Cheap flights from Illinois to London from £145
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 27/7. 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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Scandinavian Airlines flights from Illinois to London Heathrow Airport
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Icelandair flights from Illinois to London Heathrow Airport
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How to get the cheapest flight ticket from Illinois to London Heathrow Airport
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 Heathrow Airport?
In general, November is the cheapest month to fly from Illinois to London Heathrow Airport. Due to it being the ‘off-season’ during this time, you can expect flight prices to be around £487. The month of January is another great option to travel to London Heathrow Airport, with average flight prices from Illinois averaging around £499.
What is the cheapest day to depart on your flight to London Heathrow Airport?
On average, the least expensive day to fly to London Heathrow Airport from Illinois is on a Wednesday. momondo users have found tickets for Wednesday departures for as low as £526. However, this price may fluctuate depending on the airline, the season, and holidays. Be sure to avoid booking your departure on a Sunday as prices are generally higher than usual. According to our data, the average ticket price to London Heathrow Airport on Sunday is £672.
What is the cheapest time of day to depart on your flight to London Heathrow Airport?
According to our data, the cheapest time of day to fly to London Heathrow Airport is in the morning. momondo users have found flights departing from Illinois to London Heathrow Airport in the morning for as low as £566. Keep in mind that these prices may fluctuate based on what airline you choose and the time of year you plan to travel. If you have a flexible travel schedule, then try to avoid flying in the evening when prices are £618 on average. Flights to London Heathrow Airport from Illinois in the evening are generally more expensive because this time of day is more convenient for travellers’ schedules.
What is the cheapest Illinois to London Heathrow flight route?
Fly from Chicago O'Hare Intl to London Heathrow for the best Illinois - London Heathrow flight prices
How far in advance should I book a flight to London Heathrow Airport?
You are more likely to see cheaper flights to London Heathrow Airport from Illinois when booking 20 weeks ahead of your departure date. In general, you can expect to find flights to London Heathrow Airport for around £584 when searching 20 weeks out.However, flight prices might be lower outside of this timeframe. For example, people recently found flights to London Heathrow Airport from Illinois for as low as £518 on momondo.
What cabin class options are available on Illinois to London Heathrow flights?
There are 4 cabin classes available to choose from on Illinois to London Heathrow 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 Heathrow?
Icelandair, TAP AIR PORTUGAL, and SWISS are the most popular carriers operating from Illinois to London Heathrow
Which airlines fly to London Heathrow Airport?
British Airways, Iberia and United Airlines are the top three most popular airlines that fly to London Heathrow Airport from Illinois according to our data. British Airways is the first choice among our users, with 49% of people opting to fly with this airline when travelling to London Heathrow Airport. Keep in mind that there are 6 different airlines that fly to London Heathrow Airport on a routine basis, so you have a few additional options to choose from.
How many flights depart from Illinois to London Heathrow Airport on average per day?
As of May 2025, 56 flights take off from Illinois and land in London Heathrow Airport 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 Heathrow Airport on average per week?
As of May 2025, 394 flights take off from Illinois and land in London Heathrow Airport each week. The most common flight departure day for this route is Mon, with 14% of weekly flights taking off on this day.
Cheap Illinois to London Heathrow Airport flight deals and tips
Find info about flight duration, direct flights, and airports for your flight from Illinois to London Heathrow Airport
When did momondo last update prices for flights from Illinois to London Heathrow Airport?
Prices for flights from Illinois to London Heathrow Airport refresh daily.
How many operators does momondo search for flights from Illinois to London Heathrow Airport?
As of May 2025, there are 9 operators available to choose from for flights from Illinois to London Heathrow Airport.
How old do you have to be to fly from Illinois to London Heathrow Airport?
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 Heathrow Airport.
What documentation or ID do you need to fly to London Heathrow Airport?
The travel and health documents required for your trip to London Heathrow Airport 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 Heathrow Airport. 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 Heathrow Airport?
momondo data reveals that the most frequently booked plane model on the route from Illinois to London Heathrow Airport is Boeing 787-9 Dreamliner, representing 41.78% of all bookings. The subsequent popular models are Boeing 787-10 Dreamliner at 19.85%, Boeing 777 at 16.78%, and Boeing 767-300 at 10.45%.
Best airlines flying from Illinois to London Heathrow Airport
Compare and see reviews for airlines that fly from Illinois to London Heathrow Airport with momondo
| Airline | Rating | Free Cancellation | Price | ||
|---|---|---|---|---|---|
| PriceFrom £356 | Free Cancellation | Rating 7.6 1,282 reviews | |||
| PriceFrom £382 | Free Cancellation | Rating 7.2 10,000 reviews | |||
| PriceFrom £446 | Free Cancellation | Rating 7.0 2,739 reviews | |||
| PriceFrom £462 | Free Cancellation | Rating 7.4 8,745 reviews | |||
| PriceFrom £475 | Free Cancellation | Rating 6.6 6,918 reviews | |||
| PriceFrom £484 | Free Cancellation | Rating 6.7 7,079 reviews |
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Why should I use momondo to find a flight deal from Illinois to London?
We help find the flight that best suits your needs, momondo compares prices from hundreds of airlines and travel agents and helps you filter them to find the best flight from Illinois to London for 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?
If you are not ready to book a flight from Illinois to London now, use our insights above to find helpful tips or alternatively set up a price alert, where momondo will track prices on flights to London and let you know when they change.