How to Find My PIN Number
The PIN number on a BlackBerry cellphone is an eight-digit alphanumeric number that identifies the BlackBerry handheld to the BlackBerry network. Each BlackBerry has a unique PIN. Once you have your BlackBerry's PIN, you can use it to send PIN to PIN messages to other BlackBerry users. PIN to PIN messages are similar to text messages, but your cellular provider doesn't charge extra or count them against your text messaging limit. There are four ways to find a BlackBerry's PIN number.
Locate the BlackBerry's PIN through the menus by selecting "Options" and selecting "Status." The PIN is under the field labeled PIN.
Locate the PIN on the BlackBerry Desktop Manager when the BlackBerry is connected to a Windows computer. Open the Desktop Manager by clicking on the BlackBerry icon by the clock. The PIN number appears in the bottom-left corner of the window.
Look for the PIN on the BlackBerry's box. It is on a sticker on the side or bottom of the box, along with various other information about the phone.
Find the PIN on the back of the phone underneath the battery. To remove the battery on your BlackBerry, slide off the battery cover by pressing down on it with your thumb and pulling it toward the bottom of the phone. Pinch the edges of the battery with your fingers, and pull it out. The PIN is printed on a sticker on the back of the phone.