Tenant-to-Tenant Migration Timeline Estimator

Estimate the planning complexity of a Microsoft 365 tenant-to-tenant migration.

How many users are moving?

Include active users, shared mailboxes, guests, and external collaboration needs.

• Under 100 users
• 100-1,000 users
• 1,000+ users

How many workloads are in scope?

Mail, OneDrive, SharePoint, Teams, groups, devices, apps, and Power Platform each add sequencing requirements.

• Mail only or limited scope
• Mail plus files/sites
• Full tenant move

How complex is identity?

Consider domains, Entra ID, synchronization, Conditional Access, MFA, devices, and administrative roles.

• Simple cloud identity
• Hybrid or multiple domains
• Complex identity and security dependencies

How much data is involved?

Storage volume affects tool selection, wave sizing, throttling, and validation.

• Low volume
• Moderate volume
• High volume or sensitive data

Is coexistence required?

M&A and divestiture projects often require mail routing, address book, collaboration, and staged cutover decisions.

• Single cutover acceptable
• Short coexistence window
• Long or complex coexistence

How fixed is the deadline?

Legal, brand, acquisition, or contract dates can reduce flexibility.

• Flexible
• Target date within 3-6 months
• Fixed or urgent cutover date