By Andy Sambidge
Flights to Cochin, Islamabad, Karachi, Lahore, Peshawar also move to Terminal 3.
Etihad Airways has been handed security approval to start US flights from the new terminal 3 at Abu Dhabi International Airport.
Passengers flying to Chicago and New York will now check-in and board from Terminal 3 after the airline won the green light to operate flights to US destinations from the new terminal.
Premium customers flying to the US can now access Etihad's First and Business class check-in and lounges in Terminal 3, news agency WAM reported.
In addition to the US destinations, flights to Cochin, Islamabad, Karachi, Lahore and Peshawar now operate from Terminal 3, switching from Terminal 1.
Flights to Colombo and Moscow will move to Terminal 1, the airline added.
Terminal 3 opened in January 2009, taking the airport to an approximate capacity of 12 million passengers per year.
It is expected that passenger numbers will reach this level in 2011.
Peter Baumgartner, Etihad Airways' chief commercial officer, said: "We are pleased to now be able to offer our US-bound customers the convenience and luxury of Terminal 3."