What Does It Mean When a Call Comes Up Unknown Caller?

By Sue Smith

Caller ID helps you to decide whether to answer a call.
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Most telephones now have display screens on which you can see information about incoming calls. The Caller ID system makes this possible. In most cases, you should see accurate information about who is placing an incoming call, including a telephone number and optionally a name. In some cases, you will see "Unknown" instead. There are potential risks associated with unknown calls. How these situations are handled depends on your phone handset, your service provider and some options you can control.

Caller ID

Depending on the company providing your telephone service, you may have to enable Caller ID and in some cases pay for this service. If your phone never displays Caller ID information, contact your service provider to find out about enabling the service. If your phone does not have a display feature, the Caller ID information cannot be shown.


The Federal Communications Commission rules provide the ability for callers to block the Caller ID information when making calls, preventing it from being displayed on receiving handsets. The FCC rules require telephone companies to make the ability to block Caller ID information available to telephone users at no charge. You can opt to block the information for all outgoing calls or just for individual calls by pressing *67 before making a call. If you receive a call from an unknown caller, the caller may have taken this step before making his call. The telephone companies provide the ability for callers to hide their names as well as their numbers.


If a caller has Caller ID blocking enabled for a phone line, he can opt to allow the ID information for particular calls, by pressing *82 before making a call. If a caller comes up as unknown on your phone, he has not taken this step. The ability to make anonymous calls is provided by law, as is providing accurate Caller ID information. For example, the practice of Caller ID spoofing, whereby a caller fakes information to make it look as though a call is coming from another number, is prohibited by the 2009 Truth in Caller ID Act.


In some cases, a caller may have a legitimate reason for hiding his identity. However, there can also be sinister reasons for concealing this information. If you receive a call from an unknown caller, you need to be aware that he may not be who he claims to be and therefore you should be careful with any information you give him. Telephone companies are able to provide the option to block any calls from unknown callers if you would prefer not to receive these calls at all.