Two drivers live on the same street. Same car, same age, same clean driving record, same coverage limits. One pays about $1,600 a year for full coverage. The other pays close to $3,200.
The difference is not how they drive. It is what their credit reports look like.
This surprises people, and it should. Nothing about your payment history tells an insurer whether you can merge safely. But credit-based insurance scoring has been standard practice in most of the country for more than two decades, and it moves premiums more than almost any other factor except a serious accident or a DUI. Here is how the mechanism actually works and what you can do about it.
What a Credit-Based Insurance Score Is
Start with what it is not. It is not your FICO score, the one a mortgage lender pulls. It is a separate score, built from the same underlying credit file but weighted for a completely different question.
A lending score is trying to predict one thing: will this person repay borrowed money? A credit-based insurance score is trying to predict something else entirely: how likely is this person to file a claim, and how expensive will that claim be?
Insurers build these scores from familiar ingredients. Payment history carries the most weight, followed by outstanding debt relative to available credit, the length of your credit history, how much new credit you have applied for recently, and the mix of account types you carry. The best known versions come from LexisNexis and FICO, and the exact formulas are proprietary, which is part of why the whole thing frustrates consumers.
Some things are explicitly excluded. Your income does not go into the score. Neither does your race, ethnicity, religion, or where you live, at least not directly. Insurers are barred by the Fair Credit Reporting Act and by state insurance codes from using several categories outright.
The industry’s defense is statistical rather than moral. Actuaries found a durable correlation: as a group, people with lower credit-based insurance scores file more claims and file costlier ones. Nobody has produced a clean causal explanation for why. Insurers argue they do not need one, because insurance pricing has always been about correlation. Critics argue that pricing people on a correlation nobody can explain, using a formula nobody can see, is exactly the problem.
How Much Money Is Actually at Stake
More than most people expect.
Analyses of rate filings across the country find that drivers with poor credit pay roughly 98% more for full coverage than drivers with good credit. Widen the gap to the extremes and it gets worse: comparing exceptional credit to very poor credit, the spread reaches into the hundreds of percent, which in dollar terms can mean thousands of dollars a year on the same policy for the same car.
For context, the national average for full coverage sits around $2,237 a year as of August 2026, according to Insurify’s tracking. So a credit-driven penalty is not a rounding error on a small bill. It is often larger than the difference between insuring a compact sedan and insuring a luxury SUV.
Compare that to the things people actually worry about. A single speeding ticket typically raises a premium by 20% to 25%. An at-fault accident, somewhere around 40% to 50%. A poor credit-based insurance score can outweigh both of those combined, and unlike a ticket, it never appeared as a moment you can point to and regret.
The Legal Map Is Shifting
Four states ban the practice for auto insurance entirely: California, Hawaii, Massachusetts, and Michigan. If you live in one of them, your credit file does not touch your premium.
Several others restrict it partially. Maryland, Oregon, and Utah impose meaningful limits, and Pennsylvania, North Carolina, and Nevada constrain specific uses, such as barring insurers from cancelling or non-renewing a policy solely because of credit.
The interesting development is legislative. During 2026, lawmakers in Iowa, New York, Oklahoma, and Pennsylvania introduced bills that would prohibit insurers from using credit-based insurance scores to price auto policies, homeowners policies, or both. CNBC reported in April on the renewed scrutiny, which is being driven partly by the sharp premium increases of the past few years and partly by consumer advocates arguing the practice compounds existing financial hardship. Someone who lost a job, fell behind on cards, and watched their score drop then gets charged more for the car they need to get to the next job.
Insurers push back hard on these bills, and most do not pass. But the number of states looking at it is higher than it has been in a while, so this map may not look the same in three years.
The Notice You Probably Threw Away
Under the Fair Credit Reporting Act, if an insurer charges you more or declines to cover you based even partly on information in your credit report, it has to send you an adverse action notice. That notice must tell you which credit bureau supplied the data and that you can request a free copy of the file.
Most people open it, register it as insurance junk mail, and recycle it.
It is worth reading. The notice is your entry point into checking whether the underlying data is right, and credit report errors are not rare. A Federal Trade Commission study found that about one in five consumers had a verified error on at least one of their three reports, and roughly 5% had errors serious enough to raise the prices they paid for credit products. If a closed account is reporting as delinquent, or someone else’s debt landed on your file, that mistake is quietly showing up in your insurance bill every six months.
You can pull all three reports free at AnnualCreditReport.com, the site authorized under federal law. Dispute anything wrong. If the correction goes through, ask your insurer to re-rate the policy rather than waiting for renewal.
What Moves the Number
Because insurance scores lean on the same data as lending scores, the same habits help both.
Pay on time, every time. Payment history is the heaviest input, and a single 30-day late mark can linger on your file for seven years. Setting up autopay for at least the minimum on every account is the cheapest insurance against your own busy week that exists.
Keep balances low relative to limits. Utilization is a large second input, and it updates monthly, which makes it one of the faster levers available. Paying a card down before the statement closes rather than after can move the reported number meaningfully.
Do not close old accounts you have had for years just to tidy up. Length of history counts, and closing a long-standing card shortens your average account age and cuts your available credit at the same time.
Space out new credit applications. A cluster of inquiries reads as financial stress in these models, whether or not it feels that way to you.
None of this is fast. Credit-based insurance scores respond over months, not weeks. But the payoff compounds, because the same improvement that lowers your car insurance also tends to lower your homeowners or renters premium, since most insurers use credit there too.
The Practical Move Right Now
Shop the policy. Insurers weight credit differently from one another, and a few, including some regional carriers and at least one large national one, do not use it at all in states where opting out is permitted. The driver who is penalized hardest by one company’s formula may be priced normally by another’s.
Getting three or four quotes takes about half an hour and is the single highest-return financial chore available to most households, credit issues or not. Do it every two years, and do it any time your credit picture changes noticeably in either direction.
And check the report first, so you know whether you are shopping around a real number or an error.