If you're dealing with a merger, acquisition, or company rebranding, moving OneDrive data between Microsoft 365 tenants can feel intimidating at first, but it doesn't have to be complicated if you approach it the right way. The "easiest" method really depends on your scale — for a handful of users, Microsoft's native cross-tenant migration option in the SharePoint Admin Center can get the job done, though it's fairly manual and limited in terms of reporting and validation.

For anything beyond a small team, the simplest and most reliable path is using a purpose-built migration tool rather than trying to script something together or rely purely on native options. What makes it "easy" in practice comes down to a few things: automated permission and metadata mapping so you're not manually recreating access rights, incremental or delta migrations so users aren't locked out for extended periods, and clear pre-migration reporting so you know exactly what's being moved before you commit.

We used the DRS Softech Tenant to Tenant Migration tool for a recent OneDrive migration, and it simplified a lot of the manual work — permissions, versions, and folder structures carried over without extra scripting, and the delta sync meant end users barely noticed the transition until the final cutover.

Bottom line: if you're moving a small number of accounts, native tools might suffice. But for anything larger or more complex, a dedicated migration tool will save time and reduce the risk of data or permission loss.