Flight time from London to Chicago

How long is the flight from London to Chicago?

Counting only time in the air, London to Chicago is about 8h 48m non-stop. That figure comes from the 6,353-kilometre great-circle distance, the shortest line over the curve of the Earth, stretched by a small margin for real routing and divided by typical jet cruise speed, with taxi, climb, and descent folded in. On a real schedule the block time can run longer or shorter: headwinds, air-traffic routing, and the specific aircraft all move the number. The westbound leg of a long route into prevailing winds is often the slower of the two directions.

Time difference between London and Chicago

Chicago is 6 hours behind London (-06:00 relative to the origin). Flying westbound, that offset hides part of the apparent trip length: the 8h 48m you spend in the air looks shorter on the arrival clock. When the wheels touch down, your body is still on London time, which is exactly the figure the live calculator below shows as the body-clock reading. The gap can shift by an hour around daylight saving transitions, since the two regions rarely change their clocks on the same weekend.

Jet lag on this route

Crossing 6 time zones westbound is enough to feel. As a rule of thumb the body re-syncs about one time zone per day, so plan for a few days of adjustment. Westbound travel, gaining hours, staying up later, is usually the gentler direction. Get evening light at the destination and try to hold off sleep until a local bedtime. For a personalised light, sleep, and meal plan, see the jet lag calculator.

Distance and the great-circle path

The 6,353 km figure is the great-circle distance, computed with the haversine formula between the two city coordinates. On a flat map it can look like a curve, because the shortest real-world path bows toward the pole rather than following a straight line of latitude, which is why London-Chicago flights often track far north or south of where the map suggests. Real flown distance is a touch longer, around 6,734 km here, once airways and weather routing are added. To unwind the time-zone math on your own specific flight, enter the boarding-pass times below.