How come my phone number is not working

Withhold number: How to call anonymously with your mobile phone

The subject of data protection is an important issue in times of GDPR and the World Wide Web: This applies to name, address and of course to your own mobile phone number. Here in the article you will find out how you can suppress your own phone number - regardless of which smartphone you are using.

Table of Contents

Withhold number - this is possible

In principle there are three different options: The mobile phone number unique withhold the number for a call permanent suppress for all outgoing calls or selected contacts Call permanently suppressed.


Withhold number on Apple iPhone

The phone number is suppressed on the iPhone via Settings> Phone Caller ID

If you want to permanently suppress the transmission of your own number for outgoing calls, proceed as follows:

  1. Settings
  2. phone
  3. Send my caller ID

Alternatively, you can permanently suppress the phone number by entering a GSM code, so you don't have to struggle through the settings. To do this, press the key combination in the dialing field *31# and then press Call. To deactivate permanent number withholding, select #31#.


Calling number suppression on Android smartphones

In the settings of the Android smartphone (here a Huawei P30) the number is suppressed in this menu

Like all iPhones, all Android phones are equipped with a function that allows you to suppress your own number. Depending on the Android version, the exact path to the setting can differ slightly - but basically everything is very similar. Using the Huawei P30 Lite as an example, we proceed as follows:

  1. Go to "Settings" in the menu
  2. "Cellular network" menu item
  3. "Call settings" sub-item
  4. For dual SIM devices, click on "More" for the respective SIM
  5. Under “Caller ID” you can choose whether the number should be withheld or not

You can also get to this point directly in the telephone menu of your mobile phone, click on the three points one below the other, select “Settings”, now the “More” point and select in the “Caller ID” menu field whether the number should be transmitted.


Withhold number for call once

If you want to withhold your own phone number once, you can type in this code before entering the number

If you only want to suppress the call number for calls to a specific number, proceed as follows:

  1. Open the selection field of the mobile phone
  2. Enter the key combination # 31 #
  3. Then append the desired number
  4. Press "Call" - the relevant contact will be called with the number suppressed


Withhold the number for selected contacts

If you only want to anonymously contact selected contacts in your phone book, the principle is actually similar to that described above. All you have to do is prefix the stored telephone number with the code # 31 #. It does not matter whether the number is saved in the format # 31 # 0172… or as # 31 # + 49172…, for example.


Can the withheld number still be traced?

Yes, the withheld number can be traced. It is suppressed for the called party, but authorities or network operators are able to find out anonymous calls. Otherwise criminals would have had an easy time of it.


Suppress phone number in Whatsapp group chats

By using group chats in WhatsApp, it is quite possible that people from your environment come into possession of your mobile phone number without you perhaps wanting to do so yourself. Those people can then save your number and send you a message privately or call you.

You cannot hide or hide your own number in Whatsapp group chats at the moment (as of March 2020). But there are other options here too. In the alternative messenger service Telegram, however, it is possible to replace your own number with a user name. If you add a person from a group chat to Telegram via the user name, the mobile phone number is not visible - unless the unknown person has already saved you as a contact in the mobile phone.


Other helpful GSM codes in addition to number suppression

There are a number of other useful GSM codes for your smartphone. GSM stands for Global System for Mobile Communication and is, so to speak, generally applicable to the subject of cell phones and not dependent on the provider. The codes therefore work regardless of whether you are a Telekom, Vodafone or o2 user:

Activate call diversion** 21 * destination number #
Deactivate call diversion##21#
Activate call waiting*43#
Deactivate call waiting#43#
Show IMEI (serial number)*#06*
change PIN** 04 * old PIN * new PIN * new PIN #