A credit freeze prevents lenders from pulling, viewing and thus modifying your credit reports. No one, including yourself, should be able to open any type of credit in your name while a freeze is active. For these reasons, initiating a credit freeze has become a popular tool among consumers who are dealing with the aftershocks of identity theft.
In fact, most states used to only allow victims of identity theft to initiate a credit freeze. However, the major Credit Reporting Agencies recently modified their policies and now allow anyone to lock their reports. Be aware that you may have to pay a small fee if you haven't been a victim of identity theft, but the rest of the process basically remains the same.
It begins by making separate contact with each of the credit reporting agencies—Equifax, Experian and TransUnion. As each bureau has a different process for activating a freeze depending upon your state, you'll want to check their websites first to determine the best way for you to apply and provide the necessary documentation. Equifax, for example, allows you to submit your personal information online to start the process, but also requests that other supporting documentation (e.g. police reports) be sent separately by mail.
Once your application is approved and the credit freeze is initiated, you'll also receive a special PIN which you'll need in order to unlock your credit reports in the future. Be sure to store your PIN in a safe place. If you misplace it and need to unlock your credit on short notice, jumping through the security hoops and attempting to get a new PIN issued may very well take more time than you have.