Generally your phone number is put on view automatically on the display of the person you are calling. If you activate the Calling Line Identification Restriction Service (CLIR), your number will be "concealed" for the opposite number.
How does it work
When you have CLIR activated and you wish to show your phone number, add *31# each time before the number you dial.
For example: if you dial *31# 089 XXXX XXX only for this call, your number will be put on view at the display of the dialed phone.
How much does it cost
Activation, deactivation, access and use of this service are free of charge.
How do I get the service
Calling Line Identification Restriction Service (CLIR) can be requested through the Customer Care Service on 123.
The service is available for post-paid subscribers only.