Microsoft 365 Shared Mailbox & Limitations

What is a Shared Mailbox?

A shared mailbox is a unique mailbox that is created by the Office 365 administrator to allow multiple users to send & receive messages from the same address. It allows companies to share the load of customer inquiries through emails. They can also be used to store the data that is migrated from on-premises public folders.

Shared mailboxes are not associated with individual users, and it is configured to be accessed by several users like the Sales team, Accounts team, HR, etc.

When you send a message from a shared mailbox, the other person will receive it from Shared mailbox, not from a specific user. Though a shared mailbox is created by the administrator, it has no owner and no password. However, a user must have permissions from the administrator to access a shared mailbox.

Also, shared mailboxes in Office 365 are free and doesn’t require a license – but, there are some limits to use shared mailboxes. For example, the size limit of a free shared mailbox is 50GB, and it cannot be used as a primary mailbox.

Limitations of a Shared Mailbox

Here are the limitations of a Shared Mailbox:

• It is absolutely free to use and doesn’t require a license, but users that access Shared mailboxes must be assigned with Office 365 licenses
• If you have Exchange Online Kiosk license, then you cannot access Shared Mailbox
• Every Shared Mailbox has a size limit of 50 GB, and if it exceeds that limit, then it needs to be licensed
• A shared Mailbox doesn’t have a Username or Password, and no one can sign into it directly. To access a shared mailbox, users need to sign into their own mailbox, and then open the shared mailbox.
• It cannot be used to archive emails from a user
• It cannot be used for Journaling
• It can only be accessed via Outlook desktop or Outlook Web Portal after it has been configured in a users account by the Administrator for the organisation