll need for your trip to Illinois may differ based on your itinerary and personal situation. Typically, you should have several documents on hand, such as a national ID card or driver's license and a passport that is valid for six months after your intended arrival at Illinois. It is always advisable to seek advice from your airline or a trusted third party, such as IATA.
What is the most popular plane model from London Heathrow Airport to Illinois?
Based on momondo bookings for this flight route, the most popular plane model on flight routes from London Heathrow Airport to Illinois is Boeing 767-300 (41.88% of total bookings). The next most popular plane models are Boeing 787-10 Dreamliner (19.35%), Boeing 777 (15.69%), and Boeing 777-300ER (6.89%).
Best airlines flying from London Heathrow Airport to Illinois
Compare and see reviews for airlines that fly from London Heathrow Airport to Illinois with momondo
| Airline | Rating | Free Cancellation | Price | ||
|---|---|---|---|---|---|
| PriceFrom £337 | Free Cancellation | Rating 7.0 506 reviews | |||
| PriceFrom £346 | Free Cancellation | Rating 7.3 1,412 reviews | |||
| PriceFrom £360 | Free Cancellation | Rating 7.1 1,903 reviews | |||
| PriceFrom £377 | Free Cancellation | Rating 7.4 654 reviews | |||
| PriceFrom £386 | Free Cancellation | Rating 7.3 358 reviews | |||
| PriceFrom £390 | Free Cancellation | Rating 6.8 7,191 reviews | |||
| PriceFrom £393 | Free Cancellation | Rating 7.6 805 reviews | |||
| PriceFrom £394 | Free Cancellation | Rating 7.4 8,838 reviews | |||
| PriceFrom £396 | Free Cancellation | Rating 7.2 10,000 reviews | |||
| PriceFrom £399 | Free Cancellation | Rating 6.6 7,067 reviews |
Why use momondo?
Why should I use momondo to find a flight deal from London to Illinois?
To find the flight that best suits your needs, momondo gathers a range of flights from a large pool of different airlines and agents; you can then use our insights and filters to find and book the right flight to Illinois from London.
Can I find flights from London to Illinois with flexible booking policies on momondo?
Yes. momondo allows you to filter the results for London to Illinois flights to just show those with flexible booking policies.
How can momondo help me find flights from London to Illinois?
Once all potential London to Illinois flight options are in front of you, momondo lets you sort and filter flights based on preferences such as airline, price and flight times amongst many other options.
I’m not ready to book a flight from London to Illinois right now. Can momondo alert me if prices change?
If you are simply researching potential flights to Illinois, momondo offers a useful price alert feature which will track prices for flights to Illinois from London and alert you when they change.