FICO- Amounts Owed

Keep balances low on credit cards and other “revolving credit”.
High outstanding debt can affect a credit score.

Pay off debt rather than moving it around.
The most effective way to improve your credit score in this area is by paying down your revolving credit. In fact, owing the same amount but having fewer open accounts may lower your score.

Don’t close unused credit cards as a short-term strategy to raise your score.

Don’t open a number of new credit cards that you don’t need, just to increase your available credit.
This approach could backfire and actually lower your credit score.

*www.myfico.com