Flights from Chicago to London
Goodtern scores every Chicago–London itinerary 0–100 against what you actually care about — price, time, stops, comfort, carbon — and shows the receipts for why #1 is #1.
Distance
6,345 km (3,943 mi)
Estimated non-stop time
~8h 8m
Usually cheapest
7–21 weeks before you fly
Route type
Long-haul
Distance is great-circle; flight time is a physics-based estimate, not a schedule. Booking guidance reflects typical fare patterns, not a price promise.
When to book
On long-haul routes like Chicago to London, fares typically bottom out 7–21 weeks before you fly, climb steeply in the final fortnight, and peak-season dates (summer holidays, Christmas and New Year, Easter) both cost more and sell out earlier. Goodtern's best-time-to-buy signal tracks this curve against your own search history and flags the moment a fare looks like a genuine deal.
Airports on this route
Frequently asked questions
How long is the flight from Chicago to London?
Non-stop, expect roughly 8h 8m in the air — an estimate based on the 6,345 km distance, not a schedule. Connecting itineraries take longer.
How far is London from Chicago?
About 6,345 km (3,943 miles) by great-circle distance — a long-haul route.
When is the cheapest time to book flights from Chicago to London?
For long-haul routes like this one, fares are typically at their lowest 7–21 weeks before you fly. That's a pattern, not a guarantee — peak dates (summer, Christmas) sell out earlier.
Which airports can I use for this route?
Served by O'Hare (ORD). Served by 5 airports: Heathrow (LHR), Gatwick (LGW), Stansted (STN), Luton (LTN), London City (LCY). Goodtern's nearby-airport search compares all of them automatically.