Cheap flights from the United Kingdom to Illinois from £280

The month of February is, on average, the cheapest month to fly to Illinois from United Kingdom, with most prices found around £488. If you aren’t able to travel to Illinois during the month of February, then flying in January is also cheap. Prices for this month can be found on momondo for an average of £538.

The cheapest day to depart on your flight to Illinois is on a Wednesday when prices can be found for as low as £679. This is often the case because there is less demand to fly during this day of the week. Flights from United Kingdom to Illinois on a Sunday will generally be more expensive and average around £724. Keep in mind that these prices on both days could fluctuate depending on the season and the demand.

Our data shows that the cheapest United Kingdom to Illinois flights are usually those with departure times at midday. Our users have found flights to Illinois at midday for as low as £659. In the afternoon is when there is more demand to fly to Illinois, so prices are often more expensive at around £705 per ticket.

Fly from London Heathrow to Chicago O'Hare Intl for the best United Kingdom - Illinois flight prices

You are more likely to see cheaper flights to Illinois from United Kingdom when booking weeks ahead of your departure date. In general, you can expect to find flights to Illinois for around £650 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 United Kingdom for as low as £596 on momondo.

There are 4 cabin classes available to choose from on United Kingdom to Illinois flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.

SWISS, Lufthansa, and United Airlines are the most popular carriers operating from United Kingdom to Illinois

British Airways, Aer Lingus and Icelandair are the top three most popular airlines that fly to Illinois from United Kingdom according to our data. British Airways is the first choice among our users, with 39% of people opting to fly with this airline when travelling to Illinois. Keep in mind that there are 17 different airlines that fly to Illinois on a routine basis, so you have a few additional options to choose from.

The number of flights available between United Kingdom and Illinois is 49 per day as of September 2026. The most frequent departure time is 11:00, with 51% of daily flights leaving at midday.

As of September 2026, 347 flights take off from United Kingdom and land in Illinois each week. The most common flight departure day for this route is Wed, with 16% of weekly flights taking off on this day.