POSB Bank, simply known as POSB, is a Singaporean bank offering consumer banking services and is the oldest local bank in continuous operation in Singapore. Established on 1 January 1877 as the Post Office Savings Bank, the bank now operates as part of DBS Bank, which acquired the institution and its subsidiaries on 16 November 1998.Founded on 1 January 1877 as the Post Office Savings Bank (POSB), the bank was part of the Postal Services Department in the Straits Settlements and was set up by the colonial government to provide banking services for lower-income citizens.