Commonwealth Bank has transitioned its entire core banking platform to AWS in one of the boldest technological changes in Australian banking. The project is expected to deliver improvements in speed, security and flexibility, though it also places a significant part of the national financial system under the management of a single cloud provider. CBA believes the shift will enable faster product rollouts, although it now routes around 40% of national banking transactions through AWS-operated data centres.
Previously, CBA ran core services such as deposits, loans and account management through its in-house infrastructure. The bank, which is already considered a technology leader in the local financial sector, finalised the migration just over a week ago following 18 months of preparation. While similar digital overhauls by other banks have been heavily publicised, CBA completed the transition quietly, focusing on speed and operational efficiency.
With the change, CBA can now implement product updates within weeks instead of months. Technical teams are also confident the upgrade will enhance stability. This was put to the test shortly after the shift, when a retail payments outage occurred. However, the issue was not directly tied to AWS. Customers are already experiencing quicker performance through digital banking, with basic tasks such as checking balances now nearly instant.
The move puts CBA further ahead in banking technology. Running core operations in the same environment as its data lake, which is also hosted on AWS, gives its AI systems faster and more accurate processing capabilities. The bank invests $2.3 billion each year in technology and views cloud adoption as key to enabling advanced features such as AI-powered tools that perform real-time banking tasks for customers.
Regulators continue to monitor the arrangement closely. CBA must ensure that all banking data remains in Australian-based AWS facilities and that there are no single points of failure. AWS operates multiple data centres across Australia, offering greater resilience compared to the Sydney mainframe CBA used previously. By the end of next year, CBA plans to move its final major legacy system, which supports credit cards, into the cloud.
