CASE STUDY Commonwealth Bank of Australia
Rewiring the heart of Australia’s largest Bank
How the Commonwealth Bank of Australia rebuilt the systems behind everyday banking, creating a resilient foundation for continuous change
5-MINUTE READ
Real-time banking has become the new performance frontier—and it is forcing a leadership decision. Institutions built on decades-old systems are finding that incremental upgrades can no longer deliver the speed, resilience and trust customers now expect.
For the Commonwealth Bank of Australia (CBA), which supports nearly 40% of Australia’s payments, the stakes were unusually high. At that scale, even small delays have large implications—across customers, operations, and the broader financial system.
The Bank chose a decisive path. Rather than extending its legacy systems, it set out to build a new foundation for everyday banking—one designed to evolve as needs and expectations change. From the start, it partnered with Accenture to help make the right trade-offs, manage risk safely, and reshape how teams run daily banking without interruption. Beyond the technology, success depended on tight leadership alignment and a shared operating model—allowing hundreds of teams to move in step while protecting critical banking services at scale.
Together, CBA and Accenture rebuilt the systems 17 million customers rely on, completing the transition with minimal customer disruption while keeping more than 70 million transactions running every day. As a result, the system now performs 30% faster, delivering a snappier real time experience today, and enabling more dynamic customer experiences tomorrow. At the same time, the Bank reduced daily operating costs by nearly 30%, freeing up capacity to reinvest in growth and innovation.
30%
faster balance and account updates
30%
reduction in daily operating costs
Built for change
Delivering on that decision required an approach structured for ongoing change. Working closely with Accenture, CBA established a cloud‑based platform built on SAP Transaction Banking (TRBK) on Amazon Web Services (AWS), delivering the scale and reliability required across balances, payments, and regulatory reporting. What followed was a disciplined approach to change—designed to modernize the core, manage risk, and keep critical banking services running reliably.
Replacing a mission‑critical core required partners we could trust. Accenture and AWS helped us modernise our SAP platform while preserving stability at scale.
Simon Davies / General Manager of Core Banking, Commonwealth Bank of Australia
Compounding returns
Reliability Australia can bank on
Today, processing more than 4,000 transactions per second, CBA operates one of the world’s largest real-time banking platforms, built for national-scale reliability. That agility accelerates the adoption of new payment standards and emerging technologies, strengthening the resilience of Australia’s financial ecosystem.
When a bank’s core processes millions of transactions every day, resilience isn’t optional. AWS is proud to support the foundation that helps CBA operate at scale.
Jamie Simon / Director, Financial Services Industry, ANZ, Amazon Web Services