Cheap flights from London Heathrow Airport to Chicago from £346

The cheapest month to fly to Chicago O'Hare Intl Airport from London Heathrow Airport is in February. Flight prices, which tend to average around £472, are often lower during this time because this is during the off-season. If you aren’t able to travel during the month of February, then book flights to Chicago O'Hare Intl Airport from London Heathrow Airport during January instead. Flights to Chicago O'Hare Intl Airport in January, while not as cheap as those in February, still average around £538.

The cheapest day to depart from London Heathrow Airport to Chicago O'Hare Intl Airport is on a Wednesday. Travellers who choose to depart for Chicago O'Hare Intl Airport on a Wednesday will often find tickets for as low as £679. 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 Chicago O'Hare Intl Airport on Sunday is £724.

The cheapest time of day to fly to Chicago O'Hare Intl Airport is at midday when flights can be purchased for as low as £658. In contrast, the most expensive time of day to depart to Chicago O'Hare Intl Airport is in the afternoon when prices are around £705.

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

You are more likely to see cheaper flights to Chicago O'Hare Intl Airport from London Heathrow Airport when booking weeks ahead of your departure date. In general, you can expect to find flights to Chicago O'Hare Intl Airport 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 Chicago O'Hare Intl Airport from London Heathrow Airport for as low as £596 on momondo.

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

SWISS, Austrian Airlines, and United Airlines are the most popular carriers operating from London Heathrow to Chicago O'Hare Intl

British Airways, Lufthansa and Icelandair are the top three most popular airlines that fly to Chicago O'Hare Intl Airport from London Heathrow Airport according to our data. British Airways is the first choice among our users, with 61% of people opting to fly with this airline when travelling to Chicago O'Hare Intl Airport. Keep in mind that there are 14 different airlines that fly to Chicago O'Hare Intl Airport on a routine basis, so you have a few additional options to choose from.

Historically, on average around 10% 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 181 minutes.

Generally, flights departing in the morning tend to experience fewer delays. Flights departing in the early afternoon have, in the past, seen delays more frequently in comparison.

Monday is statistically the day of the week that experiences the fewest delays on this flight route. Tuesday has historically seen more delays on average compared to the rest of the week.

According to our data, United Airlines have had the fewest delays on this route over the last 12 months, with about 6% of their flights experiencing any sort of delay.

Reykjavik (KEF) was the most common stop: 40% of momondo users choosing one-stop flights on this route connected there.

Flights via Copenhagen (CPH) offer the lowest average return price of £453.

Flights connecting via Dublin (DUB) have the shortest average one-way travel time: 11h 59m.

Zurich (ZRH) has the shortest average stopover time for this route: 1h 13m.

The number of flights available between London Heathrow Airport and Chicago O'Hare Intl Airport is 27 per day as of September 2026. The most frequent departure time is 11:00, with 51% of daily flights leaving in the afternoon.

195 flights are operational weekly from London Heathrow Airport to Chicago O'Hare Intl Airport as of September 2026. The most popular departure day for this route is Mon, with 25% of flights per week taking off on this day.