From the customer view in https://admin.webex.com, go to Calling > Locations.


Select the location where you would like to change the main number.


Under Main Number, choose the phone number from the drop-down menu.


For extension-only users, this is the caller ID number. For PSTN calls, this number can be assigned to users or features.


If you choose a toll-free number as the main number for a location, we recommend updating the Emergency Callback Number for the location because a toll-free number does not have an emergency services address. For more information, see Configure Emergency Callback Number for a Location.


Click Save.