Royal Caribbean International has entered into an agreement with Meyer Werft in Germany to order a fourth Quantum-class ship for delivery in 2019.
The company already has Quantum of the Seas and Anthem of the Seas and a third Quantum-class ship, Ovation of the Seas, is under construction and is set to join the fleet next year.
The cruise line did not reveal where the fourth ship will sail.
Quantum and Ovation will be based in China while Anthem has just begun its maiden season sailing the Mediterranean from Southampton before it will move to New York.
"Today’s announcement is a reflection of the success of the first two Quantum-class ships," said Richard D. Fain, Royal Caribbean chairman and CEO.
"We have received a remarkable response from travel agent partners and travellers, and are thrilled that we’ll be able to deliver another revolutionary ship with our partners at Meyer Werft."
This means capacity increases for 2015, 2016, 2017, 2018 and 2019 are expected to be 5.5%, 6.3%, 3.1%, 3.9% and 6.5%, respectively.
"These figures do not include potential ship sales or additions that the company may elect to make in the future," said RCI in a statement.
The order is contingent upon the completion of customary conditions, including financing.
