Below you will find some of the common reasons why an organisation may need to perform a Microsoft Tenant to Tenant Migration:

Acquisitions and mergers
An organisation may have been acquired by or merged with another, and this often requires them to migrate from an existing source tenant to an existing target tenant. In certain cases, you may find that instead of moving one tenancy into the other, they may instead opt to migrate both organisations into a new target tenant. This is common in circumstances where the conglomerate of the two organisations undergoes rebranding or if there are regulatory requirements associated with their merge.

Divestitures
When an organisation is subject to divestiture, and sections of the organisation are to be split away, this often results in a need to migrate select objects and content from an existing source tenant to a new target tenant.

Rebranding
During a rebranding exercise it might become a requirement to create a new tenant name to match the rebrand. This would typically involve migrating from an existing source tenant to a new target tenant.

Regulatory
An organisation may have to meet specific regulatory requirements that require them to migrate to a new tenant. In this case the organisation would migrate from an existing source tenant to a new target tenant.

The major benefit of Office 365 tenant to tenant migration is that you can move or migrate mailboxes from one tenant to another in Microsoft Office 365 with the complete mailbox data. The process is lengthy and complex, so I suggest you read each instruction carefully to avoid errors.

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