Credit Score to Ignore Authorized User History

the formula for the widely used FICO credit score is about to change. Fair Isaac Corp., creator of the FICO score used by lenders, says it will no longer consider authorized user accounts when factoring a consumer’s score. An authorized user of a credit card is free to use the plastic, but doesn’t have to pay the bill. Parents often make a child an authorized user of their card to give a youngster access to credit. But this has other perks. The child inherits the parents’ credit history. And if it’s a good one, the child receives a high credit score.

But some Internet-based credit-repair firms have been using this to boost the credit scores of strangers with poor credit. The firms pay a person with an excellent credit score to add someone with a rocky record as an authorized user on a card for a few months. The authorized user doesn’t ever use the plastic. Instead, he or she gets the benefit of the account owner’s credit history, which can raise a weak score by a couple of hundred points.
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Worse for some, the change will mean no FICO score at all. Fair Isaac estimates 1.5 million to 3 million consumers will no longer have enough information in their credit report to be able to produce a FICO score. Among those most likely affected are young adults who have been added to their parents’ accounts.