Information Services Division


Shared mailboxes

A shared mailbox allows a group of users to read/send emails and share calendars from a common mailbox. They work in the same way as your own UCL account except they are managed by several users.

Reasons for using a Shared Mailbox

  • Organise and control your mail within a single mailbox for multiple users to access.
  • Provides a clearly defined email address to receive enquiries, or to send out communications from.
  • A single copy of the email is stored, as opposed to multiple copies when distribution lists are used.
  • Shared mailboxes are separate from your personal account, freeing up your personal quota space.
  • The shared mailbox is more convenient for archiving, and allows members who have recently joined the team or initiative to catch up with previous activities.


  • A separate mailbox on the live @ UCL system and has a specific email address associated with it i.e example@ucl.ac.uk
  • Identical to a user's mailbox, containing the standard folders; Inbox, Sent, Calendar, Contacts and Tasks.
  • Can be set up to allow authorised users to Send on Behalf of or Send As (with owner approval).

Naming Convention

Shared mailboxes will be prefixed with the Departmental Name, followed by the purpose of the mailbox (e.g. ISD.Shared Mailbox Name). This name will be visible to all live @ UCL users within the global address book (known as the Global Address List or GAL) and will be automatically added to the 'From' field for messages sent from the account.


To request a shared mailbox, log in to the ISD IT Services Portal and select the Shared Mailbox Request form. To action the request the following information would be required:

  • Reason for the shared mailbox (such as a project or job share)
  • Department associated with the shared mailbox
  • Name of the shared mailbox. The naming convention is Dept Name.Mailbox Name (e.g. ISD.Example Mailbox).
  • List of Owners (preferably their UCL userIDs or email address)
  • Members who require Read only permissions (preferably their UCL userIDs or email address)
  • Members who require Send on Behalf permissions (preferably their UCL userIDs or email address)

Shared mailbox requests will need to be approved by a Computer Rep registered within your department. A list of Computer Reps can be found on the Computer Reps Tool. Please ensure that you have included email authorisation from the Computer Rep within the request.


Access to a shared mailbox is controlled by four security groups, known as Owner, Send On Behalf, Send As and Read Only. Owners of the mailbox can change the membership of these groups themselves by using Outlook or OWA. The level of permission these security groups grant to the mailbox is further defined below:

  • Owner:  Administrators of the shared mailbox. Owners have Full Access permissions and can Send On Behalf of the mailbox. Owners can also change the membership to the mailbox's access groups.
  • Send on Behalf: Members of the Send on Behalf access group have Full Access permissions and can Send on Behalf of the mailbox.
  • Send As: Full Access to the mailbox and can Send As the mailbox.
  • Read Only: Full Access to the mailbox but cannot send messages from the mailbox.

Send On Behalf vs Send As

When an individual who has been granted Send on Behalf permission to a shared mailbox sends an email, the 'From' header will be displayed as 'User On Behalf Of Shared Mailbox Name' (e.g. Bloggs, Joe On Behalf Of ISD.Shared Mailbox Name). If someone with Send As permission sends an email, the 'From' header will be displayed as the shared mailbox name only (e.g. ISD.Shared Mailbox Name). As the original sender will not be visible within the headers, Send As access should be discussed with the owner of the shared mailbox first.

Security groups

Shared mailbox security groups follow the naming format of the greater-than symbol (>), followed by the mailbox name and the level of permission:

Level of AccessSecurity Group Name FormatExample
Owner>Dept.MailboxName.Owners.SG.SM.RoleAccountUserID>ISD.Shared Mailbox Name.Owners.SG.SM.xxxxxx
Send On Behalf>Dept.MailboxName.SendOnBehalf.SG.SM.RoleAccountUserID>ISD.Shared Mailbox Name.SendOnBehalf.SG.SM.xxxxxx
Send As>Dept.MailboxName.SendAs.SG.SM.Role AccountUserID>ISD.Shared Mailbox Name.SendAs.SG.SM.xxxxxx
Read Only>Dept.MailboxName.ReadOnly.SG.SM.RoleAccountUserID>ISD.Shared Mailbox Name.ReadOnly.SG.SM.xxxxxx

Please refer to the Permission Model [PDF] for a graphical representation of type of security groups created and the permissions associated with them.  For any additional help with permissions or security groups, please contact the ISD IT Services.

How-to guides

Outlook Web Access

Outlook 2016 for Windows

Outlook 2017 for macOS