FRITZ!App Fon Service - Knowledge Base

FRITZ!App Fon Service

Suppressing your telephone number

You can suppress your telephone number when making calls so that it is not transmitted to the party you are calling. That way the party you are calling does not see your number in the display of their telephone. This function is called "CLIR" (Calling Line Identification Restriction). You can either suppress your caller ID for a single call or permanently suppress it for all calls.


  • Your telephony provider must have enabled Calling Line Identification Restriction (CLIR) on a call-by-call basis for your telephone line.

1 Suppressing the number on a case-by-case basis (for a single call)

You can suppress your caller ID for a single call. Your caller ID will be transmitted again when you make subsequent calls:

  1. When making a telephone call, enter the prefix *31# before the number you want to call. Your caller ID will then be suppressed for this call.

    To suppress your number when calling the telephone number 0301234, enter *31#0301234.

2 Permanently suppressing your caller ID (for all calls)

  1. Start FRITZ!App Fon.
  2. Tap "More" and then "Settings".
  3. Enable the option "Tel. No. Suppressed".