Back in June FICO announced they would be rolling out a new formula for calculating their credit score used by all three major reporting services. This updated product would no longer consider an authorized user account as a valid card holder and any credit information about the authorized user would be dropped. This seemingly minor change is expected to affect over 30 million US cardholders, inducing a small to moderate drop in their credit scores.

Now Capital One has announced they will start, for the first time, reporting the credit limits of their card holder accounts. But how does this affect you?

This recent policy change by Capital One may alter the credit scores of some cardholders. Since FICO bases around 30% of their score on credit-to-debt ratio, having accurate credit limit data available will make their scoring product more accurate. The real impact though will be mostly unknown until the changes are made and have had a chance to work through the FICO system and roll out to the credit reporting agencies.

Currently only Capital One and American Express withhold credit limit information when reporting account data to FICO. The effect of these policies is widely disputed. Some argue that not having the credit limit amount available causes FICO to arbitrarily assign the outstanding balance as the credit limit. This would cause all AMEX and Capital One account holders to appear as though there cards were always "Maxed Out" or at their limits, a condition likely to severely harm one's credit score. They also believe that when Capital One starts reporting the credit limits, their account holders will enjoy a miraculous increase in their FICO score and consequential reduction in interest charges.

This writer believes otherwise.

Fair Isaac Corporation (FICO) has been in the business of evaluating consumer credit-worthiness for over 50 years and employs nearly 3000 people. FICO credit information is used by 99 of the top 100 US banks to base the decisions of billions of dollars each year. The method for determining a FICO score is not a clear cut, simple formula. It is a large, dynamic algorithm that FICO stakes their reputation and future on. It is also adaptive, predictive and a closely guarded trade secret. I, personally, am convinced that FICO handles Capital One and American Express data correctly and estimates an accurate credit limit. This is further substantiated by the fact that American Express customers do not suffer undue harm by the AMEX policy of not reporting limits. In fact, having an AMEX card can be a major boost to your credit score.

Let's look at just one small example of how a credit limit can be estimated. Suppose four months ago you used your Capital One card to purchase a new 60? plasma TV for $3000 dollars. FICO would see this transaction and apply a credit limit of at least $3000 to your account. The actual limit would probably be some percentage higher based on the likelihood that you did not max the card out. This limit would remain on the account, maybe fluctuating with your general credit score and current financial situation. Do not forget that FICO has access to a very large amount of data over a very long period of time.

When the smoke clears from this latest reporting change, the scores of most Capital One customers will likely remain about the same. Some will go up a little and some will drop slightly. Perhaps a more interesting discovery will be to see just how well FICO has been doing in estimating the credit limits of these two companies account holders.