How China Merchants Bank Completed Full Cloud Migration and Cut Costs

In an interview with 21st Century Economic Report, China Merchants Bank (CMB) Chief Information Officer Jiang Chaoyang said the future technology trend is open systems, emphasizing the move to distributed cloud architectures.

CMB announced that its "cloud migration" project is complete, moving debit card accounts, credit card customers, corporate accounts, and all branch applications to the cloud, making it the first of the top seven system‑important banks in China to achieve full cloud adoption.

While cloud adoption poses challenges for commercial banks—requiring stable IT systems and higher full‑stack cloud operations costs—the benefits are evident, prompting banks to adopt varied migration paths.

Other major banks have also advanced: Industrial and Commercial Bank of China leads with over 150 billion daily service calls; Agricultural Bank’s cloudization rate reaches 91%; Postal Savings Bank has deployed private cloud for 190 retail systems; CITIC Bank’s infrastructure cloudization is 99.7%; Ping An Bank exceeds 90% in both infrastructure cloudization and automation; China Everbright Bank’s business applications approach a 90% cloud rate.

Since early 2020, CMB’s cloud project, led by the headquarters IT department and involving over 22 business units, has rewritten 2.35 billion lines of code, fully reconstructing its account and application structures and upgrading the "Digital CMB" platform.

The migration timeline includes: host cloud launch in January 2020, core accounting go‑live in December 2020, debit account and customer data clouded in June 2022, credit card systems in September 2022, and corporate core services in December 2022.

CMB built an advanced cloud platform to host its most critical systems, handling over 2,220 applications, 200 k containers, 100 k virtual machines, 16 PB of data, and processing roughly 300 billion transactions daily.

The "super project" involved 20‑30% of CMB’s technology workforce, about 3 000 staff, and resulted in a 2.35 billion‑line codebase.

Regulatory pressure accelerated the shift: the 2016 IOE architecture became insufficient for high‑concurrency mobile internet demands, and the 2020 regulatory mandate required major information systems to migrate to cloud architectures with at least 60% migration.

Cost and efficiency gains are significant: cloud adoption supports more applications while dramatically lowering unit compute costs. For example, CMB’s credit‑card business saved roughly 60% in operating costs and achieved a ten‑fold increase in compute performance after moving to the cloud.

Although total IT spend remains stable, the cost structure changes: infrastructure costs did not rise linearly with increased cloud usage, and the proportion of technology expenses allocated to hardware and software procurement fell by about half, allowing more investment in application development.

Bank cloud migration follows two paths: a lift‑and‑shift approach that converts existing host workloads to cloud VMs or containers with minimal changes, and a full digital‑bank reconstruction that rewrites business code on IaaS/PaaS foundations to create a new middle‑tier supporting emerging services.

CMB chose the latter, establishing both a technology middle platform and a data middle platform. The technology middle platform consolidates over 4 600 functional components accessed via more than 26 000 APIs, reducing duplicate development. The data middle platform provides unified data asset access, analytics, and a machine‑learning platform, improving data governance and enabling faster problem resolution.

Looking ahead, CMB aims to transition from "On Cloud" to "In Cloud," fully unleashing cloud productivity to accelerate the "Digital CMB" initiative.