I’m researching Microsoft 365 tenant-to-tenant migration specifically from the Teams side. Mailboxes and OneDrive are fairly obvious workloads, but Teams seems more complicated because there can be channels, messages, files, tabs, connected apps, and user memberships involved.

One tool I found, the DRS Softech Office 365 Tenant to Tenant Migration Tool , has a dedicated Teams migration module. According to its documentation, it can migrate public and private Teams channels, channel messages, files, connected apps, and tabs. It also uses one-to-one user mapping to help maintain ownership and membership information.

Another interesting part is Microsoft Planner content linked to a team. The tool says plans, buckets, tasks, and checklists can be included in the same migration pass.

For organizations combining tenants after an acquisition, that could make the project considerably more manageable because Teams isn't isolated from the rest of the Microsoft 365 environment.

Has anyone actually completed a Teams cross-tenant migration? What were the biggest issues you encountered with channels, ownership, files, or Planner content? I’m especially interested in practical experiences rather than just the official migration checklist.