Microsoft 365
Microsoft 365 Tenant-to-Tenant Migration
A tenant-to-tenant migration moves users, mailboxes, OneDrive, SharePoint, Teams and identity from one Microsoft 365 tenant into another. Businesses need it after an acquisition or merger, a divestiture, a rebrand with a new domain, or when leaving a reseller-controlled tenant. CloudTechForce delivers it in three to eight weeks with a coexistence plan so both companies keep working, and a fixed price per user.
Last reviewed 2026-09-05 by Ammad Qammar, M365 Technical Lead.
When you need this
| Situation | What has to happen |
|---|---|
| Acquisition or merger | Bring the acquired company's users, mail, files and Teams into the acquirer's tenant; keep both email domains working during the transition |
| Divestiture or spin-off | Carve a business unit out into its own new tenant without exposing the parent's data |
| Rebrand or new primary domain | Move to a new domain and, often, a clean tenant with new naming standards |
| Leaving a GoDaddy or reseller tenant | Defederate and move into a tenant you own and administer |
| Consolidating multiple tenants | Several small tenants from years of growth merged into one with a single identity and security baseline |
What moves and what does not
| Workload | Migrated? | Notes |
|---|---|---|
| Mailboxes, archives, shared mailboxes | Yes | With folder structure, categories and rules where possible |
| Calendars and delegations | Yes | Delegation and room permissions rebuilt post-move |
| OneDrive | Yes | Sharing links re-issued; internal shares mapped |
| SharePoint sites and libraries | Yes | Site by site with permission mapping; workflows rebuilt |
| Teams (channels, files, tabs) | Yes | Channel conversations migrated as history where the tool supports it; private channels handled individually |
| Entra ID users and groups | Yes | Recreated or synced; passwords reset with a managed rollout |
| Intune device enrolment | Re-enrol | Devices must leave one tenant and join the other; we script and schedule it |
| Licences | Re-purchased | Timed so the old tenant is not paid for longer than necessary |
| Custom domains | Yes | Removed from the source and verified on the target during cutover |
| Power Platform, Planner, Bookings, Forms | Partial | Exported and rebuilt; scoped in discovery |
Microsoft documents the native option in cross-tenant mailbox migration; third-party tools cover SharePoint and Teams.
How we run it
- Discovery (week 1). Inventory of both tenants, licence and domain plan, naming standards, conflict report (duplicate users, groups, site names), security baseline for the target tenant.
- Coexistence design. Mail routing between tenants, calendar free/busy sharing, address list sync so people can find each other during the transition.
- Pre-staging (weeks 2–5). Mail, OneDrive, SharePoint and Teams copied in waves while both tenants remain live.
- Cutover (weekend). Domain moved, MX switched, delta sync, passwords issued, devices re-enrolled through Intune and Autopilot, Outlook profiles rebuilt automatically.
- Stabilisation (2 weeks). Priority help desk, permission audit, decommissioning plan for the source tenant.
What it costs
| Component | Price |
|---|---|
| Per user (mailbox and OneDrive) | Quoted in writing |
| SharePoint sites | Quoted in writing |
| Teams | Quoted in writing |
| Coexistence setup | Quoted in writing |
| Device re-enrolment | Quoted in writing |
| Project minimum | Quoted in writing |
Merger timelines often make this an urgent purchase; we can begin discovery within five business days.
Risks we manage for you
- Users locked out on Monday morning because passwords were not distributed safely.
- Devices stuck in the old tenant's Intune because re-enrolment was not planned.
- Shared mailboxes and calendars that worked in the old tenant and were never inventoried.
- Domain removal blocked by leftover objects in the source tenant, delaying cutover by days.
- Compliance holds and retention policies silently blocking mailbox moves.
FAQ
Frequently asked questions
How long does a tenant-to-tenant migration take?
Three to eight weeks depending on user count, SharePoint size and whether coexistence is needed. Small rebrands can be done in three weeks; mergers with hundreds of users and complex SharePoint take six to eight.
Can both companies keep working during the migration?
Yes. Coexistence keeps mail flowing between the two tenants and shares calendar availability until the final cutover.
Will Teams chat history move?
Channel messages can be migrated as read-only history with most tools; private chats are exported for reference. We confirm the exact behaviour of the chosen tool in discovery.
What happens to the old tenant?
It is kept read-only for an agreed period (usually 30 days), then licences are removed and the tenant is decommissioned or retained for legal hold as required.
What does it cost?
A written fixed price is issued after a one-week discovery.
Talk to an engineer, not a salesperson
Book a 15-minute call, or send us your current IT invoice and we will tell you what we would change. No obligation.
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