Migrating from one Exchange online tenant to another.


  • we are undergoing a company restructure and these a desire to split the company into 2 separate entities. we already have a O365 tenant and the New Arm will be functioning from a separate tenant. is there a way to transfer mailboxes between the tenants directly ?

    if so does the Data transferred stay in our retention ?

    if these not a we will fall back to doing PST exports but does this data stay in the Retention?

    Thanks in Advance. 

    Michael Groombridge 

    Wednesday, May 16, 2018 1:52 PM


  • No, there is not a direct method of moving mailboxes from one O365 tenant to another.  You will need to plan for a full migration of the domain/s from its' existing tenant to the other.

    Your retention policies will need to be reconfigured in the new tenant, as part of your migration planning.  If you have a 3rd party Journal, then that will also need to be reconfigured.

    There is nothing that allows for a coexistence, merge or migration between two O365 tenants.  It's always work.

    Data that was archived off...  I have a split answer because that depends on How it was "retained".  Normally it is expected that some meta data is stripped when content is compressed and archived.  Planning for proper archive migrations should be planned too because you might need some "re-hydration" of the objects.

    Wednesday, May 16, 2018 2:35 PM

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