Cheap flights from Illinois to London from £146
This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from Illinois to London departing on 9/8. 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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Icelandair flights from Illinois to London
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TAP AIR PORTUGAL flights from Illinois to London
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How to get the cheapest flight ticket from Illinois to London
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 London?
The cheapest month to fly to London from Illinois is in February. Flight prices, which tend to average around £487, are often lower during this time because this is during the off-season. The month of November is another great option to travel to London, with average flight prices from Illinois averaging around £493.
What is the cheapest day to depart on your flight to London?
Our data shows that Wednesday is the least expensive day to fly to London. Tickets to fly out on this day can be as low as £535. When flying out on a Sunday, the most expensive travel day of the week, you can expect to see flight prices from Illinois to London for around £667.
What is the cheapest time of day to depart on your flight to London?
The cheapest time of day to fly to London is in the afternoon when flights can be purchased for as low as £597. Flights at midday are often more expensive, with an average ticket price of £819.
What is the cheapest Illinois to London flight route?
Fly from Chicago O'Hare Intl to London Heathrow for the best Illinois - London flight prices
How far in advance should I book a flight to London?
You are more likely to see cheaper flights to London from Illinois when booking 3 weeks ahead of your departure date. In general, you can expect to find flights to London for around £588 when searching 3 weeks out.However, flight prices might be lower outside of this timeframe. For example, people recently found flights to London from Illinois for as low as £533 on momondo.
What cabin class options are available on Illinois to London flights?
There are 4 cabin classes available to choose from on Illinois to London 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 Illinois to London?
Icelandair and TAP AIR PORTUGAL are the most popular carriers operating from Illinois to London
Which airlines fly to London?
British Airways, Iberia and United Airlines are the top three most popular airlines that fly to London from Illinois according to our data. British Airways is the first choice among our users, with 45% of people opting to fly with this airline when travelling to London. Keep in mind that there are 6 different airlines that fly to London on a routine basis, so you have a few additional options to choose from.
How many flights depart from Illinois to London on average per day?
As of May 2025, 47 flights take off from Illinois and land in London each day. The most common flight departure time for this route is 21:00, with 65% of daily flights taking off in the evening.
How many flights depart from Illinois to London on average per week?
As of May 2025, 333 flights take off from Illinois and land in London each week. The most common flight departure day for this route is Thu, with 17% of weekly flights taking off on this day.
Cheap Illinois to London flight deals and tips
Find info about flight duration, direct flights, and airports for your flight from Illinois to London
When did momondo last update prices for flights from Illinois to London?
Prices for flights from Illinois to London refresh daily.
How many operators does momondo search for flights from Illinois to London?
As of May 2025, there are 9 operators available to choose from for flights from Illinois to London.
How old do you have to be to fly from Illinois to London?
The minimum age a child must be to fly alone is five but airlines that offer an unaccompanied minor (UNMR) service will have their own age restrictions, including rules around flight length, timings, and stopovers. We always recommend checking with the individual airline you are booking with to travel from Illinois to London.
What documentation or ID do you need to fly to London?
The travel and health documents required for your trip to London can vary based on your itinerary and personal situation. As a rule, consider having multiple documents such as a national ID card or driver’s license, and a passport valid for six-months after you plan to arrive at London. We always recommend checking with your airline or a trusted third party such as IATA to get advice.
What is the most popular plane model from Illinois to London?
Based on momondo bookings for flights between Illinois and London, the leading plane model is Boeing 787-9 Dreamliner, making up 42.24% of the total bookings. Other popular models include Boeing 787-10 Dreamliner with 19.60%, Boeing 777 with 17.55%, and Boeing 767-300 with 8.43%.
Best airlines flying from Illinois to London
Compare and see reviews for airlines that fly from Illinois to London with momondo
| Airline | Rating | Free Cancellation | Price | ||
|---|---|---|---|---|---|
| PriceFrom £357 | Free Cancellation | Rating 7.6 1,275 reviews | |||
| PriceFrom £384 | Free Cancellation | Rating 7.2 10,000 reviews | |||
| PriceFrom £448 | Free Cancellation | Rating 7.0 2,701 reviews | |||
| PriceFrom £477 | Free Cancellation | Rating 6.6 6,846 reviews | |||
| PriceFrom £487 | Free Cancellation | Rating 6.7 7,045 reviews | |||
| PriceFrom £498 | Free Cancellation | Rating 7.4 8,696 reviews |
Travelling to a place near London?
Book flights to London if you plan to visit one of these locationsWhy use momondo?
Why should I use momondo to find a flight deal from Illinois to London?
It is quick and easy to find Illinois to London flights on momondo. We search and return numerous flight options from various airlines and agents. You can then use our filters to narrow your search until you have found the most convenient flight to London that suits you.
Can I find flights from Illinois to London with flexible booking policies on momondo?
All flight searches from Illinois to London on momondo can be filtered to show those which offer flexible booking policies.
How can momondo help me find flights from Illinois to London?
Once you have performed a search for Illinois to London flights, momondo helps you find the right one by offering useful filters to narrow down your flight selection. Flights can be filtered by multiple factors such as airline, airport and price; but also by other criteria like aircraft type and payment method.
I’m not ready to book a flight from Illinois to London right now. Can momondo alert me if prices change?
Yes momondo offers price alerts on flights to London from Illinois. After performing a search on this page you should be able to see the price alert set up feature. Simply provide a valid email address and momondo will instantly alert you when prices change.