According to Wikipedia, in 2012 Terminal 3 handled 18.4 million passengers on 92,639 flights. 25% of the airport’s passengers, making it the second busiest terminal after Terminal 5 but only 20% of the airport’s flights, which is fewer than both Terminal 5 and Terminal 1.

Terminal 3 opened as The Oceanic Terminal on 13 November 1961 to handle flight departures for long-haul routes for foreign carriers to the United States, Asia and other far eastern destinations.

Airlines Destinations
American Airlines Charlotte, Chicago–O’Hare, Dallas/Fort Worth, Los Angeles, Miami, New York–JFK, Philadelphia, Raleigh/Durham
British Airways Accra, Barcelona, Bilbao, Budapest, Cape Town, Denver, Gibraltar, Hanover, Helsinki, Las Vegas, Lisbon, Luxembourg, Lyon, Marseille, Miami, Nairobi–Kenyatta, Phoenix, Prague, Vancouver, Vienna,Warsaw–Chopin
Cathay Pacific Hong Kong
Delta Air Lines Boston, New York–JFK
Emirates Dubai–International
Finnair Helsinki
Garuda Indonesia Jakarta
Iran Air Tehran–Imam Khomeini
Japan Airlines Tokyo–Haneda
Middle East Airlines Beirut
Oman Air Muscat
Pakistan International Airlines Islamabad, Karachi, Lahore
Qantas Dubai–International, Melbourne, Sydney
Royal Jordanian Amman–Queen Alia
SriLankan Airlines Colombo
TAM Airlines São Paulo–Guarulhos
Virgin Atlantic Atlanta, Boston, Delhi, Detroit, Dubai–International, Hong Kong, Johannesburg–Tambo, Lagos, Los Angeles, Miami, New York–JFK, Newark, San Francisco, Shanghai–Pudong, Washington–Dulles
Seasonal: Chicago–O’Hare
Vueling A Coruña, Barcelona

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