Cheap flights from London Heathrow Airport to Chicago from $457

The month of September is, on average, the cheapest month to fly to Chicago from London Heathrow Airport, with most prices found around $594. If you’re not able to fly to Chicago in September, then February is your next best option. Flight prices from London Heathrow Airport to Chicago during February average around $617.

The cheapest day to depart on your flight to Chicago is on a Wednesday when prices can be found for as low as $783. This is often the case because there is less demand to fly during this day of the week. When flying out on a Monday, the most expensive travel day of the week, you can expect to see flight prices from London Heathrow Airport to Chicago for around $891.

Our most recent data shows that the best time of day to fly to Chicago is in the morning. Flights from London Heathrow Airport to Chicago during this time can be as low as $828. In contrast, the most expensive time of day to depart to Chicago is in the afternoon when prices are around $959.

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

You are more likely to see cheaper flights to Chicago from London Heathrow Airport when booking weeks ahead of your departure date. In general, you can expect to find flights to Chicago for around $739 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Chicago from London Heathrow Airport for as low as $690 on momondo.

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

No. A direct flight is the cheapest option for a flight between London Heathrow Airport to Chicago.

As of March 2026, prices for London Heathrow Airport to Chicago flights are approximately 12% more expensive when compared to flights at the same time last year.

Finnair, Icelandair, and Austrian Airlines are the most popular carriers operating from London Heathrow to Chicago

British Airways, American Airlines and Aer Lingus are the top three most popular airlines that fly to Chicago from London Heathrow Airport according to our data. British Airways is the first choice among our users, with 54% of people opting to fly with this airline when traveling to Chicago. Keep in mind that there are 9 different airlines that fly to Chicago on a routine basis, so you have a few additional options to choose from.

Historically, on average around 11% of flights between London and Chicago have experienced a delay on any given week. The average delay length over the past 12 months has been 169 minutes.

Generally, flights departing at night tend to experience fewer delays. Flights in the evening have, in the past, seen delays more frequently in comparison.

Thursday is statistically the day of the week which experiences the fewest number of delays on this flight route. Friday has historically seen more delays on average compared to the rest of the week.

According to our data, United Airlines have had the least number of delays on this route over the last 12 months; with about 5% of their flights experiencing any sort of delay.

Dublin (DUB) was the most common stop: 75% of momondo users choosing 1-stop flights on this route connected there.

Flights via Newark (EWR) offer the lowest average round-trip price of $688.

Flights connecting via Dublin (DUB) have the shortest average one-way travel time: 11h 27m.

Dublin (DUB) has the shortest average layover time for this route: 1h 30m.

The number of flights available between London Heathrow Airport and Chicago is 32 per day as of March 2026. The most frequent departure time is 12:00PM, with 65% of daily flights leaving in the afternoon.

The number of flights available between London Heathrow Airport and Chicago is 227 per week as of March 2026. The most frequent departure day is Wed, with 19% of weekly flights leaving on this day.