Whitepaper: NTT and AWS on Insurance Mainframe Modernisation

For insurers, the mainframe has long been a symbol of resilience. 

But, as rising costs, siloed data, and AI-driven competition reshape the market, the same systems that once protected the business are now making it harder to innovate quickly. 

That tension is the central message of NTT DATA’s new whitepaper called Mainframe modernization: Why insurers can’t afford to stand still – compiled in collaboration with AWS.

The report argues that modernisation does not have to mean a risky, all-or-nothing replacement. Instead, insurers can modernise selectively and incrementally, stabilising what must stay, decoupling what slows them down and moving the right workloads to cloud environments where flexibility, data access and AI-ready design can deliver faster value.

Jayme Hart, AWS Global Head of Insurance Industry Development, says in the whitepaper: “Insurance companies don’t have to choose between the reliability of their mainframes and the flexibility of the cloud. 

“With AWS and NTT DATA, they can modernise at their own pace – protecting the systems that keep their businesses running while opening the door to better data, smarter insights and innovation. 

“It’s about reducing risk, cutting complexity and turning core platforms into a foundation for growth.”

The importance of the issue

The report says that many insurers are still spending heavily just to maintain legacy systems, while customer expectations, regulatory pressure and cyber risk continue to rise. 

It also highlights how tightly coupled architectures, undocumented dependencies and shrinking mainframe skills pools can turn even small changes into long, expensive projects.

That is why the whitepaper frames modernisation as a business issue, not just a technical one. 

If insurers want faster product launches, better underwriting insight and more responsive claims handling, they need architectures that support real-time data and AI-enabled workflows.

Paving a pragmatic path forward

Rather than pushing a “big bang” replacement, NTT DATA and AWS advocate a phased approach that combines assessment, prioritisation and coexistence. 

In practice, that can mean keeping stable workloads on the mainframe while exposing data and functionality through APIs, migrating change-heavy applications to cloud and using automation and AI to reduce the risk and effort of refactoring.

The whitepaper also shows how cloud and AI change the economics of modernisation by making dependency mapping, code analysis and transformation more manageable than they were in the past. 

Alongside this, it is equally clear that technology alone is not enough: insurers still need deep domain expertise and disciplined governance to preserve policy data, business rules and regulatory confidence.

What NTT DATA and AWS bring

A key theme in the paper is that insurers do not need to choose between stability and agility. 

NTT DATA says its work with AWS helps clients modernise mainframe environments while protecting business continuity, reducing cost and creating the foundation for AI and analytics. 

The paper also claims joint projects have reduced mainframe operating costs by 50% to 80% and accelerated modernisation efforts by 30% to 50% using AI-supported delivery frameworks and accelerators.

One of the strongest proof points comes in the form of a customer example: a German multinational financial services and insurance provider modernised across four markets, moving large-scale workloads from legacy systems into AWS without disrupting operations. 

The whitepaper says that the programme is expected to cut annual operating expenses by more than 20% by 2028 and enable new products and capabilities to reach market around 30% faster.

The report combines strategic argument, operational guidance and real-world examples in one place for insurance leaders and is a must-read for those trying to balance resilience, cost control and speed to market while avoiding the classic pitfalls of disruptive core replacement programmes.