I'm planning a tenant consolidation project and would appreciate advice from anyone who has already done this successfully. The goal isn't just mailbox migration—we also need to migrate SharePoint sites and OneDrive accounts while preserving permissions, metadata, and document libraries.

Several colleagues recommended looking at MacSonik Office 365 Tenant to Tenant Migration during my research because they had positive experiences with automated tenant migrations. After reading more about similar migration utilities, I noticed that Graph API-based solutions seem much more reliable than relying entirely on PowerShell scripts.

The features that stood out to me were automated user and mailbox mapping, bulk migration support, and the ability to maintain SharePoint structure without breaking permissions. Another useful option was the Date Range Filter, which lets administrators migrate only selected folders or data within a specific time period instead of everything at once.

Since our organization has over a thousand users, minimizing downtime is a huge priority. We're trying to avoid interruptions while ensuring business continuity throughout the migration process.

Has anyone here migrated a large Microsoft 365 environment recently? Did automated tools really save as much administrative effort as vendors claim, or did you still have to perform significant manual corrections afterward? I'm interested in hearing real-world experiences before recommending a solution to management.

https://www.macsonik.com/office-365-tenant-to-tenant-migration/