Cheap flights from Chicago O'Hare Intl Airport to London from $434

The month of January is, on average, the cheapest month to fly to London Heathrow Airport from Chicago O'Hare Intl Airport, with most prices found around $642. If you’re not able to fly to London Heathrow Airport in January, then November is your next best option. Flight prices from Chicago O'Hare Intl Airport to London Heathrow Airport during November average around $686.

Our data shows that Tuesday is the least expensive day to fly to London Heathrow Airport. Tickets to fly out on this day can be as low as $787. The most expensive day to fly to London Heathrow Airport is Saturday, with ticket prices averaging around $989.

According to our data, the cheapest time of day to fly to London Heathrow Airport is in the evening. momondo users have found flights departing from Chicago O'Hare Intl Airport to London Heathrow Airport in the evening for as low as $859. Keep in mind that these prices may fluctuate based on what airline you choose and the time of year you plan to travel. Flights in the afternoon are often more expensive with an average ticket price of $873.

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

You are more likely to see cheaper flights to London Heathrow Airport from Chicago O'Hare Intl Airport when booking weeks ahead of your departure date. In general, you can expect to find flights to London Heathrow Airport for around $805 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to London Heathrow Airport from Chicago O'Hare Intl Airport for as low as $698 on momondo.

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

As of May 2026, prices for Chicago O'Hare Intl Airport to London Heathrow Airport flights are approximately 8% more expensive when compared to flights at the same time last year.

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

British Airways, American Airlines and United Airlines are the top three most popular airlines that fly to London Heathrow Airport from Chicago O'Hare Intl Airport according to our data. British Airways is the first choice among our users, with 52% of people opting to fly with this airline when traveling to London Heathrow Airport. Keep in mind that there are 16 different airlines that fly to London Heathrow Airport on a routine basis, so you have a few additional options to choose from.

Historically, on average around 25% of flights between Chicago and London have experienced a delay on any given week. The average delay length over the past 12 months has been 174 minutes.

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

Tuesday is statistically the day of the week which experiences the fewest number of delays on this flight route. Sunday 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 25% of their flights experiencing any sort of delay.

Reykjavik (KEF) was the most common stop: 46% of momondo users choosing 1-stop flights on this route connected there.

Flights via Munich (MUC) offer the lowest average round-trip price of $591.

Flights connecting via Dublin (DUB) have the shortest average one-way travel time: 10h 16m.

Dublin (DUB) has the shortest average layover time for this route: 1h 33m.

As of May 2026, 57 flights take off from Chicago O'Hare Intl Airport and land in London Heathrow Airport each day. The most common flight departure time for this route is 5:00PM, with 67% of daily flights taking off in the evening.

As of May 2026, 404 flights take off from Chicago O'Hare Intl Airport 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.