All branch staff and dealers within the business and equipment finance units will now be using Sovereign, an application provided by New Zealand-based Finzsoft.
Later this year the automobile financing system will be converted to run the Sovereign application.
According to a St George spokesperson, the bank is moving away from a mainframe environment, because it is "past its use-by date".
The spokesperson could not confirm what the bank was moving towards using as a backbone upon implementation of Sovereign.
St George Bank CIO, John Loebenstein, said the rollout of Sovereign is a major project, and Finzsoft was chosen after a review of other suppliers in the market.