Cheap flights from London to Illinois from $266
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 to Illinois departing on 8/27. 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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How to get the cheapest flight ticket from London 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 cheapest month to fly to Illinois from London is in February. Flight prices, which tend to average around $580, are often lower during this time because this is during the off-season. 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 $612.
What is the cheapest day to depart on your flight to Illinois?
The cheapest day to depart from London to Illinois is on a Friday when prices can be found for as low as $805. Flights from London to Illinois on a Sunday will generally be more expensive and average around $940. 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 most recent data shows that the best time of day to fly to Illinois is in the evening. Flights from London to Illinois during this time can be as low as $620. Flights in the afternoon are often more expensive with an average ticket price of $953.
What is the cheapest London to Illinois flight route?
Fly from London Heathrow to Chicago O'Hare Intl for the best London - 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 when booking 13 weeks ahead of your departure date. In general, you can expect to find flights to Illinois for around $742 when searching 13 weeks out.However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Illinois from London for as low as $710 on momondo.
What cabin class options are available on London to Illinois flights?
There are 4 cabin classes available to choose from on London to Illinois flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.
How many flights depart from London to Illinois on average per day?
The number of flights available between London and Illinois is 51 per day as of June 2025. The most frequent departure time is 2:00PM, with 53% of daily flights leaving in the afternoon.
How many flights depart from London to Illinois on average per week?
The number of flights available between London and Illinois is 362 per week as of June 2025. The most frequent departure day is Mon, with 15% of weekly flights leaving on this day.
Cheap London to Illinois flight deals and tips
Find info about flight duration, direct flights, and airports for your flight from London to Illinois
When did momondo last update prices for flights from London to Illinois?
Prices for flights from London to Illinois refresh daily.
How many operators does momondo search for flights from London to Illinois?
The number of operators available for flights from London to Illinois is 11 as of June 2025.
How old do you have to be to fly from London to Illinois?
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 London to Illinois.
What documentation or ID do you need to fly to Illinois?
The required travel and health documents for your Illinois trip may vary depending on your itinerary and personal circumstances. As a general rule, you should carry multiple documents, including a national ID card or driver's license and a passport valid for six months after your intended arrival at Illinois. We recommend that you seek guidance from your airline or a reliable third party such as IATA.
What is the most popular plane model from London to Illinois?
Based on momondo bookings for this flight route, the most popular plane model on flight routes from London to Illinois is Boeing 767-300 (40.03% of total bookings). The next most popular plane models are Boeing 787-10 Dreamliner (20.47%), Boeing 777 (15.62%), and Boeing 777-300ER (7.67%).
Best airlines flying from London to Illinois
Compare and see reviews for airlines that fly from London to Illinois with momondo
| Airline | Rating | Free Cancellation | Price | ||
|---|---|---|---|---|---|
| PriceFrom $390 | Free Cancellation | Rating 7.0 499 reviews | |||
| PriceFrom $462 | Free Cancellation | Rating 7.3 1,387 reviews | |||
| PriceFrom $483 | Free Cancellation | Rating 7.1 1,885 reviews | |||
| PriceFrom $538 | Free Cancellation | Rating 7.4 8,790 reviews | |||
| PriceFrom $551 | Free Cancellation | Rating 6.6 7,008 reviews | |||
| PriceFrom $568 | Free Cancellation | Rating 7.1 1,117 reviews | |||
| PriceFrom $582 | Free Cancellation | Rating 7.0 2,776 reviews | |||
| PriceFrom $583 | Free Cancellation | Rating 7.2 10,000 reviews | |||
| PriceFrom $586 | Free Cancellation | Rating 7.6 802 reviews | |||
| PriceFrom $607 | Free Cancellation | Rating 7.6 1,290 reviews |
Why use momondo?
Why should I use momondo to find a flight deal from London to Illinois?
It is quick and easy to find London to Illinois 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 Illinois that suits you.
Can I find flights from London to Illinois with flexible booking policies on momondo?
Flights from London to Illinois with flexible booking policies can be found by using the search form above and then selecting our dedicated flexible booking filter, which will highlight only the flights where this policy is applied.
How can momondo help me find flights from London to Illinois?
Once you have performed a search in the form on the page, momondo provides useful filters and insights. We can show you the cheapest days and times to fly as well as help filter your options to help you make an informed choice when booking flights to Illinois from London.
I’m not ready to book a flight from London to Illinois right now. Can momondo alert me if prices change?
Of course. momondo tracks the price of London to Illinois flights. All you need is a valid email address and we will do the rest; it is that quick and easy.