US media reports that two threats made by a male caller proved unfounded.
The flight, carrying 206 passengers and 13 crew, landed at Newark Liberty International Airport at around 13:00 local time (17:00 GMT).
Passengers were evacuated from the plane and luggage removed. Police at the airport later said nothing harmful was found on board.
Customs officials continued checking the luggage but the aircraft was given the all-clear.
A spokesman for the Port Authority of New York and New Jersey, the airport's operator, said they had released the plane to British Airways.
Port Authority received the threat about the plane at around 10:00 local time (14:00 GMT), when it was already in the air.
ABC television reports that the two separate threats now appear to have come from the same person.
No arrests are reported to have been made and the investigation is ongoing.
A security alert over an unspecified threat to a British Airways flight from London to Newark has been lifted.