East Africa’s banking sector sits at a fascinating inflection point. On one side, millions of customers who have leapfrogged traditional banking entirely through mobile money — comfortable transacting via phone but with limited experience of formal banking products. On the other, legacy core banking systems built in the 1990s and early 2000s that were never designed for the API-first, real-time world customers now expect.

The Core Banking Modernisation Imperative

The central transformation challenge for most East African banks is the core banking system. These platforms — often Oracle Flexcube, Temenos T24, or custom-built mainframe applications — were architected for batch processing in an era when transactions settled overnight. Today’s requirements are fundamentally different: real-time processing, open APIs for fintech integration, mobile-native user experiences, and sub-second response times at scale.

Full core banking replacement is a KES 500 million to KES 2 billion exercise that takes three to five years. Most banks are instead pursuing a strangler fig pattern — wrapping the legacy core in a modern API layer, building new capabilities on modern infrastructure alongside the legacy system, and gradually migrating workloads until the legacy system handles only the most stable, high-volume transactions.

The Fintech Partnership Opportunity

The most progressive banks in the region have stopped viewing fintechs as competitors and started treating them as distribution and product partners. Open banking APIs, co-branded lending products, and Banking-as-a-Service (BaaS) infrastructure are enabling banks to reach customer segments they could never serve profitably through branch networks alone.

Digital transformation in East African banking is not simply about technology — it is about reimagining the value chain. The banks that emerge strongest will be those that use technology to make banking simpler, more accessible, and more relevant to the daily economic lives of their customers.