SharePoint: Advanced Management - Inactive files policy
SharePoint administrators can now automatically archive files that haven't been accessed for 6-48 months to cold storage, reducing active storage costs while maintaining file accessibility, metadata, and compliance attributes. This requires enabling Microsoft 365 Archive and billing configuration first.
Microsoft's description
SharePoint administrators can use the Inactive files policy in SharePoint Advanced Management to automatically archive files based on when they were last accessed. The public preview is available through PowerShell only. Admins can set an inactivity threshold from 6 to 48 months, scope policies to all SharePoint sites or selected sites, include or exclude file types and sites, and use What-If mode to review impact before activation. Eligible files move to the Microsoft 365 Archive cold-storage tier while remaining in place and retaining their metadata, permissions, compliance, and searchability. Microsoft 365 Archive and pay-as-you-go billing must be enabled.