It is called a hidden call or call with a hidden number when the number of the phone that makes the call is not displayed on the phone that receives the call. There are cases in which it cannot be done, these are in calls made to emergency services such as police or firefighters. Today we inform you how to call with a hidden or private number. There are different reasons why you need or want to remain anonymous in any or all of the calls you make. These can be playing a joke on a family member or friend, carrying out some kind of survey anonymously or also if you are a company and you do not want to be called back. On many occasions, you only seek to sow doubt in the person you are calling, which will cause the other person to try to find out who is calling with a hidden number. Mobile and landline phones work by default with identification on all outgoing and incoming calls that are made. However, there are ways to change this feature. Call with the Private Number If your objective is to keep your identity hidden indefinitely, you should only contact the Customer Service Department of the company that provides your service. Currently, this service has no cost and from the moment you request the activation of this service, all your calls will be made concealing your identity. You will always have the option from your mobile, to decide which calls you to show your phone number. To show your number in a specific call from your mobile, you just have to put the following digits before the phone number to call: # 31 # Example: If the call will be made to 666777888, you must dial: * 31 # 666777888. Immediately you end the call, the concealment of the ID will be activated automatically and all the others will remain private. In the case of calls you make from the landline, it applies in the same way as long as you have asked your company that all calls be private, you just have to change the combination * 31 # to * 67 #. Activate the Private Number for Mobile Calls