Cheap flights from Chicago to the United Kingdom from $145

In general, October is the cheapest month to fly from Chicago to United Kingdom. Due to it being the ‘off-season’ during this time, you can expect flight prices to be around $639. If you aren’t able to travel to United Kingdom during the month of October, then flying in January is also cheap. Prices for this month can be found on momondo for an average of $700.

The cheapest day to depart from Chicago to United Kingdom is on a Tuesday when prices can be found for as low as $807. The most expensive day to fly to United Kingdom is Saturday, with ticket prices averaging around $1,031.

According to our data, the cheapest time of day to fly to United Kingdom is in the evening. momondo users have found flights departing from Chicago to United Kingdom in the evening for as low as $916. Keep in mind that these prices may fluctuate based on what airline you choose and the time of year you plan to travel. Flights to United Kingdom are more costly in the afternoon, with an average ticket price of $918. Departure times in the afternoon fall within the peak daily travel times, which is why tickets can be more expensive.

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

You are more likely to see cheaper flights to United Kingdom from Chicago when booking weeks ahead of your departure date. In general, you can expect to find flights to United Kingdom for around $818 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to United Kingdom from Chicago for as low as $745 on momondo.

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

Virgin Atlantic, Icelandair, and British Airways are the most popular carriers operating from Chicago to United Kingdom

British Airways, United Airlines and Aer Lingus are the top three most popular airlines that fly to United Kingdom from Chicago according to our data. British Airways is the first choice among our users, with 38% of people opting to fly with this airline when traveling to United Kingdom. Keep in mind that there are 17 different airlines that fly to United Kingdom on a routine basis, so you have a few additional options to choose from.

Historically, on average around 25% of flights between Chicago and United Kingdom have experienced a delay on any given week. The average delay length over the past 12 months has been 173 minutes.

Generally, flights departing in the early afternoon tend to experience fewer delays. Flights in the morning 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, British Airways have had the least number of delays on this route over the last 12 months; with about 24% of their flights experiencing any sort of delay.

As of June 2026, 57 flights take off from Chicago and land in United Kingdom each day. The most common flight departure time for this route is 6:00PM, with 79% of daily flights taking off in the evening.

The number of flights available between Chicago and United Kingdom is 399 per week as of June 2026. The most frequent departure day is Mon, with 15% of weekly flights leaving on this day.