London Heathrow Terminal 3 is a major hub primarily serving one world alliance members and several high-profile long-haul carriers. As of early 2026, the primary tenants include American Airlines, Delta Air Lines, Virgin Atlantic, and Emirates. Most British Airways short-haul and some long-haul flights also operate from T3, though their main base remains Terminal 5. Other significant airlines arriving here include Qantas, Cathay Pacific, Finnair, Japan Airlines (JAL), and LATAM. Terminal 3 is world-renowned for its collection of premium lounges, which are often considered some of the best in the global aviation industry. If you are arriving on an international flight at T3, you will find a modernized arrivals hall with integrated links to the Elizabeth Line, Heathrow Express, and the London Underground (Piccadilly Line). It is important to check your specific flight details before travel, as Heathrow frequently reshuffles airline terminal assignments to manage capacity, particularly for "fifth-freedom" flights and seasonal schedule changes.