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Blocking your telephone number from being displayed

You can block your telephone number from being displayed when you make a call. That way, the person you are calling does not see your number in the display of their telephone. This function is called "caller ID blocking" or "CLIR" (Calling Line Identification Restriction). You can either block your telephone number (caller ID) for just a specific call or for all of the calls you make.


  • The FRITZ!Fon must be registered with a FRITZ!Box.
  • The feature "caller ID blocking (CLIR) for individual calls" must have been enabled by your telephony provider.

1 Blocking caller ID for a specific call

You can block your caller ID for just one call. After that call, your caller ID will be displayed every time you make a call:

  1. Press the "Menu" key on the telephone.
  2. Scroll to "Settings" and press "OK".
  3. "Telephony" > "OK" > "Anonymous call" > "OK"
  4. Enable the option "Next call".
  5. Press the "end call" key.

2 Permanently blocking your caller ID (for all calls)

  1. Click "Telephony" in the FRITZ!Box user interface.
  2. Click "Telephony Devices" in the "Telephony" menu.
  3. Click the (Edit) button for the respective telephone.
  4. Click on the "Telephony Device Features" tab.
  5. Enable the option "Calling line identification restriction (CLIR)".
  6. Click "Apply" to save the settings.