Office 365 Tenant to Tenant Migration – Step By Step Detailed Explanation

Mohit Jha ~ Modified: March 20th, 2023 ~ Office 365 ~ 16 Minutes Reading

The main objective of this step-by-step guide is to help troubled users with the process of Office 365 tenant to tenant migration. It is known that a tenant is a domain account that is attached to the Office 365 Suite. Because of this, the tenant administrator has access to all the features of the chosen subscription.

Due to the maturity of Microsoft 365 in the market, the majority of businesses globally have been using it for a long time. As per the natural business cycle, companies acquire or merge with other companies or divide business units set up on their own.

What are the Major Reasons Behind Office 365 Tenant to Tenant Migration? 

There are several reasons why an organization may need to perform a tenant-to-tenant migration in Office 365. Some of the most common reasons are mentioned below:

  • Mergers & Acquisitions (MA) Activity: While merging two or more companies with each other, or one company acquires another, then, it becomes crucial to combine its Office 365 tenants in order to have a single, and unified environment for better management.
  • Rebranding: Another reason could be the rebranding process, as it requires changing the company’s name or domain. Making it compulsory, to move its data to a new tenant with a different name or domain.
  • Consolidation: In situations, where companies are having multiple Office 365 tenants, managing it could be a cumbersome task. Hence, to simplify management and reduce costs, it requires performing O365 tenant-to-tenant migration.
  • Compliance & Governance: In order to comply with new regulations or meet new governance requirements, organizations might need to migrate their data to another tenant in O365. Hence, it can also be a reason for this operation.
  • Scalability: When businesses grow, they require more resources and scalability in every aspect including Office 365. Hence, in order to upgrade their subscription, they have to migrate their data to an upgraded subscription plan.
  • Cost Savings: It can also be a reason, that an organization may need to move its data to a new tenant just to reduce the costs associated with licensing, support, and other related services.

Furthermore, It is important to note that migrating between tenants has its own challenges and potential risks. It is recommended to plan, test, and execute the migration process with care and with the help of professional migration tools/service providers. Hence, in the coming sections, we have covered all aspects of this operation.

In the coming section, we will talk about the step-by-step working guide for tenant-to-tenant migration, including the preparation, planning, and execution to avoid any errors. We will discuss the Office 365 to Office 365 Migration Tool, a brilliant software for M365 users & Admin.

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5 Steps to Perform Office 365 Tenant to Tenant Migration

  • Step 1. Download, & Launch Software
  • Step 2. Opt Office 365 as Source & Destination
  • Step 3. Choose Mailbox items & apply Date filter
  • Step 4. Log in using Office 365 Admin credentials
  • Step 5. Create Mapping, Validate & Click Start 

Best Practices to Follow Prior to Office 365 (Mircosoft 365) Tenant to Tenant Migration

  • Examine  the Actual Need & Scope of the Migration

In situations where an organization needs to undergo through mergers and acquisitions process, communications become quite limited. And eventually, all the intense pressure goes to the IT department in order to perform this data transfer as soon as possible.

“Hurrying will cause problems” remember this famous quote while executing the migration process. It is quite important to take time in order to plan and execute the whole process in a more systematic way.  Moreover, make sure to make a list of items to migrate such as emails, contacts, calendars, documents, or everything together depending on the firm’s respective needs.

  • Back-Up the Current Source & Destination Environments

Backing up your current source and destination environment is vital before proceeding toward Office 365 tenant to tenant migration. It always works as an insurance policy – As data migration is a technical & complex process to hands-on.

Therefore, just in case anything goes wrong with the migration operation, then it can save your organization’s crucial data. It will ensure a smooth flow of business activity & communication with minimum disruption.

  • Create a Comprehensive Inventory Analysis of Your Source Environment

This is another best practice to create a complete inventory of the source and the destination target environment. Before putting them for migrating from one M365 tenant to another.

You should be aware of what to migrate and what to leave behind with all the user accounts data sizes they are having, including email and OneDrive. Once you complete this step, then there is nothing more important left behind.

  • Now It’s Time to Plan the Migration

Once you determine the number of data and user accounts that need to be migrated, then it’s time to plan the migration process. As the organization should also be aware of the downtime involved in this process.

And mostly they cannot afford the downtime that it may take. As it can hamper the running of business activities. Therefore, phase migration would be the best option to do hands-on as you can determine the user work productivity throughout the whole migration process.

Regardless of whether the user’s data is being migrated or not. They would simply be able to communicate and continue using their Office 365 email account, keeping the whole migration process invisible (in the background) to users of the organization.

  • Keep Effective Communicate Before, During & After Migration

It is the most important best practice to have effective communication throughout this migration in Microsoft 365 tenants process to encounter any error that may take place. Employees must be informed of the different working scenarios that might occur. IT managers need to manage all the licensing requirements that may happen.

  • Make Sure to Monitor & Report on the Real-Time Migration Process

In the list of best practices for Office 365 tenant to tenant migration, this is the 2nd last point to remember and follow. You should ensure an appropriate way to monitor the status of the whole migration process in real-time, coordinate with other users and activities, and early detect any type of error encountered.

You can check the complete pre & post-migration checklist plan for Microsoft Office 365 here.

Now, Let’s Discuss the Most Important Pre-Migration Stage Step By Step

Step 1. Domain Preparations

It is crucial to ensure the availability of enough licenses for the target Microsoft 365 tenant. Then, for a smooth and error-free migration, you should also create the respective admin accounts in the source and the destination.

Another very important step to do is, to create the respective user mailboxes, rooms /resources mailboxes, and distribution groups in the destination. You can use the AD DS tools for manual configuration or you can use directory synchronization as well.

Lastly, don’t forget to train your end-users regarding the post-migration changes that they might face in Microsoft 365.

Step 2. Online Domain verification

The next very crucial step is to verify the respective tenant domain in the M365. In order to do the same, you need to add the source domain in the destination M365 admin center and then you can create TXT records in DNS settings.

There are other ways as well, you can use the domain connect to verify the respective domain or you can the name servers in the Domain DNS settings in the respective registrar. It can take time to reflect the changes, deepening upon the method you have selected, it can vary from 30 min to up to 72 hours for the changes to reflect.

Step 3. Scheduling Your Tenant Migration

Start with creating a CSV file, that contains the list of respective user mailboxes that are to be transferred. It will later be used for group mapping or bulk migration. Then, disabling the directory sync is also an important step to avoid any modifications in the source tenant account AD DS to Office 365 platform.

Step 4. Prepare the Source Tenant

We need to remove the primary mail domain from the source tenant before initiating the migration process. In order to accomplish this task, we need to reset the default email address to the initial email address of Microsoft Office 365.

Then using the Lync Admin Portal, we need to remove all the respective Lync licenses from the source tenant. Moreover, secondary email addresses must be removed from all the tenant objects.

We can use the Windows PowerShell command i.e. Get-MsolUser -DomainName It will retrieve all the objects still using the source email or denying the removal.

Step 5. Prepare the Destination Tenant

Follow the below-guided instructions to prepare the destination tenant accordingly:

  • In the very first step, we need to configure the auto-discover CNAME.
  • Create the new user accounts respectively in the destination domain and assign required licenses receptively.
  • We need to change the mail routing & point the MX record to the new Office 365 email address if the user mailbox is still active.
  • Lastly, we need to test the email flow for receiving and sending from the target tenant.

Invest in the Reliable & Error-Free Professional Utility for M365 Tenant to Tenant Migration

For those who are new to the migration arena, let’s make it clear that there is no manual workaround available. Upon research, experts have found no direct method smart enough to migrate the entire data successfully.

So, to make it a painless procedure, we are introducing the expert’s choice i.e. SysTools Office 365 to Office 365 Migration Tool.

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Why go for a tool? Well, that is because Microsoft itself suggests that you should use trusted software for migration.

Since it is not only about a successful process to migrate Office 365 tenant to another tenant, the need to keep the data safe is also a concern. If the software you use is migrating the data without any pause but the data is lost during the process, what is the point of using the solution?

The software mentioned here is the perfect approach to avoid any data loss and have a quick, safe, & successful migration.


Highlighted Features of the Utility for Office 365 Tenant Migration

  • Allows migration of all the items like Emails, Calendars, Contacts, Documents, etc.
  • Perform Office 365 tenant-to-tenant migration for entire or selective mailboxes
  • Offers a Date-range filter to migrate selective data from a certain time period
  • Use the Delta Migration feature for exporting newly arrived data after the first process
  • Option to set account-based priorities for migrating certain accounts before others
  • Facility to import CSV files to add Source and Destination mailbox users
  • Shared mailbox migration is also supported by the software
  • Works on Windows 10 (64-bit) and Windows Server versions 2012 & 2016

Before learning the steps, find the prerequisites as described.

Pre-Requisites for Migration Between Office 365 Tenants Via Tool

There are certain pre-requirements of the tool that you should know and fulfill before moving to the steps. These requirements are:

  1. Before migration, ensure that the destination user(s) is already created at the destination admin account.
  2. You should have application registration in MS Azure Active Directory and the API permissions for source & destination must be enabled.
  3. The activation code is needed for the tool to perform the process.
  4. The admin account should have the assigned license of Microsoft 365.

Software Steps to Perform Office 365 Tenant to Tenant Migration

Step 1. Launch the software and in the Setup tab, select Office 365 for both the Source and Destination accounts.


Step 2. Here, choose the categories that you want to export and set the Date-filters for each in the Workload Selection field.

Step 3. Enter the credentials for your Office 365 account in the Source Window. Press the Validate button and Next.

Step 4. Fill in the details for the Destination Office 365 account and Validate it. Hit Next for moving further.

Step 5. Choose the Fetch Users or Import Users option to add mailbox users and perform Microsoft Office 365 tenant to tenant migration.

Step 6. Complete the process by setting priorities for accounts, mapping the source and destination user accounts, and hitting Start Migration.

In case there are certain files that you may have received during or after the process, you have the option to export only those items.

Mark the Delta Migration option which will re-scan the mailbox again for any newly arrived data. If there is any new file, the tool will export only those files.

What are the Needs to Perform Migration Between Office 365 Tenants? 

Meaning, if one company (using M365) acquires another company (also using M365), they might need to migrate the users, data, & domains of the acquired company.

This may seem like an easy enough task just like flicking a switch, however, that is not the case. There are a lot of things that an admin needs to take care of during the migration task.

The more services you use in Office 365, the bigger the migration project for all the data stored in these services and the more complexity.

Recommendation – You can visit here to Move a Domain Between Office 365 Tenants

Performing Office 365 Tenant to Tenant migration is now a global concern for users and enterprises. The greatest challenge among them is to determine the data that users can move and cannot move to the destination tenant.

There are various Office 365 migration services available today that offer access to several types of data stored on Office 365. However, a few shortcomings & limitations are there in order to access them all. Let’s discuss the main issues and challenges while performing this data migration.

Users should be Aware of the M365 Tenant to Tenant Migration Issues & Challenges

  1. The very first concern for business organizations having multiple Office 365 domains, is that require their coexistence at a stretch. Then, it becomes a tough & tedious process to perform a migration between tenants.
  2. Businesses have tons of data for users, emails & other mailbox categories, in this scenario data migration, can not be accomplished instantly. Hence, to ensure a smooth data transfer by migration teams, organization employees need to inform & collaborate with others by scheduling a meeting.
  3. One of the biggest challenges while performing Office 365 tenant to tenant migration in Office 365 is to ensure data integrity. They get stuck when they do not insure the source email data is properly before migration.
  4. It can create data loss & data corruption when migrating data from older versions of MS Exchange such as 2003 and 2007. As it has a limit on mailbox size of 2GB when it exceeds the limit, it could lead to data loss.

The above-listed points are only some of the few issues & challenges that can occur while performing this operation. One can face various issues and complications while performing the above operation without any preparation and planning. 

In Brief

The Office 365 tenant to tenant migration procedure is a difficult operation that needs to be handled with care. If you perform this task using any tool which is not certified, you may end up losing your data.

To keep the data safe and have an effortless yet successful exportation procedure, the above tool is the best shot. Even migration experts and professionals prefer using this utility.

Frequently Asked Questions

Q. How do I easily perform Tenant to Tenant migration in Microsoft Office 365?

This step-by-step guide will help you perform a migration between Office 365 tenants, using the automated solution (suggested in this blog). There is no direct or simple manual solution available for this task.

Q. Can I migrate the user’s mailbox (emails, contacts, calendars, tasks), admin mailbox, and shared mailboxes from source Office 365 Tenant to destination Tenant?

Yes, with the help of a given solution you can easily migrate mailboxes between M365 Tenants.

Q. I have to perform the entire user’s mailbox migration between Office 365 Tenants, this blog will help me?
Yes, here we have provided a method to simplify Office 365 tenant to tenant migration, it will move all user mailboxes at a time.
Q. What is a Microsoft Office 365 tenant?

When you create a Microsoft 365 tenant, it becomes a center of services allocated to your organization. In addition to this, it gets registered with two different DNS entries by default for example –  if the tenant name is abc, then DNS entries will be : 


A tenant serves as an isolated container for different subscription plans and the licenses assigned within them for respective user accounts. When you set up the tenant, you can assign it to a particular geographical location. One can have multiple geographical locations set up in a single tenant and can also move them based on their needs. In order to keep your tenant ready for users, groups, licenses, and cloud apps, it becomes crucial to prepare and perform your tenant configuration carefully.

Q. What is o365 tenant-to-tenant migration?

A tenant-to-tenant (T2T) M365 migration transfers data and resources such as users, mailboxes, Teams, SharePoint, OneDrive data, etc to the destination M365 tenant. Business Mergers, Divestitures, and Acquisitions are some of the main reasons for M365 tenant migration.

Q. Why do tenants migrate to tenants in M365?

In an organization managing, multiple tenants of the Microsoft 365 suite becomes a monotonous and cumbersome task for IT admins. It utilizes the maximum IT resources and staff for ensuring different permissions, and licenses, and performing other day-to-day activities. In order to get rid of this, various businesses tend to migrate their tenants to another or single tenant.  

Q. Can we merge Office 365 tenants using this tool?

Yes, using the above-mentioned software solution, you can easily merge or migrate different or multiple Office 365 tenants’ data into a single tenant. Moreover, you can simply migrate the source tenant data to the destination M365 tenant and once, the data transfer gets completed then you can delete the source M365 tenant. 

Q. Where is my Microsoft tenant located?

You can find and view your tenant information by following the below steps:

  • Step 1. Log in to your Office 365 account and go to the Microsoft 365 Admin Center. Navigate to Settings
  • Step 2. Now, click on Org Settings and then click on the Organization Profile tab. 
  • Step 3. Then click on  Data location, here you can see all the data related to your tenant such as the location of data, etc.
Q. How much time does it take to perform M365 tenant migration?

Migration time depends upon various things such as – data size that needs to be migrated, host machine configurations, internet bandwidth, etc. Hence, answering such a query certainly is not possible. On average, it could take up to two weeks to migrate a batch of not more than 1000 mailboxes.

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