Doug Heller, director of insurance with the Consumer Federation of America, said many good drivers are being penalized with rates based on factors that have little to do with their driving. In most states, you may pay higher premiums if you have poor to fair credit, even if you have a pristine driving record. Insurers use a variation of consumer credit scores — similar to the ones lenders use to determine the risk of a borrower repaying debt — as one of several factors to assess a driver’s likelihood of filing an insurance claim.

A recent report by the Consumer Federation of America about insurance premiums in New York found that drivers with perfect driving records and excellent credit pay an average of $730 a year for basic insurance, while drivers with the same driving record but poor credit average almost $2,100. The federation supports eliminating the use of credit scoring in insurance rating, saying it especially harms lower-income customers and people who live in minority neighborhoods. (At least three states — California, Hawaii and Massachusetts — bar the use of credit scoring in setting these premiums, and a few others limit its use.)

Insurers defend giving better rates to drivers with good credit, saying it makes sense because those customers are less likely to file insurance claims. “The vast majority of customers get a better rate because we’re using credit scoring,” Mr. Passmore said.

Car insurance is hard to avoid because basic coverage is mandatory in most states. So what can you do to lower your bill? Chuck Bell, programs director of advocacy at Consumer Reports, recommends seeking out three or four quotes from different insurers to see if they can offer lower rates. Many consumers remain with the same insurer for decades, he said, but it’s smart to check prices from time to time. “We think you should shop annually,” he said.

While many people “would rather get a root canal,” he said, getting auto insurance quotes isn’t difficult. He suggests calling insurers on the phone, but you can also get quotes directly on insurer websites. (Sites that aggregate information can give you a general idea, he said. But for specific quotes, it’s best to deal directly with insurers or independent agents that represent multiple carriers.) Have your current policy handy so you can easily compare coverage.