AS400 Learning Center

Is AS400 Still Used?

Yes. AS400 ... now called IBM i on IBM Power Systems ... is still actively used by thousands of organizations worldwide. IBM continues to invest in the platform with new hardware releases and OS updates.

Yes, AS400 is still used ... and heavily. IBM estimates that IBM i runs more than 7,000 applications and supports more than 15,000 ISVs worldwide. The platform operates in manufacturing plants, bank data centers, hospital systems, government agencies, and retail chains across every major market. The name changed. The workload did not go away.

How Many Companies Still Use AS400?

IBM estimates over 100,000 organizations worldwide run IBM i (the modern AS400). The United States has the largest installed base, followed by Germany, the United Kingdom, Canada, and Japan. Significant concentrations exist in manufacturing, financial services, healthcare, retail, and government sectors.

IBV data from 2023 indicates that IBM i clients show above-average retention rates compared to other midrange platforms. The economics of migration, the reliability of existing workloads, and the absence of a compelling alternative drive this retention.

Which Industries Still Run AS400?

AS400 and IBM i are most concentrated in industries where reliability, transaction volume, and data integrity are non-negotiable:

  • Manufacturing: JD Edwards, MAPICS, and other ERP systems that originated on AS400 remain in production
  • Financial services: Core banking systems, insurance policy administration, and credit union platforms built on IBM i
  • Healthcare: Patient record systems, billing platforms, and hospital information systems
  • Retail: Inventory management, POS backends, and distribution systems
  • Government: State and local government record management and financial systems

Is IBM Still Developing the AS400 Platform?

Yes. IBM has actively developed IBM i through multiple release cycles since the platform was renamed. IBM i 7.5 was released in April 2022. IBM has published a roadmap indicating continued development and support. IBM Power11 hardware, released in 2024, brings new performance capabilities to IBM i workloads.

IBM has also invested in modernization tools that allow IBM i environments to integrate with REST APIs, modern development frameworks, and cloud services, making the case for staying on the platform while modernizing the interface layer.

Why Do Organizations Stay on AS400?

Several economic and technical factors explain why organizations with AS400 environments often choose to stay rather than migrate:

  • Reliability: IBM i environments routinely run for years without unplanned downtime
  • Total cost of ownership: Stable platforms with no licensing model changes and no forced upgrades
  • Migration risk: Business-critical ERP, banking, or manufacturing systems carry enormous migration risk
  • Skills availability: Decades of institutional knowledge embedded in custom RPG code
  • Performance: IBM Power hardware delivers excellent transaction processing performance for database-heavy workloads

For many organizations, the question is not whether to leave AS400, but how to modernize the user experience and integration layer while preserving the stability of the core platform.

Frequently Asked Questions

Is AS400 still supported by IBM?
Yes. IBM i (the modern AS400) is actively supported. IBM i 7.3 is supported through April 2026, IBM i 7.4 through April 2028, and IBM i 7.5 through April 2030. IBM publishes official support dates on its website.
Is AS400 dying?
No evidence supports this. IBM continues to release new hardware (Power11 in 2024), new IBM i OS versions (7.5 in 2022), and new tools for modernization. The installed base remains large. Organizations that predict AS400's death have been making that prediction for 30 years.
What is the difference between AS400 still running and AS400 being relevant?
AS400 environments are still running because they host critical workloads that organizations depend on. They are relevant because IBM continues to invest in the platform, new hardware improves performance, and modernization tools extend the platform's capability without requiring migration.