In the early 20th century it established a presence in schools by setting up a special category of savings accounts for schoolchildren, and grew through the following decades.
Its sole employee was John Hector, who started the business a single room in Gawler Place, Adelaide, that was provided rent-free by the Glen Osmond Mining Company.
[citation needed] During the 26-year era of Liberal premier Thomas Playford (November 1938 – March 1965), the bank was a key tool of his vision for the state's rapid economic and industrial development.
McMichael was responsible for the design, after trustees and executives of the bank had visited Sydney and Melbourne to inspect the most modern buildings in those cities.
Significant to the Art Deco style are the motifs depicting South Australian agriculture, along with the use of parallel lines, the polished granite base and the monumental entrance.
However, Labor lost the 1979 election and Liberal premier David Tonkin (September 1979 – November 1982) would not allow the banks to merge.
The State Bank of SA failed because it had a "non-performing" loan portfolio, meaning that repayments were not made on money lent.