The two ways to add people to Slack conversations

You can add someone to a Slack conversation in two ways: by inviting them to a channel (which is public or private, and stays open for future messages) or by adding them to a direct message thread (which is just between specific people). The method you use depends on whether you want the person to see the entire conversation history or just join going forward, and whether other people need to see this exchange.

Channels are best when multiple people need to collaborate on the same topic over time. Direct messages are best when you want a focused conversation with one person or a small group, and you do not need a permanent record that others can search later. Slack also lets you add people to an existing direct message, which creates a group conversation.

Key Takeaways

  • To add someone to a channel, open the channel, click the plus icon next to the member count at the top, search for the person's name, and click "Add".
  • When you add someone to a channel, they see all past messages in that channel, not just messages from the moment they join.
  • To add someone to a direct message conversation, open the conversation, click the plus icon next to the member names at the top, and search for the person you want to add.
  • Private channels require the channel owner or an admin to approve new members, while public channels let anyone add people.
  • Once someone is added to a channel or group conversation, they receive a notification that they have been added.

Adding someone to a public or private channel

Open the channel where you want to add the person. At the top of the screen, you will see the channel name and a small icon showing the number of members (it looks like a person with a plus sign, or just shows a number). Click that icon.

A panel will open on the right side showing the current members of the channel. Near the top of that panel, you will see a field that says "Add members" or shows a plus sign. Click it, then type the person's name or email address. Slack will show you matching names as you type. Click the person's name when you see them in the list.

If the channel is private, the owner or an admin may need to approve the addition. If the channel is public, the person is added when ready and will see a notification that they have been added to the channel. They will also see all the messages that were posted in that channel before they joined.

Adding someone to a direct message or group conversation

Open the direct message or group conversation where you want to add the person. At the top of the screen, you will see the name or names of the people in the conversation. Next to those names, there is usually a plus icon or an "Add member" button. Click it.

A search field will appear. Type the person's name or email address. When you see them in the list, click their name to add them. The person will receive a notification that they have been added to the conversation, and they will see all the messages from that point forward. Unlike channels, they will not see messages that were sent before they were added to the group conversation.

What happens when someone is added to a conversation

When you add someone to a channel, they receive a notification in Slack saying they have been added. They can then open the channel and see all past messages. This is useful when you want someone to understand the full context of a discussion that has already been happening.

When you add someone to a direct message group, they also get a notification, but they only see messages sent after they join. This is different from channels, where new members can scroll back and read everything. If you need the new person to see earlier messages in a group conversation, you may want to copy and paste key messages or summarize what they missed.

Removing someone from a conversation

If you need to remove someone from a channel, open the channel, click the member icon at the top, find the person's name in the list, and click the X or "Remove" button next to their name. You must be the channel owner or an admin to remove someone from a private channel. In a public channel, any member can usually remove others, though your workspace admin can change this setting.

To remove someone from a direct message group, open the conversation, click the member icon at the top, find their name, and click the X next to it. The person will no longer see the conversation, and they will not receive new messages in that thread.

Permissions and who can add people

In most Slack workspaces, any member can add people to a public channel. For private channels, only the channel owner or someone with admin permissions can add new members. Your workspace admin controls these settings, so if you cannot add someone to a private channel, ask your admin or the channel owner for help.

If someone is not showing up in the search when you try to add them, they may not be part of your Slack workspace yet. Only people who have been invited to your workspace can be added to channels or conversations. If you need to add someone from outside your organization, your workspace admin must first send them an invitation to join the workspace.

Frequently Asked Questions

Can I add someone to a channel if they are not in my Slack workspace?

No. The person must already be a member of your Slack workspace before you can add them to any channel or conversation. If they are not in your workspace, ask your workspace admin to send them an invitation first. Once they accept and join, you can then add them to channels.

Will the person see old messages when I add them to a channel?

Yes, they will see all messages that were posted in that channel before they were added. This is one reason channels are useful for ongoing projects — new team members can read the full history. In group direct messages, they only see messages from the moment they join.

What if I add someone to a channel by mistake?

You can remove them by opening the channel, clicking the member icon at the top, finding their name, and clicking the X next to it. They will be removed from the channel and will no longer see new messages there. They can always be added back later if needed.

Do I need permission to add someone to a direct message?

No. You can add anyone in your workspace to a direct message group conversation without asking permission. However, they will receive a notification that they have been added, so they will know the conversation exists.

Can I add multiple people to a channel at once?

Most versions of Slack let you add one person at a time through the member panel. If you need to add many people, you can repeat the process, or ask your workspace admin if bulk-invite features are available in your plan.