Westpac Banking Corporation, more commonly known as Westpac, is an Australian bank and financial-services provider headquartered in Westpac Place, Sydney. It is one of Australias "big four" banks. Its name is a portmanteau of "Western-Pacific". As of November 2015, Westpac has 13.1 million customers, and is Australias largest branch network, with 1429 branches and a network of 3850 ATMs. The bank is Australias second-largest bank by assets. It is also the second-largest bank in New Zealand. On 29 January 2015, Bank South Pacific announced that it had entered into an agreement to acquire Westpacs banking operations in Samoa, Cook Islands, Solomon Islands, Vanuatu and Tonga for A$125 million.