Slack Activity Tab: What Lands There, the Filters, and Why You Cannot Hide It

The Activity tab is the bell in the left rail of Slack. It is one feed of everything that asks for your attention: mentions, reactions to your messages, replies in threads you follow, reminders, and, if you want them, DMs and busy channels. You cannot hide the tab itself; Slack locks it on. You can choose what else goes into it and build filtered views on top of it. On 7 October 2026 we sent a test account one @mention and one /remind, then opened every Activity setting in Slack for web to see where each item landed.

What showed up in Activity

The reminder went to Activity, and the To-dos tab in the rail got a badge at the same time. It did not come as a Slackbot DM: the DM with Slackbot had no new message after the reminder fired. Slack reminder not working covers what to check when one seems to be missing.

The rail badge on the bell counts unread Activity items. It went from 2 to 3 to 4 as our test items came in.

The tabs and filters at the top

The default tabs are All, DMs, Mentions and Threads, each with its own unread count. Next to them:

• • Unreads shows only items you have not opened.
• • The filter button opens a panel. "Notifications from" defaults to People, apps, and agents. Below it are checkboxes for DMs, Mentions, Threads, Channels set to "all new posts", Reactions, Invitations, Apps and Reminders, and under Additional Filters: VIP, Cleared items, and Specific channel or section.
• • Create Custom View at the bottom of that panel saves the ticked filters as a new tab.
• • The + after the tabs suggests ready-made views (Unreads, Reactions, and Starred from your sidebar) or Create a custom view.
• • Two buttons on the right switch between a card layout and a compact list.


A custom view is the closest thing to a quieter Activity tab. A view with only Mentions and Reminders ticked, for example, drops reactions and channel posts without changing any notification setting.

Can you hide or remove the Activity tab?

No. In Preferences > Navigation the list "Configure these tabs in the navigation bar" has a checkbox for each rail tab. Slackbot, Home and Activity are ticked and greyed out; only DMs, Files, To-dos and Agents & tools can be switched off. We checked the page code too: those three checkboxes are disabled, not only drawn grey.

The same page has Navigation Tab Appearance. "Icons only", in Slack's words, "makes navigation tabs smaller, and automatically turns off numerical badges". That is the closest built-in option to hiding the Activity count: the bell stays, the number goes.

Choosing what goes into Activity

The gear at the top right of the Activity tab opens Preferences > Notifications. Near the bottom is a section called What to show in Activity, with this line: "You'll always see mentions, reactions, and thread replies." Three things are optional, and all three were ticked in our account:

The second checkbox explains our "Post in #w7_underscore" card. Each test channel's bell in the header read "All new posts", so every new post in it went to Activity. To keep a busy channel out of Activity, set that channel to "Just mentions" from the bell in its header, or mute it; how muting works has the details. To read everything unread in one list instead, Slack has a separate All unreads view.

FAQ

Why do I see items from a channel I never get notified about? Check the channel's bell. If it says "All new posts", its posts go to Activity while the "Channels with notifications set to All new posts" box is ticked.

What does Mark Complete do to the reminder card? The card stays in Activity, greyed out with a tick, and stops counting as unread: our All count went from 5 to 4 and the To-dos badge went away. The reminder itself moved to the completed list (saved.list showed it as completed).

Where do reminders on a single message go? A reminder set from a message's menu (Remind me about this) also fires into Activity; see Slack remind me about this message.