Convert a user mailbox to a shared mailbox - Microsoft 365 Print

Convert to shared mailbox allows you to convert the user's mailbox to a shared mailbox. You might do this if the person leaves your organization and you want to keep their mailbox data around for a while.

When you convert a user's mailbox to a shared mailbox, all of the existing email and calendar is retained. Only now it's in a shared mailbox where several people will be able to access it instead of one person. At a later date, you can convert a shared mailbox back to a user (private) mailbox.

Use the Classic Exchange admin center to convert a mailbox

1. Go to the Classic Exchange admin center.
2. Select Recipients > Mailboxes.
3. Select the user mailbox. Under Convert to Shared Mailbox, select Convert.

If the mailbox is smaller than 50 GB, you can remove the license from the user, and stop paying for it. Don't delete the user's account. The shared mailbox needs it there as an anchor. If you're converting the mailbox of an employee that's leaving your organization, you should take additional steps to make sure that they can no longer log in.

Use the New Exchange admin center to convert a mailbox

1. Go to the Exchange admin center.
2. Select Recipients > Mailboxes.
3. Select the user mailbox. In the Mailbox tab, under More Actions, select Convert to shared mailbox.

If the mailbox is smaller than 50 GB, you can remove the license from the user, and stop paying for it. Don't delete the user's account. The shared mailbox needs it there as an anchor. If you are converting the mailbox of an employee that is leaving your organization, you should take additional steps to make sure that they cannot log in anymore.

Convert the mailbox of a deleted user

After deleting a user account, follow these steps to convert their old mailbox to a shared mailbox:

1. Restore the user's account.
2. Make sure a Microsoft 365 license is assigned to it.
3. Reset the user's password.
4. Wait 20-30 minutes for their mailbox to be re-created.
5. Once the mailbox is re-created, remove the license from the user's mailbox. Don't delete the user's old mailbox. The shared mailbox needs it there as an anchor.
6. Add members to the shared mailbox.

Convert a shared mailbox back to a user's (private) mailbox

1. Go to the Exchange admin center.
2. Select Recipients > Shared.
3. Select the shared mailbox. Under Convert to Regular Mailbox, select Convert.
4. Go back to the admin center. Under Users, choose the user account associated with the old shared mailbox. Assign a license to the account, and then reset the password.

It will take a few minutes for the mailbox to get set up, but after that, the person who's going to use that account is ready to go. When they sign in, they'll see the email and calendar items that used to be in the shared mailbox.