Tenant Migration

How to Perform a Microsoft 365 Tenant-to-Tenant Migration for 400 Users

Bushra Parveen Oct 23, 2026 868 views

Question details

The user needs to migrate 400 users, including email, OneDrive, SharePoint, Teams, identities, and multiple domains, from one Microsoft 365 tenant to another.

How to Perform a Microsoft 365 Tenant-to-Tenant Migration for 400 Users

Product: Microsoft 365
Device & OS: not provided
Scenario: Moving a medium-sized organization across two Microsoft 365 tenants, requiring secure transition of administrative settings, licenses, and cloud data.
Observed behavior: The organization must seamlessly transfer all user data and administrative configurations to a new destination tenant without data loss or prolonged downtime.

Before you start

Before initiating the migration, verify that you have purchased and properly assigned all necessary licenses in the destination tenant.

Solution 1Recommended

Use Microsoft Mover or a Specialist Migration Platform

Utilizing dedicated migration tools like Microsoft Mover is the most reliable method for migrating a large user base across tenants.

A tenant-to-tenant Microsoft 365 migration involving 400 users requires robust planning and specialized software. Partner support highly recommends using Microsoft Mover (a cloud file migration tool acquired by Microsoft) or a similar third-party specialist application as an alternative to tools like BitTitan.

Review Official Guidance

Access and review Microsoft's official tenant-to-tenant migration documentation to understand the architecture and limitations for moving email, OneDrive, and Teams data.

Plan Identity and Domain Changes

Map out your identity structures and plan the detachment and reattachment of your multiple domains for the destination tenant.

Configure Connectors

Set up and authorize both the source and destination connectors within your chosen migration platform (e.g., Microsoft Mover) to link the two tenants.

Test the Migration

Execute a pilot migration using a small test batch of users to verify data integrity and permissions before moving all 400 users.

Use Microsoft Mover or a Specialist Migration Platform

Licensing Requirement: Licenses cannot be directly migrated; they generally need to be purchased or assigned separately in the new destination tenant.

Solution 2

Manual Transfer via Open with Explorer

For specific, smaller datasets or isolated SharePoint document libraries, a manual file transfer can serve as a supplementary method.

Free Microsoft Office alternative

Looking for a Cost-Effective Office Suite After Migration?

While planning your Microsoft 365 tenant migration and evaluating licensing costs for your 400 users, consider WPS Office. It provides a highly compatible, free alternative to Microsoft Office, ensuring your teams can seamlessly edit Word, Excel, and PowerPoint documents without expensive overhead.

1. Visit the Website: Go to the official WPS Office website to access the enterprise and individual download options.
2. Download the Installer: Select the appropriate version for your operating system and click the download button.
3. Install the Software: Run the downloaded setup file and follow the on-screen prompts to equip your users with a powerful office suite.

Fully compatible with Microsoft Office formats including .docx, .xlsx, and .pptx.Significantly reduces organizational software licensing costs with robust free features.Lightweight installation that runs smoothly across a wide range of devices.Familiar tabbed user interface minimizes training time for users transitioning from MS Office.

Frequently Asked Questions

Do I need to repurchase Microsoft 365 licenses for the new destination tenant?

Yes, Microsoft 365 licenses generally cannot be transferred directly between tenants. You will need to purchase and assign new licenses in the destination tenant before migrating your 400 users.

What is Microsoft Mover?

Microsoft Mover is a specialized cloud file migration application acquired by Microsoft. It is designed to help administrators efficiently migrate data, such as OneDrive and SharePoint files, between Microsoft 365 tenants or from other cloud storage providers.

Is a manual SharePoint migration feasible for 400 users?

No, relying entirely on a manual transfer using 'Open with Explorer' is highly inefficient and error-prone for 400 users. It is only recommended as a supplementary option for isolated, small-scale file transfers.

Should I test my tenant migration before executing it fully?

Absolutely. It is highly recommended to run a pilot migration with a small group of users. This helps identify potential issues with connectors, domains, or missing permissions before committing to the full organizational move.

Migration & Recovery