You can change your caller ID on any extension to display any local or mobile number associate with your account. You cannot change it to a 13, 1300 or 1800 number as they are inbound only services in Australia, making it illegal to use them for outbound calls.
How to Change Your Caller ID
Step 1 - Under the Phone System menu, select Phone Users.
Step 2 - On the Phone Users page, click Edit next to the user you wish to modify.
Step 4 - Select the drop down next to Caller ID this will display all the available Caller ID's.
Note - Any local or mobile number attached to your account can be used as the Caller ID. 13/1300/1800 are inbound only services in Australia, making it illegal to use them for outbound calls.
Selecting a number that is marked as AVAILABLE will set this number up as a new service, and create a direct callflow for this number to direct calls to the user you are editing.
Step 6 - Once you have selected the Caller ID select save.
Note - Changes will take up to 15 minutes to take effect.
How to Hide Your Caller ID
Alternatively to hide your caller ID tick the checkbox next to Hide Caller ID. This will make all calls from this extension be displayed as a private number.