£164 Find Cheap Flights from Illinois to the United Kingdom

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1 adult, Economy

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Good to know - Cheap tickets from Illinois to the United Kingdom

Low seasonFebruary
Cheapest flight£164
Best time to beat the crowds (19% less expensive on average)
Most popular time to fly (37% more expensive on average)
Flight from St. Louis to London Gatwick Airport

Flights from Illinois to the United Kingdom: the best tips from KAYAK users

Insights shared by verified travellers who flew the route from Illinois to the United Kingdom 
Learn how KAYAK collects reviews and tips from users.
Verified travelerFlew with British AirwaysORD-LHRJun 2025
Get a wheel chair if you have difficulty walking
JoeFlew with IberiaORD-LHRApr 2025
Get there early. Nice airport options while you wait.
Verified travelerFlew with IberiaORD-LHRMay 2025
Get to the airport early so you’re relaxed. Con yourself into believing it’s bedtime and try to sleep so that you can keep going all day when you get there. If you can afford more comfy seats it might be worth it - though I always have the cheap ones so I can’t say for sure. Try very hard not to. sit in the middle. I’m small and the guy next to me played games all night and didn’t care that he continually ( with every move) jabbed me with his arm. This was my first flight with Cheap Flights and it was far less convenient than other times I’ve flown overseas.
DinaFlew with United AirlinesORD-LHRJan 2025
Anticipate delays, prepare for long walks through Heathrow to baggage claim or for connections.
KariFlew with British AirwaysORD-LHRMay 2024
Always check to confirm your assistance is in system. No wheelchair waiting for me in London. Had no clue about airport or how to get around. Got lost easy
AaronFlew with American AirlinesORD-LHRDec 2023
Find a flight where you are allowed to choose your seats before the day of boarding for anything international.

FAQs for booking flights from Illinois to the United Kingdom

  • How does KAYAK find such low prices on flights from Illinois to the United Kingdom?

    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 Illinois to the United Kingdom.

  • How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Illinois to the United Kingdom?

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight from Illinois to the United Kingdom 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 Illinois to the United Kingdom?

    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 Illinois to the United Kingdom 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 Illinois to the United Kingdom?

    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 Illinois to the United Kingdom up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

  • Which airlines fly most frequently to the United Kingdom?

    American Airlines connects Illinois to the United Kingdom with 49 flights per week. Alaska Airlines also offers 49 flights per week, while British Airways follows with 49 flights per week.

  • How many airports are there in the United Kingdom?

    There are 39 airports in the United Kingdom. The busiest airport is London Heathrow Airport (LHR), with 45% of all flights arriving there.

  • Which is the cheapest airport to fly into in the United Kingdom?

    Prices will differ depending on the departure airport, but generally, the cheapest airport to fly to in the United Kingdom is London Heathrow Airport (LHR), with an average flight price of £398.

  • What is the cheapest day to fly to the United Kingdom?

    Based on KAYAK data, the cheapest day to fly to the United Kingdom is Thursday when return tickets can be as cheap as £515. On the other hand, the most expensive day to fly is Saturday, when return prices are £656 on average.

  • What is the cheapest time of day to fly to the United Kingdom?

    The cheapest time of day to fly to the United Kingdom is generally in the morning, when retur flights cost £714 on average. Morning departures are around 7% cheaper than evening flights, on average. The most expensive time of day to fly to the United Kingdom is generally in the afternoon, which is peak travel time and where the average cost of a ticket is £933.

  • What is the cheapest flight to the United Kingdom?

    The cheapest ticket to the United Kingdom from Illinois found in the last 72 hours was to London Heathrow Airport, at £435 return. The most popular route is Chicago O'Hare Intl Airport (ORD) to London Heathrow Airport (LHR) and the cheapest return airline ticket found on this route in the last 72 hours was £435.

  • What is the cheapest month to fly from Illinois to the United Kingdom?

    The cheapest month for flights from Illinois to the United Kingdom is January, when tickets cost £414 (return) on average. On the other hand, the most expensive months are May and June, when the average cost of round-trip tickets is £901 and £748 respectively.

  • How far in advance should I book a flight from Illinois to the United Kingdom?

    To get a below-average price on the flight from Illinois to the United Kingdom, you should book around 1 week before departure. For the absolute cheapest price, our data suggests you should book 3 weeks before departure.

  • How many cities have direct flights to the United Kingdom?

    From Illinois, there are direct flights to the United Kingdom from one city. This city is Chicago and there are 486 direct flights each week.

  • How many direct flights to the United Kingdom are there each day?

    There are around 63 direct flights from within Illinois to the United Kingdom every day. Most flights (54%) depart in the evening.

  • How many direct flights to the United Kingdom are there each week?

    Each week there are around 437 direct flights from within Illinois to the United Kingdom. The most common day for departures is Monday, with 14% of flights taking off on this day.

  • How long is the flight to the United Kingdom?

    An average direct flight from Illinois to the United Kingdom takes 13h 29m, covering a distance of 3895 miles. The shortest route is Chicago O'Hare Intl Airport (ORD) to London Heathrow Airport (LHR) with an average flight time of 7h 40m.

  • How many long-haul flights are there to the United Kingdom each week?

    There aren’t any medium-haul (3-6 hour flight duration) or short-haul (up to 3 hour flight duration) flights to the United Kingdom. Instead, there are 486 long-haul flights (6-12 hour flight duration), with the most arriving from Chicago.

  • What are the most popular destinations in the United Kingdom?

    Based on KAYAK flight searches, the most popular destination is London (87% of total searches to the United Kingdom). The next most popular destinations are Edinburgh (6%) and Manchester (2%). Searches for flights to Southampton (1%), to Birmingham (1%), and to Belfast (1%) are also popular.

Everything you need to know for your flight to the United Kingdom

Cabin class types available on flights to Illinois

Cabin classes available on flights to Illinois. Prices are the lowest found on KAYAK over the last 7 days. Price and availability is not guaranteed.
First Class flights to the United Kingdomfrom £3,946
Business Class flights to the United Kingdomfrom £2,725
Prem Econ Class flights to the United Kingdomfrom £3,988
Economy class flights to the United Kingdomfrom £321

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