Admin-Managed Shared Mailbox Access in Nextcloud Mail

[Bytrider]

Is your feature request related to a problem? Please describe.

In organizational environments (e.g. associations, SMEs, healthcare facilities, schools), email communication is often based on shared mailboxes such as info@, support@, or office@.

Currently, shared mailboxes in Nextcloud Mail must be manually configured per user and per client.
There is no central administrative interface to:

• Define shared mailboxes
• Assign users to mailboxes
• Control access and sending permissions centrally

This results in:

• High administrative overhead
• Inconsistent configurations
• Increased error rates, especially during onboarding/offboarding

Describe the solution you'd like

Extend Nextcloud Mail with an admin-level mailbox management interface that allows administrators to:

• Centrally define shared mailboxes (email address / IMAP account)
• Assign users to those mailboxes
• Define per-user permission levels:
  • 🔍 Read-only
  • ✉️ Send
  • 🔧 Full access
• Control mailbox visibility and sending rights independently from a user’s personal email setup

This feature should integrate into the existing Nextcloud account and permission model.

Describe alternatives you've considered

• Centralized management of shared mailboxes
• Reduced setup and support effort
• Clear role-based email access
• Improved suitability for multi-user organizations

Additional context

• Group-based mailbox assignment
• Audit log for mailbox access
• API support for automated provisioning

[ChristophWurst]

I'm tagging this feature request as accepted. Some of this feature will require a mail server that supports the specific use case.