Channel privacy settings

Channels organize conversations based on who needs to see them. For example, it is common to have a channel for each team in an organization. Because Zulip further organizes messages into conversations labeled with topics, there is generally no need to create dedicated channels for specific projects.

Zulip supports a few types of channels:

• Public (): Members can join and view the complete message history. Public channels are visible to guest users only if they are subscribed (exactly like private channels with shared history).

• Private (): New subscribers must be added by an existing subscriber. Only subscribers and organization administrators can see the channel's name and description, and only subscribers can view topics and messages with the channel:

  • In private channels with shared history, new subscribers can access the channel's full message history.
  • In private channels with protected history, new subscribers can only see messages sent after they join.

• Web-public (): Members can join (guests must be invited by a subscriber). Anyone on the Internet can view complete message history without creating an account.

Privacy model for private channels

At a high level:

• Organization owners and administrators can see and modify most aspects of a private channel, including the membership and estimated traffic. Owners and administrators generally cannot see private channel messages or do things that would give them access to private channel messages, like adding new subscribers or changing the channel privacy settings.

• Organization members and moderators cannot easily see which private channels exist, or interact with them in any way until they are added. Given a channel name, they can figure out whether a channel with that name exists, but cannot see any other details about the channel.

• From the perspective of a guest, all channels are private channels, and they additionally can't add other members to the channels they are subscribed to.

There are two situations in which an organization owner or administrator can access private channel messages:

• Via some types of data export.

• Owners and administrators can change the ownership of a bot. If a bot is subscribed to a private channel, then an administrator can get access to that channel by taking control of the bot, though the access will be limited to what the bot can do. (e.g., incoming webhook bots cannot read messages.)

Detailed permissions

Public channels

✔Always

◾If subscribed to the channel

✶ Configurable. See Channel posting policy, Configure who can add users, and Configure who can remove users for details.

Private channels

✔Always

◾If subscribed to the channel

✶ Configurable, but at minimum must be subscribed to the channel. See Channel posting policy, Configure who can add users, and Configure who can remove users for details.

Related articles

• User roles
• Channel sending policy
• Web-public channels