By default, when a Teams user makes a call to a PSTN phone, the phone number of the Teams user is visible. Likewise, when a PSTN caller makes a call to a Teams user, the PSTN caller's phone number is visible.
As an administrator, you can use caller ID policies to change or block the caller ID (also known as calling line ID). You can use caller ID policies to display an alternate phone number for Teams users in your organization, block the outbound phone number, block an incoming number from being displayed, or set the Calling Party Name (CNAM). For example, when a user makes a call, you can change the caller ID to display your organization's main phone number and company name instead of the user's phone number.
You can set a caller ID with a Ressource account number linked to either an autoattendant or callQueue using Powershell :
$RA_id = (Get-CsOnlineApplicationInstance -Identity autoattendantAA@domain.com).objectID
Set-CsCallingLineIdentity -Identity "Tag:Caller ID services" -CallingIDSubstitute Resource -EnableUserOverride $false -ResourceAccount $RA_id
Grant-CsCallingLineIdentity -Identity "firstname.lastname@example.org" -PolicyName "Tag:Caller ID services"
The following prerequisites are required before working with this feature:
Your users are Enterprise Voice enabled and have an own number assigned. With Microsoft Calling Plans, this means the user needs a calling plan. With Direct Routing, this means the user needs a number.
You have a resource account licensed with the license “Microsoft 365 Phone System – Virtual User” and a service number assigned to that account.