FRITZ!Box 7581 Service - Knowledge Base
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.
Note:The configuration procedure and notes on functions given in this guide refer to the latest FRITZ!OS for your FRITZ!Box.
1 Enabling CLIR on a case-by-case basis (only 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:
Configuring a telephone to use the keypad function
The following steps are only necessary if the cordless telephone is not registered with the FRITZ!Box's base station:
Note:If you are using a telephone that is registered with the base station of your FRITZ!Box (for example FRITZ!Fon C5), you do not have to configure it to use the keypad function.
- Configure the devices so that you can dial special characters (such as * and #) or send keypad sequences (sequences of symbols and digits, such as *121#) with them.
Note:Many Gigaset telephones can be configured as follows: Select "Operation at a PBX" from the telephone's menu, then select "Dialing options" and enable the option "Dial * and #".
Suppressing your telephone number for the next call
- When making a telephone call, dial the prefix *31# before the number you wish to call. Your caller ID will then be suppressed for this call.
In order to suppress your number when calling the telephone number 0301234, dial *31#0301234.
2 Permanently suppressing your caller ID (for all calls)
You can also permanently suppress your caller ID for all calls. To do so, you must enable CLIR (Calling Line Identification Restriction) in the FRITZ!Box or your telephone. The procedure depends on the type of telephone you are using:
Note:If you have enabled permanent suppression of the caller ID, you can still transmit your caller ID for one call. To do so, simply dial the prefix #31# before the actual number, for example #31#0301234. Your caller ID will now be transmitted only for this call and suppressed for the following calls.
Enabling CLIR for analog and cordless telephones
- Click "Telephony" in the FRITZ!Box user interface.
- Click "Telephony Devices" in the "Telephony" menu.
- Click the button (Edit) for the relevant telephone.
- Click on the "Telephony Device Features" tab.
- Enable the option "Calling line identification restriction (CLIR)".
- Click "OK" to save the settings.
Enabling CLIR for IP telephones
- Enable the CLIR function directly on the IP telephone. You can find information on configuring the device in its manual, or consult its manufacturer directly.
Note:You can enable CLIR in FRITZ!App Fon by tapping "More > Settings > CLIR on".