May 14, 2026

Core banking modernization: Key drivers, stages and benefits

Key takeaways

  • Core banking modernization is a matter of maintaining a competitive edge against digital attacker banks and fintech challengers.

  • Banks can modernize their systems by fully replacing them, replacing one component after another or launching a parallel next-generation core.

  • Core banking modernization involves assessing the system in place, defining goals, securing stakeholder alignment, choosing the approach, planning and implementing the solution.

 

How much does your core banking system cost you? Chances are, its general upkeep already eats up around 15% to 20% of the annual IT budget. Together with other “run-the-bank” activities, more than half of the tech spend goes toward keeping the lights on, while innovation inevitably takes a back seat.

In the meantime, banks’ digital-native rivals are snatching up much of the growth in financial services revenues. Unburdened by legacy systems, top performers among digital attacker banks have grown at a CAGR of 85%-100% over the past five years, compared with a mere 10%-15% among incumbents.

Issues with legacy core banking systems are nothing new. As of 2025, a stunning 98% of banks were planning to upgrade their core banking systems within three years. Their insufficient modularity, the number one constraint for innovation, is among the key drivers.

The question isn’t, “Do we need to modernize?”; we’re long past that. The question is, “How do we approach core banking modernization to get a good ROI out of it?”

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What core banking modernization is (and isn’t)

Before we get into answering this question, let’s brush up on the definitions. Core banking modernization involves upgrading or replacing core banking systems, infrastructure, and processes. Its goals may include:

  • Improving operational efficiency

  • Closing customer experience gaps

  • Enabling integration with modern technology solutions

  • Reducing upkeep costs

While digital transformation and modernization typically go hand in hand, they’re not the same. A digital transformation is a strategic undertaking that involves changing how the business functions and delivers value. For banks, modernization is typically one component of digital transformation, alongside revamping customer journeys, processes, and product offerings.

Why banks need core banking modernization

Core systems modernization isn’t optional anymore; it’s a matter of survival. Legacy systems simply come with too many drawbacks:

  • Every little change becomes a resource-intensive development task

  • Integrations with modern BaaS solutions and technologies can be near-impossible

  • Manual data entry remains the rule of the land, causing slow time-to-insight

  • High maintenance costs leave little budget for tech innovation

  • Outdated technologies entail substantial security risks

  • Closing customer experience gaps becomes an ordeal

  • Supporting basic functionality often requires expensive workarounds

Those drawbacks are undermining banks’ ability to compete. Fintech challengers and neobanks are successfully increasing their share of the wallet, making them a major threat to bank and credit union executives. Dissatisfied with digital experiences, consumers flock to them: 29% of them switch providers for this very reason.

Source: Cornerstone Advisors – What’s Going On in Banking 2025.

When done right, core banking platform modernization can have a positive ripple effect across an organization, from increased operational efficiency to reduced post-merger integration costs.

In a joint 2024 whitepaper, EY and FIS quantified the many benefits of modernization across four areas:

Source: EY – The New Rules of Core Modernization.

There are also other, qualitative benefits of core banking modernization:

  • Facilitated compliance

  • Mitigated security risks

  • Improved system agility and scalability

  • Better ability to innovate

…But inherent challenges and risks can undermine the ROI

While deciding to modernize is a no-brainer, reaping tangible benefits from the modernization of a banking system isn’t as straightforward. Only 49% of banks report significant improvement in customer experience post-modernization, with figures even lower for other outcome categories.

Paradoxically, 69% of banks reported increased risk management difficulties, and 63% said it became harder to maintain system resilience.

While reasons vary on a case-by-case basis, these challenges and risks are common culprits:

  • Migrating all data and workloads with as few interruptions as possible

  • Maintaining data security and compliance

  • Demonstrating long-term ROI to justify the initial investment

  • Overcoming the “we’re used to it” sentiment to secure stakeholder buy-in

  • Securing sufficient resources for modernization, including tech talent

Selecting the right path forward: Key modernization approaches

There are three main approaches to modernization, and the risk appetite and the condition of the existing system typically determine which approach is the most suitable.

Full replacement

If the legacy system is unsustainable and no longer meets business needs, fully replacing it with a new system could be a solution. But in the banking industry, it’s akin to an open-heart surgery considering the sheer scope of risks involved (data migration, downtime, etc.). It’s also usually the most expensive option on the table.

While full replacements are rare, they do happen. Case in point: Seattle Bank chose this very approach to modernize its core in 2019.

Component-based replacement

Under this approach, core system components progressively get replaced one by one. For example, a bank may replace a product module first, then the payment reconciliation and settlement system, then the risk and compliance management component.

It’s a less risky option; however, untangling the mess of the decades-old codebase to define components could be a time-consuming endeavor in its own right.

Wrapping or augmenting

This approach involves building a parallel core to support advanced functionality and connecting it to the legacy system via APIs. As a result, the bank effectively uses two core systems: one for legacy functions, the other for next-generation features.

This approach allows banks to retain legacy systems and avoid complete overhauls, thereby mitigating risks and reducing costs. The approach also preserves data and processes of the legacy system, removing migration risks from the equation. That said, orchestrating connections and maintaining multiple systems can be time-consuming and resource-intensive.

Extra consideration: Cloud adoption

Migrating to the cloud can be part of the equation regardless of the selected modernization approach.

Decommissioning on-prem infrastructure in favor of private or hybrid cloud not only reduces operational costs but also improves scalability, agility, and integration capabilities. Moreover, cloud is the foundation for cutting-edge capabilities like AI/ML predictive analytics.

That said, moving core systems to the cloud poses substantial security and compliance challenges, which is why banks are hesitant to migrate these workloads. Third-party risk management, as mandated by regulations such as DORA in the EU, also becomes more complex when cloud providers are added to the mix.

What it takes to modernize the core: 6 stages

Core banking modernization could be the most complex tech project in many banks’ history. Whether it’s a complete system overhaul or a component-by-component upgrade, it requires a comprehensive strategy and extensive planning, coordination, and investment. 

Assessing the existing core banking system

First, you need to understand where you stand with your current core banking system. To that end, evaluate it using four types of parameters:

  • Functional: alignment with business needs, performance, ease of integration with modern solutions

  • Financial: operating costs, cost-benefit implications of the migration

  • Technological: code complexity, system architecture, update difficulty, change request implementation time

  • Risk: Technology obsolescence risk, tech skill availability, potential disruptions, documentation gaps

Defining modernization goals

What do you want to achieve through modernization? Consider the goals for your business, technology and operations alike. Define KPIs for every goal you set.

Securing stakeholder alignment

Strong stakeholder alignment is another crucial ingredient of a successful core modernization initiative. It involves:

  • Ensuring business sponsorship and ownership

  • Devising a decision-making and governance framework

  • Securing the required resources, including talent

  • Preparing a change management strategy

  • Managing the business case to demonstrate tangible benefits

Selecting the modernization approach

Full replacement will be suitable for unsustainable legacy systems. Component-based replacement is less risky, even though it takes more time. Wrapping/augmenting, in turn, are usually good options for launching digital-only brands.

Planning the modernization

There’s a multitude of moving parts in the modernization of a banking system. On the technology side of it, you have to take into account:

  • Infrastructure design (cloud/on-premises/hybrid)

  • Application architecture (e.g., domain-driven design)

  • Integration architecture (APIs, data pipelines, etc.)

  • Development tools and methodologies (CI/CD, DevOps, agile)

Security, privacy, and organizational change management should also be at the forefront of your mind.

Executing and rolling out

Design and build new components or a parallel core, or prepare to migrate to a new core banking system. Make sure you have cutover and deployment plans in place to minimize disruptions and other risks. Post-rollout, monitor the system and continuously optimize its performance.

How DXC supports core banking modernization

Powered by 45+ years of experience in banking technology, DXC’s financial services technology solutions help banks transform their core banking systems to optimize costs, improve competitive positioning, and power CX excellence. We provide modernization-as-a-service that includes:

  • Legacy code analysis and conversion

  • Reengineering and SDLC modernization

  • Outcome-driven modernization with risk mitigation

Our deep technical expertise enables financial institutions like Leeds Building Society to move away from their legacy cores while mitigating risks. While DXC is the custodian of Hogan, our diverse global partner network also includes core banking providers like Temenos and Finastra.

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Frequently asked questions

Core banking modernization involves replacing or upgrading core banking systems, their underlying infrastructure, and related processes.

Banking modernization projects typically take several years to complete. That said, 94% of banking overhauls extend beyond their original timelines.

AI is gaining ground in automated fraud detection, CX hyper-personalization, and code modernization. Open banking APIs and distributed ledger technology (DLT) are also among emerging technology trends.