If you're like most people, you probably assumed that age, driving record, and experience behind the wheel were the main factors in determining your insurance premiums.

Silly you.

Turns out that your spendthrift ways may have an impact on what you pay to insure your car and home, even if you're a long-standing customer and generally an upstanding citizen.

Telling signs in your credit report
More and more home and auto insurers rely on credit data as a predictor of future loss, using it to decide whether they will accept, cancel, or renew home and auto policies, and exactly what they'll charge you for them.

What's the credit-auto claims connection? Industry studies show that certain financial strikes -- such as payment delinquencies, outstanding credit card balances, collections, foreclosures, and bankruptcies -- are linked to the likelihood that a person will file a claim. But even pristine customers are being hit with higher rates. Those who have "no hits" on their credit record -- because they use cash, not plastic, for purchases -- get squeezed because in the eyes of the industry, they have no credit history.

The majority of insurance companies use an insurance-specific risk scoring system to determine whether to do business with you, and at what rate. Many use that data in tandem with credit report information to set rates. However, some states do not allow insurers to use the credit to make business decisions at all. (To find out whether your credit is used to calculate your rates, call your insurance company and directly ask.)

Are you ready to let your credit speak for your driving acumen? Now you have another reason to clean up your credit. Pull your credit reports from the three major agencies -- Equifax (NYSE:EFX), Experian, and TransUnion -- at annualcreditreport.com and review them closely for accuracy.

Make any needed repairs so there are no surprises come home or auto insurance policy renewal time.

More Motley Fool tips on cleaning up your credit:

Dayana Yochim keeps her insurance premiums down by driving a beater car and keeping it parked in one spot most of the time. She doesn't own shares of the companies mentioned in this article. The Fool has a disclosure policy.