How Much Does Your Available Balance Affect Credit Scores?

The amount of debt you carry determines 30 percent of your credit score, according to Fair Isaac Corp., or FICO. It's not just a matter of how big a balance you carry but how much available credit you have left on your credit cards. The exact effect varies: If you're barely above water, maxing out your cards will hurt you more than if your debt is under control.

Debt Utilization

If you have a $5,000 limit on your card and you carry a $1,000 balance, your debt utilization ratio is 20 percent; if you carry $4,500 on the card, it's 90 percent. Lower is definitely better. Your credit score takes into account how big the balance is on each card and how large the total utilization is for all your accounts. If you have two or three maxed-out cards and a couple with nothing on them, the untapped cards may improve your score.

Contributing Factors

Debt utilization doesn't determine 30 percent of your score by itself. The actual dollar amount you carry plays a role, and the number of accounts that carry balances. If you have installment loans, such as a mortgage or a car loan, the amount you've paid off is a factor. The scoring system that juggles all these elements is secret, so it's impossible to predict the effect of one element on your overall score.

The Good Ratio

If you'd like to know the ideal level of debt utilization for an optimum credit score, you have plenty of recommendations, but they're not consistent. Financial advisers have proposed everything from 50 percent down to 10 percent. FICO recommends you keep the ratio on every card no higher than 10 percent: This should benefit your score, subject to all the other factors. Top-flight borrowers have scores of 7 percent or less.

Improving

If you haven't thought about the balance limit on your cards in a while, look at them now. Work out your ratio, both overall and on individual accounts. Paying down the balances on the highest-ratio cards goes a long way to improving your score, as well as saving on monthly interest. Taking out new cards to improve your ratio is a mistake. Adding several new credit accounts hurts your score. Lenders may also worry the added credit is a sign you're about go on a spending binge.

About the Author

Author of two film reference books, "Cyborgs, Santa Claus and Satan" and "The Wizard of Oz Catalog." Published in Air & Space, Backpacker, Newsweek, The Writer, and multiple trade journals (can fax samples if requested, don't have them available digitally)