Tenant-to-Tenant Migration Has Changed. Has Your Tooling Kept Up?
Five years ago, when someone said “Exchange migration,” they usually meant moving on-premises Exchange to Microsoft 365. That’s still happening, but it’s no longer the dominant scenario. Today, the migration I see most often is Microsoft 365 to Microsoft 365 — tenant to tenant — driven by mergers, acquisitions, consolidations, and divestitures.
That shift matters because tenant-to-tenant is exactly where most tooling falls down. The PowerShell-and-spreadsheet approach that worked for a one-time on-prem cutover doesn’t scale to a deal timeline. You need something built for the modern shape of this work: something menu-driven, easy to use, and fast.
I recently walked through Stellar Migrator for Exchange with the Stellar product team, and three things stood out:
Delta migration is on by default. Re-run any job and it only moves new and changed items. No duplication, no overwrite. That sounds obvious, but plenty of tools still get it wrong. Stellar does the right thing automatically.
The wizard keeps the path short. Eight steps, none wasted. Auto-mapping handles matched usernames; manual mapping and CSV import cover the rest. No PowerShell required to connect to Microsoft 365 — the tool handles Azure AD app registration on your behalf, with a documented manual path if you’d rather do it yourself.
Licensing is predictable. One license per source mailbox, with a 30-day window of unlimited re-runs from when you start the migration job. Plan the count upfront and there are no surprises.
I’m not the only MVP who’s landed here: Joseph Afeso, Shabaz Dar, and Szymon Bochniak have each evaluated this tool in their own labs and reached similar conclusions — different angles, same takeaway: it works, and it doesn’t make you fight the software while you’re fighting the migration.
If you’re planning an Exchange-to-365 project, a tenant consolidation, or an Exchange upgrade, watch the video above for the full walkthrough, then grab the free trial. Two mailboxes are enough to know whether this is the right tool for what you’re trying to do.
