Following news that a credit-check subsidiary of the credit bureau Experian had been breached and that detailed information — including Social Security Numbers and birth dates — of 15 million T-Mobile customers and applicants had been included in the files breached, we issued a statement and also joined several leading groups in a letter (attached below) to the two firms. In the letter, we criticized the firms for offering credit monitoring, instead of free credit freezes, to victims, since only a credit freeze stops new account identity theft. When a thief obtains both a Social Security Number and a birth date, face a very real risk of new account identity theft. The credit or security freeze, available nationwide, is your best defense, because it prevents new creditors from accessing your credit report. Most creditors will not issue credit without looking at a credit report. Credit monitoring, on the other hand, only tells you after theft may have already occurred. Our security freeze tips explain the difference.