Slack Showing Everyone Offline? Your App Lost Its Connection

If Slack shows everyone as offline at the same time, your own Slack app has almost always lost its live connection to Slack. Your coworkers are probably still green. To refresh Slack, press Cmd + R on a Mac or Ctrl + R on Windows and Linux; in a browser, reload the tab. That reloads Slack without signing you out. If the grey dots come back, go to Help, Troubleshooting, Clear Cache and Restart, then check your VPN or proxy.

A whole workspace does not go idle in the same second. When every dot is grey at once, the thing that changed is on your side of the connection.

This guide explains how Slack presence moves between devices, what breaks, and how to fix it, step by step.

Why Slack shows everyone offline at once

Presence is live data. Your coworkers' Slack apps report their activity to Slack's servers. Slack decides active or away for each person and pushes each change to your app over a WebSocket, a connection that stays open while Slack runs.

When that connection drops, your app stops getting updates. Slack's own help center says that with WebSocket trouble "you won't automatically receive any new messages", and the same connection carries presence. The dots you see go stale or grey for everyone, including people who are typing right now. Common triggers:

• • Sleep and wake. Your laptop wakes up, but the Slack app does not reconnect cleanly.
• • Network changes. You switch Wi-Fi, join or leave a VPN, or tether to a phone.
• • A proxy, firewall, or security tool that allows normal web pages but blocks WebSocket traffic.
• • A Slack app bug. In late 2023, several r/Slack users on desktop version 4.35 reported that everyone showed offline in a workspace after switching between workspaces. One user said Slack support called it a known bug with a fix in progress, and the thread later confirmed it was fixed.
• • A Slack outage. Rare, but then everyone sees everyone as grey.

Fix it in this order

• Reload Slack. Press Cmd + R (Mac) or Ctrl + R (Windows, Linux). In a browser, reload the tab. This opens a fresh connection and fetches presence again. A user in the r/Slack thread above found that reloading fixed the workspace he was looking at.
• Look for a grey banner at the top of Slack, such as "Connecting..." or "Last updated less than a minute ago". Slack's help center lists that banner as the sign of WebSocket trouble.
• Clear the cache and restart. In the desktop app, open Help in the menu bar (the ☰ menu on Windows), choose Troubleshooting, then Clear Cache and Restart. Your messages and settings stay. Only the local copy is rebuilt.
• Check your VPN, proxy, and firewall. Turn off the VPN for a minute and reload. On a work network, ask IT to allow WebSocket connections to wss-primary.slack.com, wss-backup.slack.com, and wss-mobile.slack.com. Slack's help center names these three domains. On Windows, one r/Slack user fixed it by turning off Use a proxy server for your LAN in Internet Options.
• Check Slack itself. Open status.slack.com for an outage. Run the connection test at slack.com/help/test for problems on your network.
• Update or reinstall the app. If one workspace keeps going grey after you switch to it, you may be on a version with a presence bug. Install the latest version from Slack's site or your app store.

To check from a Mac or Linux terminal that your network lets the three WebSocket hosts through, test port 443 on each. We ran this on 7 October 2026 on a home network:

for h in wss-primary.slack.com wss-backup.slack.com wss-mobile.slack.com; do
  nc -z -G 5 "$h" 443 && echo "$h:443 open" || echo "$h:443 blocked"
done

wss-primary.slack.com:443 open
wss-backup.slack.com:443 open
wss-mobile.slack.com:443 open

A "blocked" line, or a long wait, on a work network or VPN means a firewall or proxy stops the connection that carries presence. Send IT the host names. An open port does not prove a proxy passes WebSocket traffic, but a blocked one settles it. (On Linux, use -w 5 instead of -G 5.)

If you use the Slack web app, try an incognito window with extensions off. Slack's help center suggests this because a browser extension can block the connection.

What each symptom means

What you see	Most likely cause	Fix
Everyone grey, in every channel	Your live connection dropped	Reload, then clear the cache
Everyone grey only in workspaces you switch to	Multi-workspace refresh bug	Reload each workspace, update the app
Everyone grey plus a grey banner	Network, VPN, or proxy blocks WebSocket	Ask IT to allow wss-*.slack.com
Your coworkers also see everyone grey	Slack outage	Wait, and check status.slack.com
Some people grey, some green	They are away	Nothing to fix

Slack has no offline state separate from away. A hollow grey dot means away, and our guide to Slack away status meaning covers every icon.

When Slack shows you offline to everyone else

The same broken connection works in the other direction. If your app cannot reach Slack, it cannot report your activity, and your dot goes grey for your team while you work. Fix it with the same steps above.

If your connection is fine and you still go grey, the cause is different. Slack sets you away after 10 minutes without keyboard or mouse input on the computer, when your computer sleeps, or when you leave the phone app. Those causes are in Slack keeps showing me away while working, and the rules are in how Slack decides when you are away.

A laptop that drops its VPN every hour will keep turning you grey. Slack Green keeps a Slack session active on its side instead of on your laptop, so VPN drops, sleep and reconnects do not turn your dot grey until your schedule ends. The other options are compared in how to keep Slack active.

Does Slack work without internet?

Partly. With no connection at all, the Slack desktop app still opens from files stored on your computer and shows conversations it loaded before. Slack's engineering team described the limits when they rebuilt the desktop client around a service worker: you can boot, read messages from conversations you have read before, and move your unread marker, which syncs once you are back online. Everything that needs Slack's servers waits for the connection:

The iPhone and Android apps show what they last loaded and do nothing else until the phone is back online.

Before a flight, schedule anything that must go out while you are in the air: click the arrow next to Send and pick a time, as in how to delay and schedule Slack messages. Open the conversations you will need so the app caches them, and set a status with an end time, such as "Flying, back online at 4pm".

On the phone

The Slack mobile app only keeps a live connection while it is on screen. When you open it, it reconnects and loads presence again, so a few seconds of grey dots right after you open it is normal. If the dots stay grey:

• Pull down on the channel list or close the app fully and open it again.

• On iPhone, turn off Low Data Mode for your Wi-Fi or cellular network. On Android, let Slack use unrestricted data when Data Saver is on. Then reopen Slack.

• Check that Slack can use mobile data and background data in your phone settings.

Your own dot on mobile turns grey as soon as you leave the app. That part is Slack's normal rule, covered in how to keep Slack active on your phone.

Some coworkers always show offline

If only a few people are always grey, nothing is broken. Two reasons cover most of them:

• They set themselves away by hand. Manual away stays on until they switch it back, and it looks the same as being signed out. That is how people appear offline on Slack on purpose.

• They only use Slack on their phone. Their dot is green only while the app is open on screen.

Slack also shows no "last seen" time, so a grey dot does not tell you if they left five minutes ago or last week. See does Slack show last seen.

FAQ

Why does Slack show everyone offline?

Your Slack app lost its live WebSocket connection, so it stopped getting presence updates. Reload with Cmd + R or Ctrl + R. If that does not help, use Clear Cache and Restart and check your VPN or proxy.

How do I refresh presence in Slack?

Reload the app with Cmd + R or Ctrl + R, or reload the browser tab. On mobile, close the app fully and open it again.

Is Slack down if everyone shows offline?

Usually not. Check status.slack.com. If there is no incident and your coworkers see green dots, the problem is your connection.

Why does my Slack keep going offline?

Your laptop sleeps, your network or VPN changes, or you do not touch the computer for 10 minutes. The first two drop the connection. The last one is Slack's away timer.