A Standard Guide for Tenant to Tenant Office 365 Migration in 2021 for 100+ Users

How to do Tenant to Tenant Office 365 migration is a question of million bucks. In this, the organization migrates workload from xyz.onmicrosoft.com to abc.onmicrosoft.com domain. Most of the time, what IT users do is take the backup of one Office 365 tenant and restore it into another. However, this is not the expert way for Tenant to Tenant migration in Microsoft 365.

Users also export Office 365 user mailboxes as PST files from the source tenant and then import PST files into the target tenant. The better alternative from all these, make use of a powerful and recognized third-party application. It will help you do all the operations like migrating data between tenants, creating users on the target Office 365 tenants, and more automatically.

Before moving ahead with the documentation revealing the preparation, step-by-step process, common challenges, and robust solution for Office 365 tenant to tenant migration, know that Microsoft doesn’t have an in-house mechanism for the tenant to tenant migration in O365.

Enterprises running on the Microsoft 365 license service can access all the traditional Office apps in one place. They can manage and share the workload with several applications like One Drive, OneNote, Power Automate, Calendar, People, Skype, PowerPoint, and many more. It can be the primary reason why the adoption of Office 365 is increasing in the enterprise world. However, managing several Office 365 accounts is not an easy task. Due to merger, re-branding, and acquisition needs, organizations plan for Office 365 tenant to tenant migration.  

This migration can be for the same domain or a different domain, depending on the organization’s needs. The scenario in which the source and target both are Microsoft 365 is called Office 365 tenant to tenant migration for the same domain.

Enterprises undergoing MS Office tenant to tenant migration switches:

• Data and user account from old Office 365 tenant to an empty/ new tenant.
• Emails and mailboxes between Office 365 tenants.
• Workloads including Exchange Online, SharePoint, One Drive, Teams, etc.

Major Tenant to Tenant Microsoft Office 365 migration issues are following:

The below-highlighted scenarios are the results of a survey conducted by the RecoveryTools team. It reveals some of the common challenges enterprises face during the Office 365 to Office 365 tenant migration.

I’m going to migrate a customer to their O365 tenant. I’ve started with a Mailbox, but after the migration (completed), I’ve seen that many emails have not been migrated to the tenant (thousand emails!). Then, I’ve migrated the same mailbox into a PST without losing emails. What’s the cause? – Kevin Williamson

I have reviewed some of the O365-to-O365 mailbox migration tools. However, the source tenant is not providing Admin access, is there any way around this? – Peter

Can migrate from Office 365 to Office 365 tenant migration without any loss of data? – Subbu

I am the administrator of a small nonprofit trying to migrate two users from the Office365 online environment to another (tenant to tenant) migration. I would like to know the best solution for the small data transfer I am trying to manage. – Mary

Shall I migrate the Office 365 US tenant to Office 365 India tenant using any tool? -Edward

In the above scenario mentioned, every user has a unique concern for Office 365 migration between tenants for the same domain. First, whether you are an IT Expert or a standard user, you need to know to prepare the environment for the mechanism. The below section detail everything about it

The Checklist for Tenant to Tenant Migration in Office 365 Includes:

The below-mentioned preparation checklist should be accomplished a couple of weeks from the intended migration date.

Prerequisite for the Migration

1. Ready your Source and target tenant.
2. List object in the new tenant for migration.
3. Inform, and prepare domain user account whose data will be migrated.
4. Create a CSV file of Office 365 source tenant user accounts.
5. Determine the Time To Live before migration to avoid disruption in mail flow.
6. Plan Syncing of Azure Active Directory data precisely before tenant migration.

On the day of Microsoft O365 Tenant to Tenant Migration Mechanism:

After preparing for the above scenarios for the Microsoft 365 Tenant to Tenant migration, the company needs to pay attention to a few things like:

1. Stop the activity of the incoming mails as they can’t be synced to the target tenant.
2. Configure and verify the source tenant into the target tenant.

Post Tenant to Tenant migration process:

After you have successfully migrated data from one tenant to another Office 365 domain; please take action on the following:

1. Assign primary addresses to the user and inform users to set new passwords.
2. Check that all the data, including email, contacts, calendars, and more, are switched to a new domain.
3. Clear Outlook auto-complete list to stop the delay of new emails and other data.

A Step-by-Step Guide for Office 365 Tenant to Tenant Migration for 50+ Users

Below are the steps for enterprise or project managers to migrate 100 Office 365 users from tenant to tenant.

1. Choose the source and target tenant and create an Admin account.
2. Select User Mailbox, resources, and distribution groups as the target.

Read a note: In case of manual synchronization of source domain to target, the user can use AD DS tools.

1. Verify the target domain in Office 365 and add a source in the admin center.
2. Now, create text records in Domain Name System, and changes will be seen inn72 hours.
3. Create a CSV file consisting of the list of user mailboxes.
4. From the source domain, check the lowest TTL value on the MX record.
5. Switch off the directory sync for the source Office 365 tenant.
6. Discard all the Lync licenses from the source tenant.
7. Reset from initial domain- email address of distribution lists, rooms, & resources.
8. Clear the secondary email address from all tenant objects.
9. Now, run the command “MsolUser -DomainName xyz.com to migrate all the objects using the primary email address.
10. After the new domain configuration in the tenant, activate the user account and assign licenses.

A Special Note 

The method mentioned above is applicable for small amount user migration from Office 365 Tenant to Tenant. For an organization preparing to migrate more than 300+ user mailboxes from Office 365 tenant to tenant, a robust third-party solution will be an ideal choice.

Download RecoveryTools Office 365 Migrator toolkit to manually migrate Office 365 mailbox to Office 365 or use the Admin option.

Time to Make a Move!

We have mentioned all most everything you should know about migration. Now, you need to decide on:

• What you all need to migrate as Microsoft 365 tenant to tenant migration?
• How many Office 365 user mailbox you need to migrate between Office 365 tenants?
• What’s the right time you can plan the migration on your premises?
• Which is the method you need to choose for Tenant to Tenant Office 365 migration?