Microsoft 365 Tenant-to-Tenant Migration · Modern Work (Microsoft 365)
We have to bring two Microsoft 365 tenants together without stopping the business.
For CIO, COO, IT director, Microsoft 365 lead, merger or transformation sponsor
A merger, divestiture or rebrand usually means moving people's mail, files, sites and teams from one Microsoft 365 tenant to another on a business timeline. The risk sits in the details: hybrid Exchange, archives, guest access, private channels and file shares. We start with a fixed-scope assessment that tells you what the migration will really take before you commit to a date. Then we migrate in waves after a pilot, keep both organizations working together through coexistence, and support people through cutover and hypercare.
How we work
What we do
Open a step to see what happens and what you receive.
Advisory: Tenant Consolidation & Migration Strategy
Advisory, with an optional ongoing vCIO cadence. For sponsors of a merger, divestiture, rebrand or consolidation who need a defensible approach before funding a migration.
- Business-driver and constraint workshop
- Document-based review of tenant, identity, licensing and workloads
- Target tenant, domain and identity options, with the trade-offs
- Coexistence and cutover approach matched to your tolerance for disruption
- Licensing rationalization principles, and risk, compliance and change-impact analysis
You receive: a target-state architecture options paper, a migration approach and coexistence recommendation, a risk and dependency register, a phased roadmap and an executive briefing.
Assess: Tenant-to-Tenant Migration Readiness Assessment
Fixed fee. For IT leaders who need facts on mailboxes, sites, teams, file shares and coexistence before approving a migration.
- Read-only discovery of mail, archives, sites, teams, guests and file shares
- Identity, domain and licensing review, including address-list sync readiness
- Endpoint and device-management impact review
- Complexity scoring, coexistence and cutover options, and a tooling recommendation
You receive: a readiness report and complexity scorecard, coexistence and cutover options, a draft wave plan and an effort range for the migration.
Implement: Tenant-to-Tenant Migration
Project under a statement of work. For organizations with an approved move and a target date.
- Detailed design, runbooks, wave plan and rollback criteria
- Target tenant preparation and security baseline
- Coexistence: shared address book, mail flow and cross-tenant Teams collaboration
- A pilot group with a go/no-go decision, then migration in waves
- Communications, end-user training and floor-walking for each wave
- Final cutover with delta syncs, hypercare and source-tenant decommission handover
You receive: a configured target tenant, migrated mail, OneDrive, SharePoint and Teams, cutover completion and hypercare reports, and as-built documentation for source-tenant decommission.
Want to know what this would look like for you?About 30 minutes with a practitioner from the practice that does the work. You’ll leave with a clear view of your next step.
Book a 30-minute conversationOutcomes
What you can expect
- A verified inventory before you commit to a dateAssessment
- A cutover approach matched to your businessAdvisory
- Content moved with permissions and structure intactImplementation
- People supported through cutover and hypercareImplementation
Each outcome is labelled with the stage that delivers it. An assessment or advisory engagement on its own does not include the implementation work.
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Select the needs that apply. We’ll collect them here so you can review the fit.
DeliverablesDeliverables by phase (18)
Advisory
- Target-state architecture options paper
- Migration approach and coexistence recommendation
- Risk, dependency and compliance register
- Phased roadmap and executive briefing
Assess
- Discovery data pack
- Readiness report and complexity scorecard
- Coexistence and cutover options analysis
- Tooling recommendation
- Draft wave plan
- Effort range for the migration
Implement
- Detailed design document
- Migration runbooks and wave plan
- Change and communications plan
- Configured target tenant and coexistence
- Pilot results and go/no-go report
- Migrated mail, OneDrive, SharePoint and Teams
- Cutover completion and hypercare reports
- As-built documentation and source-tenant decommission handover
Good to know
Questions leaders ask
Will people lose email during the migration?
The approach is designed to keep people working: coexistence with a shared address book and cross-tenant Teams collaboration, a pilot first, final delta syncs at cutover, and hypercare afterwards. We don't promise zero disruption; we plan and test to keep it small.
Can't we just do it in one weekend?
Sometimes, yes. Whether a single weekend works depends on volumes, hybrid Exchange, archives and how much change people can absorb. The assessment compares weekend and phased approaches against your environment.
We'll buy a migration tool and do it ourselves. Why an assessment?
The tools are good, and we use them. Most of the risk is in the decisions around them: coexistence, wave grouping, mail flow at cutover, and what happens to devices and OneDrive sync. The assessment gives your team that plan, whether or not you ask us to run the migration.
Which migration tools do you use?
The assessment recommends a tool based on your environment. You provide the tooling licenses.
Do you handle end-user training and communications?
Yes, for the migration itself: a change and communications plan, end-user training, communications and floor-walking for each wave.
Do you migrate Power Automate flows and custom SharePoint solutions?
The assessment identifies them. Deep re-engineering of flows or custom solutions is outside the reference scope and is handled through change control.
What about devices?
The assessment reviews endpoint impact. Device re-enrollment and Intune design are not part of the migration scope.
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Talk to us about Microsoft 365 Tenant-to-Tenant Migration
Tell us the decision, deadline or problem in front of you.
- A reply from the practice that does the workThe practitioners who would deliver it.
- A short conversationWhat needs to happen, and by when.
- A written proposalWhat you would receive, how long it takes and the fee, before you commit.
No cost, no obligation.
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About 30 minutes with a practitioner from the practice that does the work, not a salesperson. It’s about your situation, and you’ll leave with a clear view of your next step. No cost, no obligation.
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