I’m planning a cloud migration where an organization currently uses Google Workspace for email, Drive, and other collaboration data, while the destination environment is Microsoft 365. The main concern is making sure the migration does not turn into a simple mailbox-only transfer because there is important data outside Gmail as well.

The Workspace accounts contain emails, contacts, calendars, tasks, and attachments, while Google Drive includes My Drive and Shared Drives. There are also Google Chats and Spaces that may need to be retained. I’m therefore looking for a method that can handle different types of Workspace data while keeping the existing folder and label structure intact.

For the email side, I’ve been researching ways to migrate Google Workspace to Office 365 without first exporting everything to local files and then manually importing it again. A direct migration sounds more practical when multiple users are involved, particularly if administrators can map source accounts to their Microsoft 365 destinations.

Another thing I’m concerned about is account mapping. In a business migration, the source and destination usernames may not always match. The product information I reviewed mentions 1-to-1, 1-to-many, many-to-1, and many-to-many mapping, along with CSV-based batch mapping and Workspace Admin Domain Wide Delegation. That seems useful for larger organizations where configuring every mailbox individually would take considerable time.

I also came across the SysInfo Google Workspace Backup Tool while comparing different approaches. Its documentation says that Gmail, Drive, and Chat data can be migrated directly to Microsoft 365, while Google documents can be converted into Office formats when moving Drive content.

The ability to use date filters and duplicate handling is also interesting because I may not need to move every item from every account. There are also reports showing completed, skipped, and failed items, which could help during verification.

Has anyone here handled a Google Workspace to Microsoft 365 migration involving both mailboxes and Drive data? I’d especially like to know how you approached account mapping and verified the migrated data before decommissioning the old Workspace accounts.

For anyone who has had to migrate from Google Workspace to Office 365, did you move everything in one operation, or did you first run a smaller pilot migration to check the mapping and folder structure?