How Insurers Calculate Your Rate

Car insurance isn't priced on a single number — it's the result of many variables assessed together. Insurers use a process called underwriting to evaluate how likely you are to file a claim, and they set your premium based on that estimated risk. Understanding which factors carry the most weight can help you make sense of your bill and identify where you might have room to save.

For a deeper look at how the different parts of a policy fit together, see our breakdown of what auto insurance actually covers.

The person behind the wheel matters as much as the vehicle itself. Insurers typically weigh the following:

  • Age and experience: Younger drivers — particularly those under 25 — tend to pay higher rates because statistical claims data shows higher accident rates in that group. Rates often drop as drivers gain experience and maintain a clean record.
  • Driving history: At-fault accidents, moving violations, and DUI convictions raise your perceived risk and can increase your premium significantly, sometimes for three to five years after the incident.
  • Credit-based insurance score: In most U.S. states, insurers use a version of your credit history to help predict claim likelihood. A lower score can result in higher premiums. A few states — including California, Hawaii, and Massachusetts — restrict or prohibit this practice.
  • Annual mileage: The more you drive, the more exposure you have to potential accidents. Drivers who commute long distances typically pay more than those who drive infrequently.

Credit Scoring Rules Vary by State

While most U.S. states allow insurers to use credit-based insurance scores in rate calculations, several states have laws limiting or banning the practice. If you live in one of those states, your credit history won't factor into your auto insurance premium at all. Check your state's insurance commissioner website for current rules in your area.

Common misconceptions about these factors are worth examining. Our article on auto insurance myths addresses several that can lead to poor decisions.

Vehicle and Location Factors

What you drive and where you park it also affect your rate considerably.

Premium

The amount you pay — monthly, semi-annually, or annually — to keep your insurance policy active. It is not the same as your deductible.

Underwriting

The process insurers use to evaluate risk and decide what to charge a given driver. It involves reviewing personal, vehicle, and location data.

Deductible

The amount you agree to pay out of pocket before your insurer covers the remainder of a covered claim. A $500 deductible means you pay the first $500.

Credit-based insurance score

A score derived from credit history data that many insurers use — where state law allows — as one predictor of future claim activity. It is distinct from a traditional credit score.

At-fault accident

A collision where your insurer determines you were primarily responsible. At-fault accidents can raise your premium at renewal and may stay on your record for several years.

  • Vehicle make, model, and year: Insurers consider a car's repair costs, safety ratings, theft rates, and how it performs in crash tests. A vehicle with expensive parts or a high theft rate typically costs more to insure.
  • Location: Urban areas with heavy traffic, higher crime, or more frequent severe weather events generally carry higher premiums than rural areas. Even moving across town can shift your rate.
  • Garage vs. street parking: A vehicle stored in a private garage overnight is considered less exposed to theft and weather damage than one parked on the street.
  • Coverage choices and deductibles: The coverage types you select — and the deductible amounts you agree to — directly shape your premium. Choosing a higher deductible lowers your monthly cost but means you pay more out of pocket when you file a claim.

Insurance is one piece of a larger financial picture. Our article on the true cost of car ownership puts it in context alongside fuel, maintenance, and depreciation.

This article provides general information about auto insurance rating factors and is not a substitute for advice from a licensed insurance professional. Practices vary by state and insurer.