6 ways to kill your credit score

Lenders, insurers, landlords and others will charge you more or flat-out reject you if you show up with a low FICO score. Here's how you may be doing yourself harm.

How your score affects your mortgage rate
For a $300,000 30-year fixed-rate loan
FICO score APR Monthly payment
760-850 5.860% $1,772
700-759 6.082% $1,814
660-699 6.366% $1,870
620-659 7.176% $2,031
580-619 8.820% $2,375
500-579 9.679% $2,562
Source: myFICO.com; rates as of May 7, 2007
Be a payment-slacker
Sending in your loan or credit card payments late can really hurt.

Rex Johnson, founder of credit union consulting firm Lending Solutions Consulting, estimates that when you're 30 days past due and your balance is still unpaid, your score could take a 60-point hit. That kind of drop could mean a much higher interest rate on loans you take out (see table at right).

Late payments from your past that you have since paid off will have less and less of a negative effect on your score as time goes on. Johnson estimates that on average past delinquencies that have since been resolved might cost you 15 to 20 points.

To boost your score: Pay your bill in full and mail it as soon as it arrives, or at the very least the minimum due. Set up automatic online bill payments so you'll never be late. Or, if you are late one month, be sure to pay off what you owe as soon as possible.

Be a bad-timing big spender

Be a slacker

Be too thin

Be too young and eager

Be too tidy

Be too nonchalant
Saving and spending aren't the only factors affecting your net worth. How you manage (or don't manage) your assets and liabilities can make a big difference, too. (more)
You don't have to spend a lot of time to put your financial house in order. (more)