Banks are rethinking how they use technology to deliver standout digital experiences and build stronger customer relationships. For decades, many institutions took pride in meeting new demands by heavily customizing their core systems, adapting them down to the smallest detail.

Today, banks are increasingly recognizing that customization is doing more harm than good. Legacy cores struggle to keep up with modern security standards and real-time decision-making.

Our own benchmark data with insights from over 200 banks, shows that nearly a third (28%) of legacy banking applications are undocumented, creating hidden operational risk and unnecessary uncertainty.

These challenges mirror broader industry findings that banks are under mounting pressure to modernize core technology foundations to support real-time data, AI driven decisioning, and operational resilience, rather than layering new capabilities onto aging systems.

At a time when technology is advancing fast, customer expectations are rising, and regulatory demands continue to evolve, hard coded customizations create brittle system dependencies. They introduce risk, stretch implementation timelines, and ultimately undermine a bank’s ability to compete.

Speed and agility are no longer differentiators; they are table stakes. Banks that free up capacity to invest in the “last mile”, where value is created closest to the customer, are the ones that will pull ahead.

Piecemeal customizations slow innovation

Constantly adapting core software to keep IT infrastructure running is expensive, time consuming, and complex. According to McKinsey, banking invests more in IT as a percentage of revenue than any other major industries. Typically ranging from about 6 to 12 percent of revenue.

Yet what begins as a way to stay aligned with customer needs often turns into long-term technical debt. Every customization adds another layer of complexity to the core, slowing integration and making change progressively harder.

Industry reports increasingly shows that banks are moving away from wholesale core replacement and instead modernizing progressively: retiring customizations, simplifying integration layers, and rebuilding around standardized, cloud native services.

When engineering teams are tied up managing legacy integrations, there is less capacity to develop new digital capabilities. Innovation slows, and banks fall into a cycle of reactive maintenance rather than proactive growth.

The SaaS advantage for modern banks

To launch and scale new solutions quickly, banks need to move away from fragmented customization toward powerful, unified integration. SaaS offers a faster path to value, delivering the benefits of cloud without the operational burden of managing infrastructure and upgrades.

Trusted vendors take responsibility for maintaining and evolving the core, while banks can safely configure proven solutions without hard coding changes that compromise stability.

This is the “adopt, don’t adapt” model in action. As SaaS, cloud native, composable core platforms are continuously maintained and enhanced through regular, managed updates. This delivers the resilience, scalability, and integration banks need. In contrast, some banks are still operating on core software not refreshed for a decade.

Just as importantly, standardized SaaS cores provide the clean data, consistent processes, and real-time integration required to embed generative and agentic AI directly into banking workflows. Not bolting intelligence onto fragmented legacy environments.

At the same time, financial institutions face relentless pressure to stand out, improve cost income ratios, and meet strict security, regulatory, and resilience requirements. When technology strategy and business strategy move together, banks can scale with confidence without sacrificing agility.

Value creation closer to the customer

A modern SaaS core is the foundation for better digital banking experiences. When core services run in the cloud, banks can move faster, innovate more confidently, and reduce operational disruption. The payoff is long-term resilience.

With that foundation in place, banks can focus on the last mile of value creation, the moments that matter most to customers. A modern core enables digital first experiences and hyper personalized offerings.

By using behavioral data and predictive insights, enabled by modern core and data architectures, banks can anticipate customer needs and surface relevant products at the right time.

A retail customer might receive a personalized investment recommendation based on recent spending patterns or life events. With customers holding an average of 2.59 products, the opportunity to deepen relationships through smarter, more intuitive interactions is significant.

A unified platform also gives banks a single, consistent view of the customer. That clarity allows institutions to deliver more seamless experiences and compete more effectively.

Rationalized decision making and measured customization

This shift away from hard coded customization does not mean customization disappears altogether. It means banks are being far more deliberate about when and how they do it.

With SaaS, the default is no longer to customize first. Instead, banks rationalize decisions, ensuring business needs are clearly defined and that any changes do not introduce new layers of complexity or long-term cost.

This shift aligns with wider industry analysis in recent Banking Technology Trends assessment with Bain & Company, which highlights simplification of the core, cloud-native SaaS adoption, and embedded intelligence as prerequisites for sustainable innovation.

Rather than endless adaptation, adopting modern software that is designed to be configured, extended, and evolved, allows banks to architect advantage and compete in today’s fast moving market.

In an environment where resilience, speed, and intelligence increasingly define competitiveness, adopting SaaS is less about technology preference and more about aligning with the direction banking itself is heading.

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Chief Technology Officer at Temenos.