Receive notification about a colleague's status in Teams

If you want to know when someone in Teams changes their status to Available or Offline, you can add them to your list of status notifications from a previous chat or in settings.

Creating a status change notification via chat

The chat option is useful if you have recently had a one-on-one chat with the person about whom you want to receive notifications. 

1. Select  Chat on the left side of the app.
2. In your chat list, choose a one-on-one chat with the person about whom you want to receive a notification.
3. Select  More options and select  Sign up if available.
   
   
4. If you no longer want to see a person's status, follow the previous steps and select  Disable notifications.

Creating a status change notification in settings

The Settings option allows you to search for someone in your organization and add them directly to your list of notifications.

1. Select your profile image at the top right of Teams. Then select  Settings >  notifications to notification settings opening.
2. Select the button Edit to the right of Persons to Open the Manage Status Notifications screen.
   
   
3. Type in The Status Notifications screen manage the name of the person about whom you want to receive a notification in the Add People search box. Select the name when it is displayed.
   
   
4. To remove someone from your list of status notifications, follow the previous steps and then select the Disable button next to the name.
   

Source: Receive notification when someone's status changes to Teams (microsoft.com)

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