London Heathrow (LHR) is the busiest airport in Europe by international passenger traffic and one of the most connected globally — over 220 non-stop destinations, with particularly strong reach to North America, Asia, and the Middle East. It's British Airways' main hub and a cornerstone of the oneworld alliance.
Heathrow's strengths
Long-haul depth. LHR runs more transatlantic flights than any other European airport, with multiple daily frequencies to a dozen US cities. India and Southeast Asia are also unusually well-served. If you're flying premium cabin long-haul, the variety of carriers and aircraft types out of LHR is hard to match.
Terminals at a glance
- Terminal 2 — Star Alliance home base. Modern, well-laid-out.
- Terminal 3 — oneworld partners (American, Cathay, Qantas, etc.) and several non-aligned carriers.
- Terminal 4 — SkyTeam and other international carriers. A bit further from the central area.
- Terminal 5 — British Airways' main terminal, including most BA long-haul.
The honest reality
Heathrow runs near capacity, which means delays propagate fast and connections are tighter than the official minimums suggest. Allow 90 minutes for inter-terminal connections, longer if you need to clear immigration. The Heathrow Express to Paddington is fast and reliable but expensive; the Elizabeth Line is now the better value option for most travelers.
Visa transit reminder
LHR offers airside transit for most nationalities, but rules differ from other UK arrivals. If your itinerary includes a terminal change, make sure your transit visa requirements are clear — same-terminal transit is usually airside-only and doesn't trigger UK visa requirements.