Slack notifications are useful only when they actually reach you. Many people enable notifications inside Slack but still miss messages because macOS Focus, Windows Do Not Disturb, browser permissions, app sound settings, or channel-specific settings silently block alerts.

In your case, the issue was Focus / Do Not Disturb. That is one of the most common reasons Slack messages arrive without sound or banners.

1. First Understand How Slack Notifications Work

Slack has multiple notification layers:

1. Slack workspace notification settings
2. Slack sound and badge settings
3. Channel or DM-specific notification settings
4. Slack pause / Do Not Disturb schedule
5. macOS or Windows notification permissions
6. macOS Focus or Windows Do Not Disturb
7. Browser notification permissions, if you use Slack in Chrome, Edge, Firefox, or Safari
8. System sound output and volume

So the correct fix is not only “enable Slack notification.” You must check all layers.

2. Enable Slack Notifications for Every Message

Open Slack desktop app.

Go to:

Profile picture → Preferences → Notifications

Under How to notify you, enable:

• Desktop notifications
• Mobile notifications, if needed

Under What to notify you about, choose:

• Everything / All new messages

Slack officially allows users to choose whether they receive notifications for everything or only mentions and direct messages from the notification preferences page. (Slack)

Recommended setting if you want every message:

3. Enable Slack Sound and Message Preview

In Slack:

Profile picture → Preferences → Notifications → Sound & appearance

Enable or check:

• Include a preview of the message in each notification
• Make sure Mute all sounds from Slack is not enabled
• Select a sound for:
  • New messages
  • Direct messages
  • Huddles
  • VIP messages, if your plan supports it

Slack provides sound and appearance controls where you can choose message previews, mute or unmute Slack sounds, and select different sounds for notification types. (Slack)

You can also test sound from Slack:

Preferences → Sound & appearance → Show an example

Slack recommends using this option to send a test notification when troubleshooting sound problems. (Slack)

4. Enable Slack Badge Notifications

Badges help you see unread Slack activity on the app icon.

In Slack:

Profile picture → Preferences → Notifications → Sound & appearance

Enable:

• Show a badge on Slack’s icon to indicate new activity

Slack explains that unread notifications can show a badge on the Slack desktop icon, and this can be enabled or disabled from Sound & appearance. (Slack)

On Windows, Slack badges can appear in two places:

• Taskbar
• Notification area / system tray

Slack notes that Windows taskbar badges may not appear if the taskbar uses small taskbar buttons. (Slack)

5. Enable Channel-Specific Notifications

This is important: even if global Slack notifications are enabled, a specific channel can still behave differently.

Open the Slack channel.

Go to:

Channel name / Notifications icon → Notification settings

Choose:

• All new posts / All new messages

For group DMs or channels, Slack lets you choose All new posts or Just mentions from the conversation notification menu. (Slack)

Use this for your most important channels:

6. Check Muted Channels and DMs

A muted channel or DM will not alert normally.

Open the channel or DM.

Click:

Notifications icon → Unmute / Change notification setting

Slack allows users to mute channels and DMs from the notification icon, and muted conversations can be hidden or silenced. (Slack)

Check this especially if only one channel is not making sound.

7. Resume Slack Notifications if Paused

Slack has its own pause feature. This is separate from macOS Focus and Windows Do Not Disturb.

In Slack:

Profile picture → Pause notifications

If paused, click:

Resume notifications

Slack says that when notifications are paused, you will not receive notifications until they are resumed. Other users may also see a snooze icon next to your name. (Slack)

You can also use this command in Slack:

/dnd off

Slack supports slash commands like /dnd off to resume notifications. (Slack)

8. Check Slack Notification Schedule

Slack can pause notifications automatically outside your selected working hours.

Go to:

Profile picture → Preferences → Notifications → Notification schedule

Set:

• Allow notifications: Every day
• Start time: your preferred start time
• End time: your preferred end time

For maximum alerts, set a wide schedule, for example:

Every day: 00:00 to 23:59
Code language: CSS (css)

Slack notification schedule controls which days and hours notifications are allowed; outside that schedule, notifications are paused. (Slack)

Mac: Enable Slack Notifications and Sound

9. Check macOS Slack Notification Permission

On Mac:

Apple menu → System Settings → Notifications → Slack

Enable:

• Allow notifications
• Alert style: Banners or Alerts
• Play sound for notification
• Badge application icon
• Show previews, if required

Slack’s troubleshooting guide says macOS users should check Slack under Notifications and make sure Slack notifications are allowed and the alert style is set to Banners or Alerts. (Slack)

Apple also documents that macOS notification settings are managed from System Settings → Notifications. (Apple Support)

10. Disable Focus / Do Not Disturb on Mac

This was your actual issue.

On Mac:

1. Click Control Center in the top-right menu bar
2. Click Focus
3. Make sure Do Not Disturb is Off

Or go to:

Apple menu → System Settings → Focus

Check every Focus profile, such as:

• Do Not Disturb
• Work
• Sleep
• Personal
• Gaming
• Custom Focus modes

Make sure Slack is not blocked.

Slack specifically says to check macOS Do Not Disturb if notifications are not delivered. (Slack)

Apple explains that Focus can control which app notifications are allowed, and Focus modes can also be scheduled automatically by time, location, or app usage. (Apple Support)

Recommended Mac setting:

Important: if Focus sync is enabled across Apple devices, turning on Focus on iPhone can also affect Mac notifications. Tiny Apple ecosystem trap. Very annoying, very real.

11. Check Mac Sound Output

If banners appear but no sound plays:

Go to:

Apple menu → System Settings → Sound

Check:

• Output device is correct
• Volume is not muted
• Alert volume is high enough
• Sound effects are playing through the correct device

Slack recommends checking macOS sound effects output and alert volume when Slack notification sounds are not working. (Slack)

Windows: Enable Slack Notifications and Sound

12. Enable Windows Notifications for Slack

On Windows 11:

Start → Settings → System → Notifications

Enable:

• Notifications
• Find Slack
• Turn Slack notifications On
• Enable:
  • Show notification banners
  • Show notifications in notification center
  • Play a sound when a notification arrives

Microsoft explains that Windows notifications can appear as banners and in notification center, and individual apps can be configured for banners, notification center visibility, sound, priority, and number of notifications. (Microsoft Support)

Slack also recommends checking Windows notification settings and confirming Slack has Play a sound enabled. (Slack)

13. Disable Windows Do Not Disturb

On Windows 11:

Start → Settings → System → Notifications

Turn off:

• Do not disturb

Also expand:

Turn on do not disturb automatically

Disable or review these automatic rules:

• During certain times
• When duplicating display
• When playing a game
• When using an app in full-screen mode
• For the first hour after a Windows feature update

Microsoft says Windows Do Not Disturb silences notifications and can turn on automatically under these conditions. (Microsoft Support)

This is the Windows version of the same problem you had on Mac.

14. Check Windows Focus Sessions

Windows Focus can automatically enable Do Not Disturb.

Check:

Settings → System → Focus

When a Focus session starts, Windows turns on Do Not Disturb automatically, and if Do Not Disturb was already on before the session, it can remain on afterward. (Microsoft Support)

Recommended Windows setting:

15. Keep Slack Running in Windows Notification Area

If Slack is closed completely, notifications may not behave as expected.

In Slack on Windows:

Profile picture → Preferences → Advanced

Check:

• Leave app running in notification area when the window is closed

Slack says that by default the app can keep running in the Windows notification area when the window is closed; disabling that removes the Slack icon and badges from the notification area. (Slack)

Also check:

Preferences → Notifications → Flash window when a notification is received → Always

Slack provides this option for Windows taskbar flashing. (Slack)

Browser-Based Slack Notifications

Use this section if you open Slack in a browser instead of the desktop app.

16. Chrome Notification Permission

In Chrome:

1. Open your Slack workspace in Chrome
2. Click the site information icon near the address bar
3. Open Site settings
4. Set Notifications to Allow

Google Chrome allows site notifications from the site information menu by turning on Notifications for that site. (Google Help)

Slack also says Chrome users should check Privacy and security → Site settings → Notifications and allow sites to ask for notifications. (Slack)

17. Microsoft Edge Notification Permission

In Edge:

Settings → Cookies and site permissions → Notifications

Make sure your Slack workspace is in the Allow section.

Slack’s troubleshooting guide says Edge users should check Cookies and site permissions and confirm Slack is allowed under Notifications. (Slack)

18. Firefox Notification Permission

In Firefox:

Settings / Preferences → Privacy & Security → Permissions → Notifications → Settings

Make sure your Slack workspace is allowed.

Slack’s troubleshooting guide says Firefox users should confirm the Slack workspace is included in the notification permissions list. (Slack)

19. Safari Notification Permission on Mac

In Safari:

Safari → Settings → Websites → Notifications

Make sure your Slack workspace is allowed.

Apple documents Safari website notification controls under Safari → Settings → Websites → Notifications. (Apple Support)

Slack also notes that browser users only receive notifications for workspaces open in the browser. (Slack)

Quick Troubleshooting Checklist

Use this when Slack message sound is not working.

Best Recommended Setup for You

Since your issue was Focus / Do Not Disturb, use this setup:

On Mac

1. Control Center → Focus → Off
2. System Settings → Focus
3. Open each Focus mode
4. Remove automatic schedules if not needed
5. Add Slack to allowed apps if you still want to use Focus
6. System Settings → Notifications → Slack
7. Enable:
   • Allow notifications
   • Banners or Alerts
   • Play sound
   • Badge app icon

In Slack

1. Profile picture → Preferences → Notifications
2. Set notification type to Everything
3. Under Sound & appearance, make sure Slack sounds are not muted
4. Select a clear notification sound
5. For important channels, set All new posts
6. Make sure notifications are not paused
7. Set notification schedule to your working hours or all day

Final Fix Order

When Slack sound is not working, follow this order:

1. Check macOS Focus / Windows Do Not Disturb
2. Check Slack is not paused
3. Check Slack notification setting = Everything
4. Check Slack sound is enabled
5. Check OS notification permission
6. Check channel-specific notification setting
7. Check browser permission, if using browser
8. Restart Slack

Most of the time, the villain is not Slack. It is Focus, Do Not Disturb, notification schedule, or channel-specific mute quietly sitting there like “nothing to see here.”

Rajesh Kumar

I’m a DevOps/SRE/DevSecOps/Cloud Expert passionate about sharing knowledge and experiences. I have worked at Cotocus. I share tech blog at DevOps School, travel stories at Holiday Landmark, stock market tips at Stocks Mantra, health and fitness guidance at My Medic Plus, product reviews at TrueReviewNow , and SEO strategies at Wizbrand.

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