Westpac is one of Australia’s oldest banks. It was established in 1817 as the Bank of New South Wales, the first lending institution in Australia. After a 1981 merger with the Commercial Bank of Australia, the new entity was renamed Westpac Banking Coorporation in 1982.

Westpac is the second largest bank in Australia by many measures. According to the Australian Prudential Regulation Authority (APRA), at the end of September 2023, Westpac along with CommBank were the two Australian banks with total residents' assets over $1 trillion apiece.

As of October 2023, it was the third largest by market capitalisation, behind CBA and NAB, at around $80 billion. In its 2023 annual report, Westpac said it had more than 36,000 employees. It also owns subsidiaries RAMS, St George Bank, BankSA, and Bank of Melbourne.

Westpac Group

Since 1982, the Westpac Banking Corporation (WBC) has expanded, acquiring several smaller Australian banks. Rate changes on loan and deposit products are often implemented in a similar fashion across all subsidiaries.

Bank of Melbourne

In 1997, WBC bought the operations of the Bank of Melbourne for $1.4 billion, along with the rights to its name and logo. In 2004, it was incorporated into the Westpac brand, but in 2011, a rebranded Bank of Melbourne was launched. Bank of Melbourne offers personal, business and corporate banking services,

St George Bank

In 2008, Westpac announced plans to merge with St George Bank, which at the time was the fifth largest bank in Australia, making up more than 30% of the new merged entity. The ACCC was satisfied the merger wasn’t likely to substantially lessen competition in Australian banking, and it went through in December '08. Banking services continue to be provided under the St George brand.

BankSA

Bank SA, formerly known as the Bank of South Australia, was acquired by Westpac in 2008. It continues to have South Australia’s largest network of branches and ATMs, with one in four South Australians using BankSA services.

RAMS

RAMS made waves in the 1990s and early 2000s for shaking up the mortgage market. Westpac acquired the brand in 2007. The brand used to offer banking products such as savings and transaction accounts, but has recently specialised in home lending, offering a broker service too.