Change the phone numbers on your Audio Conferencing bridge
When you buy Audio Conferencing licenses, Microsoft is hosting your audio conferencing bridge for your organization. The audio conferencing bridge gives out dial-in phone numbers from different locations so that meeting organizers and participants can use them to join Skype for Business or Microsoft Teams meetings using a phone.
In addition to the phone numbers already assigned to your conferencing bridge, you can get additional service numbers (toll and toll-free numbers used for audio conferencing) from other locations, and then assign them to the conferencing bridge so you can expand coverage for your users.
To be able to assign/unassign a phone number for a conferencing bridge, the phone number must be a 'service' number. You can see the type of number it is by navigating to Voice > Phone numbers in the Microsoft Teams admin center and looking in the Number Type column. Microsoft 365 or Office 365 Communications Credits must be set up first in order for users to dial into the bridge on a toll-free number.
Steps when you are assigning a new service phone number to your conference bridge
Step 1 - Assign the new phone number to your audio conferencing bridge
Using the Microsoft Teams admin center
On the left navigation pane, go to Voice > Phone numbers.
Select the phone number from the list, and click Edit.
On the Edit page, under Assigned to, expand the dropdown and then select Conference bridge > Apply.
Step 2 - Change the default phone number of your conference bridge (optional)
The default phone number of your conference bridge defines the caller ID that will be used when an outbound call is placed by a participant or the organizer from within a meeting.
Only a service toll number can be set as the default number for your conferencing bridge; service toll-free numbers can't be set as the default number of your conferencing bridge. If you are assigning a service toll number and you would like to set it as the new default number for your audio conferencing bridge, perform these steps:
Using the Microsoft Teams admin center
On the left navigation pane, go to Meetings > Conference bridges.
Highlight the service toll number that you want to configure as the default.
Select Set as default.
Step 3 - Change the default phone numbers that are included in the meeting invites of users (optional)
The default phone numbers of a user are the ones that are included on their meeting invites when they schedule a meeting. For more information, including how the default phone numbers are assigned for new users, see Set the phone numbers included on invites in Microsoft Teams or Set the phone numbers included on invites in Skype for Business Online.
Using the Microsoft Teams admin center
On the left navigation pane, go to Users and click the Display name of the desired user on the list.
Next to Audio conferencing, click on Edit.
Under Toll number or Toll-free number, select the number from the dropdown and click Apply.
After the changes have been applied, the new default phone numbers will be included on the meeting invites of organizers the next time they schedule a new meeting.
Step 4 - Update existing meeting invites of users using the Meeting Migration Service (optional)
For the next two steps, you will need to start Windows PowerShell.
If you updated the default phone numbers that are included in the meeting invites for some or all of your users, you can optionally update meeting invites that were already sent to users in your organization before their default phone numbers were changed using the Meeting Migration Service. For additional information, see Setting up the Meeting Migration Service (MMS).
- Run the Meeting Migration Service (MMS) for the users who had their default phone numbers changed in Step 2. To do this, run the following command:
- You can also view the meeting migration status. All meetings would be rescheduled once there are no operations in Pending or In-Progress state.
Steps when you are unassigning a service phone number for a conferencing bridge
When you unassign a phone number from a conferencing bridge, users won't be able to join any meetings using that phone number anymore. Because the phone number is changing, it's important to update all users who could have a phone number as their default number (if any) and to update their existing meeting invites before the phone number is unassigned from the audio conferencing bridge.
If the phone number is removed without updating the users and their meetings, their existing meeting invites could contain a phone number that won't work for joining their meetings.
For the first three steps, you will need to start Windows PowerShell. To see how to do this, click Want to know how to manage with Windows PowerShell?
Step 1 - Update users who have the phone number to be unassigned as one of their default numbers
Replace the default toll or toll-free number for all users who have the number to be unassigned as a default number and start the process of rescheduling their meetings. To do this, run the following command:
Set-CsOnlineDialInConferencingUserDefaultNumber -FromNumber <Number to be removed> -ToNumber <Number to be set as new default> -NumberType <"Toll" or "Toll-Free"> -RescheduleMeetings
You can also change the default toll or toll-free number of users in the Microsoft Teams admin center. However, this won't automatically reschedule their meetings.
For additional information, see Set the phone numbers included on invites in Microsoft Teams or Set the phone numbers included on invites in Skype for Business Online.
Depending on the size of your organization, this could take some time to complete.
Step 2 - View meeting migration status using Windows PowerShell
All meetings will be rescheduled once there are no operations in Pending or In-Progress state.
For more information about the Meeting Migration Service, see Setting up the Meeting Migration Service (MMS).
Step 3 - Unassign the old phone number from the audio conferencing bridge
Use the Unregister-CsOnlineDialInConferencingServiceNumber cmdlet to unregister a Toll or Toll free number from a conference bridge
Unregister-CsOnlineDialInConferencingServiceNumber -identity "toll number to be removed" -bridgeId "Conference Bridge ID" Unregister-CsOnlineDialInConferencingServiceNumber -identity "toll free number to be removed" -bridgeId "Conference Bridge ID"
Note: To find the Conference Bridge ID, run the following PowerShell: Get-CsOnlineDialInConferencingBridge.
After a phone number is unassigned from an audio conferencing bridge, the phone number will no longer be available for users to join new or existing meetings.
Save time and automate
To save time by automating this process, you can use the Set-CsOnlineDialInConferencingUser or the Set-CsOnlineDialInConferencingUserDefaultNumber cmdlets.
Use the Set-CsOnlineDialInConferencingUser cmdlet to change the default toll or toll-free number for specific users.
- To change the default toll-free number for a user, run:
Set-CsOnlineDialinConferencingUser -Identity amos.marble@Contoso.com -TollFreeServiceNumber 80045551234
Use the Set-CsOnlineDialInConferencingUserDefaultNumber cmdlet to change the default toll or toll-free number of users based on their original default number or their location.
To find the BridgeID, use the Get-CsOnlineDialInConferencingBridge.
- To set the default toll-free number for all users without one to 8005551234, run:
Set-CsOnlineDialInConferencingUserDefaultNumber -FromNumber $null -ToNumber 8005551234 -NumberType TollFree -BridgeId <Bridge Id>
- To change the default toll-free number of all users that have 8005551234 as their default toll-free number to 8005551239 and automatically reschedule their meetings, run:
Set-CsOnlineDialInConferencingUserDefaultNumber -FromNumber 8005551234 -ToNumber 8005551239 NumberType TollFree -BridgeId <Bridge Id> -RescheduleMeetings
- To set the default toll-free number of all users located in the U.S. to 8005551234 and automatically reschedule their meetings, run:
Set-CsOnlineDialInConferencingUserDefaultNumber -Country US -ToNumber 8005551234 -NumberType TollFree -BridgeId <Bridge Id> -RescheduleMeetings
The location that is used above needs to match the contact information of user(s) that is set in the Microsoft 365 admin center.
Unassign button isn't available
You want to Unassign a number but the button isn't available, and if while hovering over it, you are redirected to contact Support with the following message "Default or shared numbers can´t be unassigned from the bridge. To unassign dedicated toll numbers, please contact support.".
To obtain more information about the bridge(s), run the following Powershell :
Get-CsOnlineDialInConferencingBridge -Name "Conference Bridge"
The result, aside other information like Identity, Name and Region, should also contain the DefaultServiceNumber.
Example, to unassign, the DefaultServiceNumber "8005551234"
Unregister-CsOnlineDialInConferencingServiceNumber -BridgeName "Conference Bridge" -RemoveDefaultServiceNumber 8005551234
About Windows PowerShell
With Windows PowerShell you can manage users and what they are or are not allowed to do. Windows PowerShell can help you manage Microsoft 365 or Office 365 and Skype for Business Online using a single point of administration that can simplify your daily work, especially when you've got multiple tasks to do. To get started with Windows PowerShell, see these topics:
Windows PowerShell has many advantages in speed, simplicity, and productivity over only using the Microsoft 365 admin center such as when you are making setting changes for many users at one time. Learn about these advantages in the following topics: