Slack Notifications Not Working on Mac? Check These Settings

If Slack notifications are not working on your Mac, open System Settings > Notifications > Slack and check that Allow notifications is on and the alert style is Banners or Alerts. Then check Focus in Control Center: a Focus mode, or a Focus shared from your iPhone, blocks Slack unless it is on the allowed list. The third cause catches people in meetings: macOS hides all notifications while you mirror or share your screen, unless you turn that off. If all three are right, the cause is inside Slack. The most common one we found is Slack's own working hours, which pause every notification after 5 PM and at weekends unless you change them.

We checked the Slack settings on this page on 1 October 2026 in Slack 4.52.162 for Mac on macOS 26.5.2, and in the same account in a browser. Slack also decides where to send each alert from your activity: it holds phone alerts while you look active on the desktop.

Find the cause from what you see

Fix 1: allow Slack in macOS notification settings

• Open System Settings > Notifications.
• Click Slack in the application list. If Slack is missing, open Slack once and send yourself a test message so macOS registers it.
• Turn on Allow notifications.
• Set the alert style to Banners (they disappear by themselves) or Alerts (they stay until you click). None sends alerts to Notification Center without showing them.
• Turn on Play sound for notification and Badge application icon.

At the top of the same page, Show previews decides whether the message text appears. If it is set to Never, banners still arrive but only say Slack.

Fix 2: check Focus and Focus shared from your iPhone

A Focus mode (Do Not Disturb, Work, Personal, Sleep) silences every app not on its allowed list. The Focus icon in the menu bar or Control Center shows which one is on.

• • Allow Slack in a Focus: System Settings > Focus, pick the Focus, open Allowed Notifications, and add Slack under Apps.
• • Focus schedules: a Focus can turn on by itself at set times, or when you open a certain app. If Slack goes quiet at the same time each day, look at the schedule in that Focus.
• • Share across devices: with this on, a Focus you start on your iPhone also silences your Mac. Turn it off at the bottom of System Settings > Focus if your phone's Sleep Focus is muting your work Mac in the morning.

Fix 3: notifications while you share or mirror the screen

This one is Mac-specific and is off by default. In System Settings > Notifications, under the notification center options at the top, turn on Allow notifications when mirroring or sharing the display. With it off, no banner appears while you share your screen in Zoom, Teams, Google Meet or a Slack huddle, or while you use AirPlay to a TV. That default protects you from showing a private message to a meeting, so turn it on only if you need alerts while you present. Two neighbours in the same list control alerts when the display is sleeping and when the screen is locked.

If sharing the screen in a Slack huddle fails altogether, the macOS permission behind it is covered in Slack screen sharing not working on Mac.

Fix 4: the Slack settings

If macOS lets Slack through and nothing arrives, look inside Slack. Click your profile picture and choose Preferences (Cmd+, in the desktop app).

Availability > Working hours is the first place to look. The text under it says it plainly: "You'll only receive notifications in the hours you choose. Outside of those times, notifications will be paused." In our account it was set to Weekdays, 9:00 AM to 5:00 PM, and the line below it read "You won't receive notifications on Saturday or Sunday".



Slack turns those hours into a notification pause. The dnd.info API for the same account, called at 4:20 PM Seoul time, returned (trimmed):

{
  "dnd_enabled": true,
  "next_dnd_start_ts": 1790841600,
  "next_dnd_end_ts": 1790899200
}

Those timestamps are 5:00 PM that day and 9:00 AM the next morning in Seoul: the working hours, to the minute. During the pause a small z sits on your profile picture and no banner reaches the Mac. Widen the hours, or choose Resume notifications from the profile menu for one evening. Why a pause keeps coming back is in why does Slack pause my notifications.

Then open Notifications in the same window:

• • Desktop notifications must be ticked under "How to notify you".
• • What to notify you about. "Mentions and direct messages" stays silent for normal channel messages. A channel can also be set to mute on its own.
• • The conversation on screen. Slack does not banner a message in the conversation you already have open and in front.
• • Threads. Replies alert you only when Thread replies is ticked and you follow the thread; see Slack thread notifications not working.

Every in-Slack check, with the settings on iPhone, Android and Windows, is in the main guide, Slack notifications not working.

Fix 5: no notification sound on Mac

A banner with no sound has three possible switches:

In Slack, Preferences > Notifications > Sounds & appearance: Mute all messaging sounds from Slack must be unticked. Sound choices are in how to change the Slack notification sound.

In macOS, System Settings > Notifications > Slack > Play sound for notification must be on.

The Mac's output: check the volume and System Settings > Sound > Output. If headphones or a monitor with speakers are connected, the sound may be going there. A Focus mode also silences sounds for apps it blocks.

The desktop app keeps these choices in a file on your Mac, one entry per workspace, so you can check them from Terminal without opening Slack:

python3 -c "import json,os; s=json.load(open(os.path.expanduser('~/Library/Application Support/Slack/storage/root-state.json'))); [print(t, p.get('notificationPrefs')) for t,p in s['webapp']['teams'].items()]"

On our Mac it printed one line per signed-in workspace (workspace ID hidden here):

T0XXXXXXXXX {'notificationSound': 'knock_brush.mp3', 'noTextInNotifications': False, 'muteSounds': False}

muteSounds: True means the mute box is ticked for that workspace, and noTextInNotifications: True means banners hide the message text. The sound file named there, knock_brush.mp3, is one of 23 sounds inside /Applications/Slack.app/Contents/Resources, so a missing sound is a setting, not a missing file.

Fix 6: Slack must be running

On a Mac, clicking the red close button hides the Slack window, and alerts keep coming. Cmd+Q or Slack > Quit Slack stops it, and no alerts arrive until you open it again. To start it every day, right-click Slack in the Dock and choose Options > Open at Login, or add it in System Settings > General > Login Items & Extensions.

If you use Slack in Chrome or Safari instead of the app, the browser needs its own permission: System Settings > Notifications > Google Chrome (or Safari), plus the site permission for app.slack.com in the browser. The tab must stay open. The trade-offs are in Slack desktop app vs browser.

Fix 7: reset Slack and Notification Center

When every setting is right and alerts still do not show:

In Slack, open Help > Troubleshooting > Clear Cache and Restart.

Update Slack: Slack > Check for Updates, or the App Store if you installed it there.

Restart Notification Center, or quit and reopen Slack, from Terminal:

# restart the macOS notification service; it starts again by itself
killall NotificationCenter

# quit Slack cleanly, then open it again
osascript -e 'quit app "Slack"' && sleep 2 && open -a Slack

Restart the Mac if banners from other apps are missing too. That points to macOS, not Slack.

When the Mac gets the alert and the phone does not

That is the Slack timing rule. By default Slack sends phone alerts only after you have been inactive on the desktop for a while, so a Mac that looks active keeps the phone quiet. Change it in Preferences > Notifications, under "When you're not active on desktop... Send notifications to my mobile devices". Ours was set to As soon as I'm inactive; pick Immediately if you want both. The iPhone side is in keep Slack active on iPhone.

The phone side, including Scheduled Summary and quiet alerts, is in Slack notifications not working on iPhone.

FAQ

Why do my Slack notifications stop at 5 PM? Slack's working hours, under Preferences > Availability, pause notifications outside the hours set there. Ours were Weekdays 9:00 AM to 5:00 PM, and Slack scheduled the pause for exactly 5:00 PM.

Why do Slack notifications stop when I share my screen? macOS hides alerts while you share or mirror the display. Turn on Allow notifications when mirroring or sharing the display.

Do I get Slack notifications if I close the Slack window on Mac? Yes. Closing the window keeps Slack running. Quitting with Cmd+Q stops all alerts.

Why is there no Slack notification sound on my Mac? Mute all messaging sounds is ticked in Slack, Play sound is off for Slack in macOS, or the sound goes to another output.