Add Shared Mailboxes in Office 365

In Office 365, you have the ability to create Shared Mailboxes, designed for when you have generic email accounts used by multiple users. Whilst you can create Shared Mailboxes without a licence, some restrictions apply:

They are not designed to be logged into directly, instead using permissions to grant other users access
Must be accessed through a supported application:
- Outlook 2013 and later
- Outlook 2016 for Mac and later
- Outlook for Mobile
- Outlook on the Web
Limited to 50GB (without a licence)
Users who access the mailbox must be licenced for Exchange Online

Create a Shared Mailbox

You can create Shared Mailboxes in the Microsoft 365 Admin Center.

Log into the Microsoft 365 Admin Center using global admin credentials for the tenant: https://admin.microsoft.com

Go to ‘Groups > Shared Mailboxes’ on the left-hand menu

Select Add a mailbox

Enter the Name and Email Address for the Shared Mailbox

Press Add

It may take a short while for the Shared Mailbox to be created. Please allow 30 minutes if the mailbox does not appear in the list straight away.

Assign Permissions over a Shared Mailbox

As there is no password for the Shared Mailbox, you instead need to assign the other users permissions to access the Shared Mailbox. These users must have their own user mailbox in Exchange Online.

Log into the Microsoft 365 Admin Center using global admin credentials for the tenant: https://admin.microsoft.com Go to ‘Groups > Shared Mailboxes’ on the left-hand menu
Select the Shared Mailbox to edit Next to Members, select Edit
Press Add Members
Tick the Checkbox next to each user to add Press Save

It is recommended to allow up to 4 hours for permissions to propagate across Office 365 services.

Access a Shared Mailbox

Before attempting to access a shared mailbox, you should ensure the Auto-Discover record is added to the associated domain which the mailbox was created on. You will be given this record during the process to add the domain to Office 365. If this record has not been added, you should first add the record with your domain host.

Outlook 2013 and later

Unless specifically set otherwise, a shared mailbox you have access to with automatically appear as a separate mailbox in Outlook. If permissions have only been applied recently, please allow up to 4 hours for it to appear.

In the case the mailbox does not appear automatically, Outlook is likely unable to pick up the mailbox settings. You should check that your domain has the Auto-Discover record in place.

Outlook 2016 for Mac and later

Outlook for Mac requires you to specify which additional accounts it should open.

Open Outlook for Mac Go to ‘Tools > Accounts’
Select Advanced
Select the Delegates tab
Under People I am a delegate for; click the + icon Search for and select the mailbox you want to add Press Add Press OK Close the Accounts window

The account will appear as a new mailbox alongside the primary.

Outlook for Mobile

If you access emails on your mobile and need access to a Shared Mailbox, you will need to use the Outlook for iOS or Outlook for Android applications.

Open the Outlook for iOS/Android application Open the Menu (click on the Home/Account icon or the Menu icon)
Select the Settings cog
Select Add Email Account Select Add Shared Mailbox
Select the Account that has permissions to access the Shared Mailbox Enter the email address of the Shared Mailbox Press Add Shared Mailbox

This will add the Shared Mailbox alongside your other accounts in Outlook for Mobile.

Outlook on the Web

If you need to access a Shared Mailbox when none of the above options are available, users can do so through the web portal using the Outlook on the Web application.

Log into your Office 365 mailbox at https://outlook.office.com

Click into your Account Profile Picture in the top corner

Select Open another mailbox

Search for and select the mailbox you want to open

Press Open

This will open the Shared Mailbox in a new tab/window in your web browser.