You may not know it, but you have a personal "credit score." Your score indicates how likely you are to pay your bills on time. Lenders use it to help decide whether to give you a loan and, if so, at what interest rate.

The facts about you come from credit reports compiled by the three leading credit bureaus, Equifax, Experian and Trans Union.

If your credit habits resemble those of people who pay their bills on time, you'll score high. Otherwise, you'll score low. Lower scorers have to pay higher interest rates and may not get any credit at all. Borrowers with high credit scores pay lower rates.

The most widely used scoring systems are constructed by Fair, Isaac, in San Rafael, Calif.

You can obtain your credit score for a fee from a few different sources.

Once you've checked your score, what next?

You don't have to do a thing if your credit falls into the range that lenders deem "excellent." The report may tell you how to raise your score by a few more points, but that wouldn't make any difference to your life. You're already being offered credit on the very best terms.

Credit scores generally range from 300 to 850. Every lender has different cutoff points, for what's acceptable. Here's a general guide, from E-Loan:

Excellent scores above 730. Good 700-729. Needs a closer look 670-699. Higher risk 585-699. No credit or limited credit below 585.

If your record is "good" or toward the upper end of the "closer-look" range, look for ways to improve it. The best and fastest ways are to pay any delinquent bills and lower your total credit-card debt.

Start at the top

Debt reduction should start with the cards where you're closest to your credit limit. And make sure to make all future payments on time.

Some of the other quick fixes that people try usually don't work, says Tom Quinn, Fair, Isaac's director of consumer initiatives. For example:

Closing unused credit cards probably won't raise your score. The models look at how you use the credit you've got, rather than the amount you have available. Individual lenders, however, might feel more comfortable if you reduced the amount of open credit you have available.

Paying off one delinquent bill won't raise your score by very much if your record is littered with other credit blemishes. Credit scores consider patterns of behavior. You have to show yourself creditworthy over a period of time.

Making all your minimum payments won't make you look good if your cards are maxed out or anywhere close to it. Credit scores look at how much of your available credit you've used. When you're close to the line you look out of control.

Opening new, debt-free cards won't make you look better, if your other cards are maxed out. True, your average debt looks lower compared with your total, available credit. But new credit lines don't weigh as heavily in the formula as old ones do.

You lose points if you never use your credit cards. Lenders want to see that you can charge purchases and repay on time.

Some balances help

You don't improve your score by carrying balances forward from month to month, as opposed to paying each bill in full, Quinn said. But lenders may mail more offers to people who carry balances, because they pay interest on their accounts.

If you're comparison-shopping for a mortgage or auto loan, make all your inquiries within a 14-day period. Those will be grouped together and counted as a single inquiry. Spread-out inquiries register separately and make it look as if you're hungry for credit. That knocks down your score.

Here's a tip for mortgage shoppers with middling scores: Apply for a loan at a conventional bank, just as people with good scores do.

Some of you go to "subprime" banks that specialize in mortgages for people with poorer credit. But those loans are expensive.

According to the Federal Home Loan Mortgage Corp., as many as one-third of the borrowers at subprime banks may qualify for lower rates at conventional banks. That might mean you.

Syndicated columnist Jane Bryant Quinn can be reached in care of the Washington Post Writers Group, 1150 15th St., Washington D.C. 20071-9200.

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