How to rename an Office 365 Mailbox

Overview

This article will describe how to change the primary address of an Office 365 mailbox.  This can be used in the case where a staff member is being replaced with another and you wish to keep the same license, files and email.

Prerequisite

Password for your Microsoft 365 email account.

Instructions

1. Login to the 365 admin panel for at https://portal.office.com
2. Access the admin Center by clicking the menu on the top left and selecting admin:
   
3. Select the user and press “manage username”:
   
   NB: If you do not have this option you will need to speak to your M365 License provider or System Administrator.
4. Change the username as to the new email account.
5. Optionally, you can also add the old username as an alias to the new account. To do so, select “Managed email aliases”.
6. Then, add the old username in as an alias:
   
7. Select “Manage contact information”:
   
8. Update the First name, last name and Display name for the new user.
9. Change the password and you’re good to go.