The Core Factors Insurers Use to Set Your Rate
Auto insurance premiums are not arbitrary. Every insurer uses a set of underwriting factors — some within your control, others not — to estimate how likely you are to file a claim and how costly that claim might be. Here is what carries the most weight.
| Primary rating factor | Driving history (accidents, violations) |
| Average US annual premium | Approximately $1,700–$2,100 (varies widely by state) (National Association of Insurance Commissioners data) |
| Violation surcharge period | Typically 3–5 years |
| States banning credit scoring | California, Hawaii, Massachusetts |
| High-risk driver categories | Teen drivers, DUI history, frequent at-fault accidents |
| Deductible range (common) | $250 to $2,000 |
Driving History
Your record is one of the most influential inputs. At-fault accidents, speeding tickets, DUI convictions, and other moving violations signal elevated risk and typically raise your rate for three to five years, depending on the infraction and your state's rules.
Vehicle Type
The car you drive affects what the insurer expects to pay out. Factors include the vehicle's repair cost, safety ratings, theft rate, and engine size. Sports cars and luxury vehicles generally cost more to insure than economy sedans or family crossovers with strong safety scores.
Annual Mileage
More time on the road means more exposure to accidents. Drivers who commute long distances or frequently travel for work are statistically involved in more incidents than low-mileage drivers, and most insurers price accordingly.
Location
Insurers rate risk by ZIP code. Dense urban areas with higher accident frequency, vehicle theft rates, and severe weather exposure typically carry higher premiums than rural areas. State minimum-coverage requirements also vary, which affects base rates directly.
Additional Variables That Shape Your Premium
Beyond the basics, a range of secondary factors contributes to the final number on your declarations page.
Underwriting
The process an insurer uses to evaluate the risk of insuring a driver or vehicle and determine an appropriate premium. It involves analyzing personal, vehicle, and location data against actuarial models.
Declarations Page
The summary page of your auto insurance policy listing your coverage types, limits, deductibles, and premium amounts. It serves as a quick reference for what your policy actually provides.
Deductible
The dollar amount you agree to pay out of pocket before your insurer covers the remainder of a covered claim. A higher deductible usually lowers your premium.
Credit-Based Insurance Score
A scoring model, separate from a standard credit score, that insurers use in most US states to help predict the likelihood of future claims. It is derived from credit report data but weighted differently than a lending score.
Actuarial Data
Statistical data — collected from large populations over time — that insurers use to estimate the probability and cost of future claims for different driver and vehicle profiles.
Credit-Based Insurance Score
Most states allow insurers to use a credit-based insurance score — distinct from your standard FICO score — as a rating factor. Research has consistently shown a statistical correlation between credit profile and claim frequency, though the practice remains controversial. A small number of states, including California, Hawaii, and Massachusetts, prohibit its use in auto insurance pricing.
Age and Driving Experience
Teen and young adult drivers pay substantially higher premiums due to inexperience. Rates typically decrease through the mid-20s as a clean record accumulates. Older drivers — generally those over 70 — may see modest increases tied to actuarial data on collision risk.
Marital Status
Married drivers statistically file fewer claims than single drivers, and many insurers reflect this with a small rate reduction.
Coverage Selections and Deductibles
The coverage types you choose and the deductible amounts you set have a direct, mechanical effect on your premium. Electing a higher deductible — the amount you pay out of pocket before insurance kicks in — lowers the insurer's exposure and reduces your monthly cost, but shifts more financial risk to you. See our guide to choosing between liability and full coverage for a fuller discussion of those trade-offs.
Lapses in Coverage
A gap in your insurance history — even a brief one — can raise your rate with a new insurer, as it is treated as an increased risk signal. Maintaining continuous coverage, even at a minimum level, generally works in your favor when you shop for a new policy.
~25%
Premium increase after a single at-fault accident
Industry data consistently shows a significant rate increase following an at-fault claim, though the exact figure varies by insurer and state.
3–5 years
Typical surcharge window for a DUI conviction
Most insurers apply elevated rates for three to five years following a DUI, with some states mandating specific minimum periods.
~$480
Estimated annual savings from doubling a deductible
Moving from a $500 to $1,000 deductible can reduce comprehensive and collision premiums meaningfully, though savings vary by policy.
Auto insurance is a meaningful share of total vehicle ownership expense. For a broader look at every cost category involved, see our breakdown of the true cost of owning a car in the US. If you want to understand exactly what your premium is buying, our plain-language guide to policy coverage types explains each component. And for practical strategies to keep insurance costs in check over time, visit our article on keeping vehicle ownership costs manageable.
This article provides general information about auto insurance pricing factors and is not a substitute for personalized advice from a licensed insurance professional. Premium factors and regulations vary by state; verify current rules with your insurer or state insurance commissioner.
