Prepaid Phone Card Blog: Phone Card Depot: Are Calling Cards Anonymous?

Phonecarddepot.com ran a simple test to see if your anonymity is protected when using a prepaid phone card. The test: does the number you are calling from show up on the call display of the phone you are calling?

The way calling cards work is that your local access number connects you to a server that routes your call through the carrier's lines or through the Internet to a gateway in the call desination city. Phone Card Depot's hypothesis was that the call display on the receiving phone would display either the local access number that we dialed or a number associated with the destination gateway, not the real number that we made the call from. Our staff was surprised at the results.

Our GM, Tavis McKenzie dialed his Motorola i830 cellular phone from the Phone Card Depot office landline and took pictures of the call display.

Phone Card Depot's landline number is 905-737-6478, let's see what shows up in the call display of his Motorola i830 cellular phone.

Using CiCi Calling Card
Number Calling From: 905.737.6478
Number on Call Display: 905.737.6478 (correct)
Result: Not Anonymous

Using Telus Calling Card
Number Caling From: 905.737.6478
Number on Call Display: 780.402.0002 (incorrect)
Result: Anonymous

From these results it was concluded that the type of calling card used is what was important to anonymity. Today's calling cards are routed through two different systems: VOIP and traditional land lines. Upon further research we believe that cards running off of VOIP systems are usually not anonymous because they pass the number you are calling from through to the destination telephone's call display. Calling cards that are run off of the traditional call-routing schema are considered anonymous.