The origins of the Commonwealth Bank Group lie in the former Commonwealth Bank of Australia, which was created in 1911 by an Act of Parliament.

This Act established the Bank as a statutory corporation to conduct commercial and savings banking business. Its functions were later expanded to encompass those of a central bank.

Subsequent legislative amendment in 1959 created a separate Reserve Bank of Australia to take over the central bank functions.

In December 1990, the Commonwealth Banks Restructuring Act 1990 was passed, which provided for:

• the conversion of Commonwealth Bank into a public company with a share capital, governed by its Memorandum and Articles of Association but subject to certain overriding provisions of the Commonwealth Banks Act 1959 - this conversion occurring on 17 April 1991;
• Commonwealth Bank to become the successor in law of the State Bank of Victoria (SBV) - this occurring on 1 January 1991; and
• the issue of shares in the Commonwealth Bank to the public.

In July 1991 an offer of just under 30 percent of the issued shares in Commonwealth Bank was made to members of the Australian public and staff of Commonwealth Bank.  This was intended to strengthen Commonwealth Bank's capital base following its acquisition of SBV and to provide a sound foundation for further development of Commonwealth Bank's business. On 12 September 1991, 230 million shares were issued at an issue price of $5.40.

In October 1993, the Commonwealth Government sold a portion of its shareholding in Commonwealth Bank, thereby reducing its shareholding to 50.4 percent of the total number of issued voting shares. 178 million shares were listed on 1 November 1993, at an issue price of $9.35 for retail investors and $9.60 for institutional investors.

In June 1996, the Commonwealth Government sold its remaining 50.4 per cent shareholding in the Commonwealth Bank. The public offer component was fully subscribed.

In conjunction with this offer, Commonwealth Bank, pursuant to a buy-back agreement between Commonwealth Bank and the Commonwealth Government, agreed to buy back 100 million shares in Commonwealth Bank from the Commonwealth Government. The public offer and buy-back were completed on 22 July 1996.

The Government's public offer was for 399 million shares. Investors paid $6, with the remaining instalment of $4.45 being due on 14 November 1997. Investors were entitled to the three dividends payable in the intervening period.

Since privatisation was finalised in 1997, the Bank has extended its presence both nationally and overseas. In May 1989 the Bank purchased 75 per cent of New Zealand based ASB Bank Limited. On the 22nd of August 2000 the Group moved to gain full ownership of ASB Bank and purchased the remaining 25%.

On the 13th of June 2000, the Commonwealth Bank acquired 100% of the share Capital of Colonial Limited, a life insurance, banking and funds management group.

Today the Commonwealth Bank Group is a fully integrated financial services business. Providing a wide range of services, including retail, business, investment banking, broking services, insurance, finance company activities and funds management.