Reserved names

A tenant's owners and admins can keep names back, so members cannot take addresses such as ceo@, hr@ or payroll@ on the tenant's domains for themselves. Only owners and admins give those addresses out.

What a reserved name stops

A reserved name is the part before the @. On every one of the tenant's own domains, a member cannot take it:

on the tenant's join page, when choosing their address;
as their own alias in webmail (Settings → Aliases);
as an extra mailbox they add for themselves in webmail (Settings → Extra mailboxes).

They are told the address is not available and to choose another. Names are matched whole: reserving hr does not stop hr.team@ or amy.hr@. Plus addressing still works on an address that exists: hr+jobs@ reaches hr@.

Owners and admins (in the tenant manager), staff and the API still create mailboxes, aliases and lists with reserved names. Addresses that already exist are not touched when a name is reserved.

The platform keeps its own list too, such as postmaster, abuse and support. Nobody can take those on the join page, or on the platform's shared domains. A tenant's list adds to it; it cannot take names off it.

Choosing the names

In the tenant manager (/manage), open Settings → General, card Reserved names, put one name per line and Save. The card shows the platform's names too. Names use letters, digits, ., _ and -, and are kept in lower case; up to 1000. Clear the box and save to reserve nothing.

Only owners and admins see the card and change the list.

Through the API

The list is reservedLocalParts in the team settings (GET and PATCH /v1/tenants/{tenantId}/team-settings). A PATCH sends the whole list, and [] clears it. platformReservedLocalParts (read only) is the platform's list.

{"reservedLocalParts": ["ceo", "finance", "hr", "payroll"]}