FUDforum 2.3 includes a private messaging (PM) system that if enabled via the global control panel allows forum members to send private messages to one another.

The private messaging system supports forwarding, the ability to send a message to multiple users and reply notifications. If allowed by the administrator, the users may also attach one or more files to their private messages. Just like in a mail client the sent messages are stored in a special folder, 'sent', so that the user can easily refer back to them if the need arises. There is also a 'drafts' folder where the user can keep their unfinished messages.

Via the private messaging controls administrator(s) can specify what features the users may use inside their private messages, as well as the amount messages the users can keep in their PM folders.