Merge or split Microsoft 365 tenants without breaking mail flow
CloudServus plans and executes cross-tenant migrations for Exchange, OneDrive, SharePoint, and Teams, built on Microsoft's own migration tooling and identity mapping requirements.
Talk to an Expert →What moves in a tenant-to-tenant migration
Microsoft's migration orchestrator moves content, not identities. Exchange mailboxes, OneDrive files, and Teams chats and meetings migrate as one coordinated batch, but only after every user is precreated and licensed on the target tenant and an identity mapping file connects source accounts to target accounts. Skip that step and the migration won't start.
SharePoint sites move through a separate tool, licensed per 100 GB of data and currently available to Enterprise Agreement customers. It's a one-time move: no incremental or delta passes once a site lands on the target tenant. Teams channels and their structure don't migrate at all, on either tool. Anyone who needs old channels working after the move has to rebuild them on the target tenant, and that rebuild is its own planning task, not a footnote.
How we run your migration
Discovery and identity mapping
- Environment assessment across Exchange, OneDrive, SharePoint, and Teams to scope what migrates and what gets rebuilt
- Identity mapping completed between source and target tenant before any content migration starts
Configuration and trust
- Tenant trust established between source and target so SharePoint content moves without ever leaving Microsoft's cloud
- Licensing plan for the per-user mailbox/OneDrive licenses and per-100GB SharePoint licenses Microsoft requires
Staged content migration
- Exchange mailboxes, OneDrive, and Teams chats migrated together to respect Microsoft's dependency order between workloads
- SharePoint sites migrated separately, each capped at 5 TB and 1 million items per site, since there's no second pass
Cutover and rebuild
- Cutover weekend or phased batches, scoped to how many users and how much risk your organization can absorb at once
- Teams channels and connected apps rebuilt on the target tenant, since Microsoft's tooling doesn't carry that structure over
Built around how mergers happen
Microsoft supports three migration models: a single cutover event, a phased migration run in batches, or a tenant split for divestitures. We match the model to your deal size and timeline instead of forcing every migration through the same playbook.
A single-entity acquisition with a few hundred mailboxes usually runs as one cutover weekend. A multi-brand consolidation with tens of thousands of users needs a phased plan, batch by batch, so the business keeps running while the migration catches up.
What changes once everyone's on one tenant
Collaboration stops requiring guest links and external sharing workarounds once every team sits in the same directory. Security policies, conditional access, and data governance apply the same way across the combined organization instead of two separate rule sets.
Licensing gets simpler too. Duplicate Microsoft 365 subscriptions from the pre-merger organizations get consolidated, and redundant seats get cut instead of renewed at the next contract cycle.
Ready to combine your Microsoft 365 tenants?
Talk to a CloudServus architect about your merger, acquisition, or divestiture timeline. We'll scope the migration and tell you straight what it takes before you commit to a cutover date.
Talk to an Expert →