Q. I've got 10 credit cards and don't use but four or five of them. Is it wise to keep the unused cards around? I've heard credit-rating agencies give lower scores to people with too many cards.

A. In general people who manage their finances responsibly can keep credit-card accounts gathering dust without much worry, credit experts say.

The number of credit cards is a minor factor in credit scoring. Keeping the account open probably works more in your favor than against it if you have good credit, according to MyFICO.com, the consumer arm of the company that developed formulas used by credit reporting agencies.

"If your pay history is good and you're not maxed out on everything, you're doing fine," said Barry Paperno, manager of consumer operations for Fair Isaac Corp., operator of MyFico.com.

There are several reasons for this, he said. For one, a credit report will include all credit cards, including those accounts that have been closed or not used for years, he said. Typically a credit card will remain on the report for a decade after its last use.

"While there's nothing you can do about that, it's not going to affect you very much," Paperno said.

Moreover, keeping a card could help you if you are applying for a mortgage or car loan. Lenders look at how much you owe compared with your total available credit.

If someone has a $1,000 balance on cards with a total of $10,000 credit available, they are using 10 percent of their credit availability. If the person closes one of the cards with $5,000 of credit available, they now are using 20 percent of their available credit.

"You could do more damage by closing them," said Wendy Burkholder, executive director of Consumer Credit Counseling Service of Hawai'i. "It can appear you're using every dime available to you and that's not a wise choice."

Credit scoring is broken into five areas, of which payment history and outstanding debt account for 35 percent and 30 percent of the report. A big part of outstanding debt is the ratio of credit-card balances to available credit, Paperno said.

The number of cards one has fits into a category only accounting for 10 percent of the scoring. Another 10 percent is devoted to new credit, which includes credit inquiries and new accounts opened.

Credit history accounts for 15 percent. Burkholder said lenders see value in someone who's got a long track record with credit. Canceling a credit card would keep you from building a longer history that's attractive to lenders reviewing your credit reports, she said.

Paperno said the best solution for someone with unused credit cards may be to keep the accounts open but take a scissors to cards. He said that would cut down on unauthorized use of cards or ID theft.

"Any card you're not using I would cut them up and throw them away," Paperno said. "But in terms of leaving an account open or requesting the card issuer close it, for scoring purposes I would recommend leaving it open."

Burkholder, who advises consumers with debt problems, said her average client has eight credit cards with a balance totaling $18,000. She said credit card debt is a major factor for consumers experiencing financial woes.

That compares to the average U.S. consumer who has seven cards, according to MyFico.com. About half of card holders carry a balance of less than $1,000. Generally people should avoid carrying balances that are 50 percent of available credit. Maintaining low balances is one way to get a good credit score, Paperno said.

Have a question about money matters? Send it to Akamai Money columnist Greg Wiles at gwiles@honoluluadvertiser.com or call 525-8088.

Reach Greg Wiles at gwiles@honoluluadvertiser.com.