Chicago London
BA, American, and United all fly nonstop from O'Hare to Heathrow. About eight hours going, closer to nine and a half coming home. All three compete hard on this route and fares stay close. Book the cheapest and don't overthink it. BA has the most departures, which matters if your plans change and you need to switch to an earlier or later flight.
One thing worth knowing: BA lands at Terminal 5, their home base. Immigration and bags move noticeably faster there than Terminal 2 (United) or Terminal 3 (American). If fares are within $50 of each other, that faster arrival is worth the difference.
Once you are through, the Elizabeth Line runs from Heathrow into central London in about 45 minutes. Tap your card at the platform, no ticket to buy. The Heathrow Express to Paddington is faster at 15 minutes but costs several times more. Skip the taxi unless someone else is paying.
Have a specific need? Use the decision guide below to filter by your airline, where you live, lounges, or where you're staying in London.
Pick What Matters to You
Best pair by where you're coming from
Best pair by where you're staying in London
Which pair your airline flies nonstop
| Airline | ORD–LHR |
|---|---|
| British Airways | ✓ |
| United Airlines | ✓ |
| American Airlines | ✓ |
Ranked by on-time performance
Lounge access by airport and terminal
Ranked by flights per week
Getting to the airport
Red-eye vs daytime departures
Premium cabin options
Connecting through Chicago from a domestic flight
Three carriers fly nonstop between O'Hare and Heathrow, with departures spread through the afternoon and evening. Adding a stop through another hub means three to five extra hours for savings that rarely justify the time.
If you are positioning from a smaller Midwestern city, O'Hare works well as a connecting point. Short domestic flights from across the region feed into the evening transatlantic departures. Build in at least two hours for the connection, especially if your domestic flight arrives at a different terminal than your London departure.
Chicago & London Airport Profiles
Each airport has a personality. Terminal quality, transit access, lounge scene, and crowd levels vary dramatically — sometimes more than the flight itself.
Chicago Metro
O'Hare has four terminals: Terminal 1, Terminal 2, Terminal 3, and the international Terminal 5. There is no Terminal 4. The terminals spread across a wide footprint connected by the ATS train and underground walkways. Allow 15 to 20 minutes to move between them.
Terminal 5 sits apart from the domestic terminals and handles most international flights. The ATS train connects it to the rest of the airport. Afternoon peaks bring longer security and immigration lines. The terminal is functional and recently updated, but smaller than the domestic concourses.
Terminals 1, 2, and 3 form the domestic core, with more dining and lounge options. The Blue Line train to downtown stops under Terminal 2, accessible from any terminal via the ATS.
London Metro
Heathrow has four active terminals and your airline determines which one you use. Terminal 5 is British Airways territory, the newest and most polished. Terminal 2, the Queen's Terminal, handles Star Alliance carriers. Terminal 3 has Virgin Atlantic and several US carriers. Terminal 4 is smaller and serves a mix of international airlines.
The terminals are not walkable between each other. Free inter-terminal transfers run on the Elizabeth Line or Heathrow Express between T2/T3 (which share a central area) and T5. T4 requires a separate bus. Build in 60 minutes if you need to change terminals for a connection.
Immigration at 6 to 8 AM is slow. The morning wave of transatlantic red-eyes all land in the same window, and queues back up. E-gates work for US passport holders, which helps, but the volume is real. The airport is well-signed and functional, not beautiful. Shopping is extensive if you clear customs early.
Gatwick has two terminals, North and South, connected by a free shuttle train that takes about two minutes. South Terminal is the larger of the two and handles most scheduled long-haul flights. North Terminal serves a mix of short-haul and charter carriers.
The airport is smaller than Heathrow and easier to navigate. Security queues are generally shorter except during summer holiday peaks. The walk from security to gates in South Terminal is short. The overall experience is less stressful than Heathrow, which is part of the appeal for budget travelers.
Gatwick sits 30 miles south of central London, roughly twice the distance of Heathrow. The Gatwick Express runs to Victoria in 30 minutes, which is competitive, but Victoria is not as well connected to east London as Paddington.
Stansted is a single-terminal airport designed by Norman Foster, and the building itself is worth noticing. The roof structure is a clean white canopy held up by trees of steel columns. It opened in 1991 and still looks modern. The terminal is compact and navigation is straightforward.
Stansted is a budget carrier hub. Ryanair dominates the departure boards. Long-haul service is limited. Most traffic is European short-haul on budget carriers. The airport does one thing well: move large numbers of passengers through a simple layout with short walking distances.
It sits 40 miles northeast of central London, the farthest of the four London airports from the city. The Stansted Express runs to Liverpool Street in 47 minutes, which is reasonable, but you are starting from much farther out.
Luton is a single-terminal airport 35 miles north of central London that has been undergoing expansion. The DART people-mover opened in 2023, replacing the old shuttle bus from the Luton Airport Parkway rail station. That shuttle bus was always the weakest link in getting to central London from Luton, and the DART fixes it.
The terminal is compact and functional. It serves mostly budget carriers on European routes. Any transatlantic service from New York is rare and seasonal. The airport handles fewer passengers than Heathrow, Gatwick, or Stansted, and it shows in the smaller food and retail options.
Luton works well for travelers headed to the north side of London, Bedfordshire, or the Midlands. For everyone else, the distance to central London and the limited flight options make it primarily a budget carrier airport.
London Southend is a small regional airport in Essex with a train station attached directly to the terminal building. The terminal handles a limited number of routes. Security queues rarely take more than 10 minutes, and the walk from the entrance to the gate is short.
The departures area past security has a few shops and food outlets. Do not expect the range of a larger airport. What Southend offers is speed: if you live nearby, you can leave home an hour before departure and make the flight.
London City Airport is the smallest of London's six airports, sitting in the Royal Docks between Canary Wharf and the Thames Barrier. The terminal is compact: one security area leads to a small departures lounge with views of the runway. You can arrive 30 minutes before a domestic flight and make it comfortably.
The runway is short, which limits the airport to smaller aircraft types. The approach is steep, which some passengers notice on landing. The upside of the small scale: no long walks to gates, no terminal train, no maze of corridors. A small selection of restaurants and shops sits airside.
Which Airlines Fly Which Pairs
Not all planes are the same size. The aircraft type below each checkmark tells you whether you are getting a widebody (777, 787, A350) with wider seats and a quieter ride, or a narrowbody (737, A321) with a single aisle. On flights over five hours, the difference is significant.
787-9
777-200, 777-300ER
767-300