Caller ID Spoofing is the practice of displaying a user defined phone number on a recipient’s caller ID, rather than that of the originating station. This effectively allows the user to display a number of their choosing, instead of their own. Just as email spoofing can make a message appear as if it originates from any email address a sender chooses, caller ID spoofing can make a call appear to have come from any phone number the caller chooses.

There are several ways to spoof a caller ID, but the easiest way is to use a PIN based service. These services allow non-technical users to use a calling card with pre-paid minutes to place their calls, and change the originating phone number with ease.

The process is very simple. To begin, the caller will dial in to a number provided to them by the company and enter their PIN. Next, they will dial the number that they wish to call, followed by the number that they wish to appear on the caller ID. Typically, a number of options are then presented (voice changing, recording, etc.). Once the customer selects their desired options, their call is connected.

In addition to the calling card service, many providers are now offering a web-based interface in which customers can place calls from. Using a web-based spoofing service is also very easy. The user must create an account, log-in, and fill out a simple form. Most companies require the following: source number, destination number, and caller ID number.