Minna Bank’s Cloud-First Core System Powers MUFG’s New Digital Bank

Japan’s first digital bank, Minna Bank, achieves a landmark milestone as its cloud-native core banking system is adopted externally for the first time—by industry giant MUFG Bank

Key Highlights:

• Minna Bank’s fully cloud-based core banking system to be deployed by MUFG Bank’s new digital bank.
• Developed by Zerobank Design Factory (ZDF), in collaboration with Accenture and hosted on Google Cloud.
• First external provision of the system, marking a strategic shift in Japan’s digital banking infrastructure.
• A modular, microservices architecture designed to boost efficiency, scale, and rapid deployment.
• System leverages Google Kubernetes Engine, Spanner, and Vertex AI for scalability and intelligent insights.
• Minna Bank’s digital model serves over 1.3 million customers since its 2021 launch.
• Strategic aim: to empower financial and non-financial organizations globally with next-gen banking infrastructure.

In a transformative move for Japan’s digital banking landscape, Minna Bank announced that its pioneering cloud-based core banking system, developed by its technology subsidiary Zerobank Design Factory (ZDF), has been selected by MUFG Bank for its newly established digital bank. This marks the first instance of the platform—built on Google Cloud and co-developed with Accenture—being extended beyond Minna Bank’s own operations.

This milestone represents not just a commercial collaboration between two financial giants, but a signal of the growing demand for agile, cloud-native banking systems designed from the ground up to meet the evolving needs of both customers and institutions.

Minna Bank, a subsidiary of Fukuoka Financial Group, launched operations in May 2021 as Japan’s first fully digital bank. With more than 1.3 million accounts already under its fold, the bank has steadily evolved its technology stack to support not only its own consumer banking services (B2C), but also a wide range of B2B2X functions through APIs, and most significantly, the provision of its banking system as a standalone business offering.

Developed by ZDF, the core system is based entirely on cloud infrastructure, combining the power of microservices architecture, DevSecOps, and modular scalability. The technology foundation is built on Google Cloud, utilizing cutting-edge components like Google Kubernetes Engine for dynamic scaling, Spanner for global consistency in data handling, and Vertex AI for real-time analytics and intelligent service delivery.

According to Masashi Nakano, Senior Managing Director at Accenture Asia Pacific and Japan, the shift to cloud-native systems addresses a long-standing bottleneck in Japanese financial institutions: legacy system inefficiencies and rising operational costs. He emphasized the transformational capability of Minna Bank’s architecture in delivering “speed, modularity, and operational excellence” through a versatile platform capable of seamless integration with both new and existing ecosystems.

Toby Brown, Global Managing Director for Regulated Industries at Google Cloud, echoed this sentiment, noting that Minna Bank’s implementation offers a “blueprint for the future of digital transformation across industries.” He emphasized that the technologies employed are not only ideal for banking but also for broader sectors like retail and mobility looking to embed financial services into their platforms.

Leading this initiative from within is Kenichi Nagayoshi, President and CEO of both ZDF and Minna Bank. In a statement, he described the system’s external deployment as “a valuable milestone,” underscoring the potential for Minna Bank’s technology to foster global digital banking expansion. He added, “While we continue to evolve our offerings, our aim is to contribute—however modestly—to the international growth of digital banking.”

For MUFG Bank, one of Japan’s largest financial institutions and part of the Mitsubishi UFJ Financial Group, the decision to adopt a third-party, cloud-native system is a bold endorsement of digital-first innovation. The move suggests a strategic pivot in how large-scale traditional banks can operate with startup-like agility by partnering with lean, cloud-native providers.

This collaboration also strengthens the reputation of Fukuoka Financial Group, the parent company of both ZDF and Minna Bank, which has been aggressively pursuing digital transformation (DX) strategies. Established in 2007, FFG is Japan’s largest regional financial group and has positioned Minna Bank as a key pillar in its digital future.

Importantly, ZDF’s system has been designed for wide applicability beyond the banking sector. According to Accenture, the modular system can be employed by non-financial enterprises entering the embedded finance space—such as e-commerce, mobility, or fintech startups—making it a potent solution for future-ready platforms worldwide.

ZDF had first announced its ambition to offer its system to external entities—both domestic and global—in 2022. This announcement with MUFG represents the first realized deployment and could pave the way for further integrations across Asia and beyond.

As the lines between financial and non-financial services continue to blur, and as regulatory environments gradually accommodate digital banks and embedded finance models, cloud-native core banking systems like ZDF’s are emerging as the architecture of choice.

The successful provisioning of Minna Bank’s system to MUFG also illustrates how collaborative ecosystems—such as those between banks, cloud providers, and consultancies—can achieve more than siloed innovation. Together, Minna Bank, ZDF, Accenture, and Google Cloud have shown what’s possible when legacy limitations are shed in favor of cloud-first, customer-centric approaches.

With this expansion, Minna Bank is no longer just a trailblazer in Japan’s banking sector. It is now positioned as a platform pioneer, enabling financial transformation not just for itself, but for the industry at large.

About the Organizations:

Minna Bank is Japan’s first full-fledged digital bank, launched in May 2021 by the Fukuoka Financial Group. It aims to deliver “valuable connections for everyone” through innovative financial services and open API ecosystems.
https://corporate.minna-no-ginko.com

Zerobank Design Factory (ZDF) is a wholly-owned subsidiary of FFG and the developer of Minna Bank’s core cloud system. It is the first in Japan to architect such a system on a public cloud platform.
https://www.zdf.jp/en/

Fukuoka Financial Group (FFG) is Japan’s largest regional financial group and an early mover in banking digital transformation.
https://www.fukuoka-fg.com/en/