Auto & Driving
How Credit Score Affects Insurance Rates
Score methodology sourced from NAIC/FICO, as reported by Insurance.com and cross-confirmed via a second independent source; cost data from Insurify and Insurance.com.
It is not your regular credit score, and it is not one single number pulled from a credit report. Here is the actual formula insurers use, and why it moves your premium so much.
Data sourced from NAIC, FICO
Your insurance score is not your credit score
This is the single most important distinction to understand before anything else. A regular credit score, the kind a lender checks before approving a loan, predicts how likely you are to repay debt.
A credit-based insurance score is a separate, differently weighted calculation built from some of the same underlying credit report data, but designed to predict something different: how likely you are to file an insurance claim.
The two scores are related but not identical, and it is entirely possible to have a strong credit score and a comparatively weaker insurance score, or the reverse.
The actual formula: five factors, unevenly weighted
According to NAIC and FICO's own published methodology, a credit-based insurance score weighs five factors:
- Payment history: 40%
- Outstanding debt: 30%
- Length of credit history: 15%
- Pursuit of new credit: 10%
- Credit mix: 5%
Payment history alone accounts for nearly half the total score, more than the next two factors combined. That single fact has a practical implication: consistently paying every bill on time does more for a credit-based insurance score than almost any other single action, more than paying down debt faster or avoiding new credit applications, both of which do matter but carry meaningfully less weight in this specific formula.
What that formula translates to in real premium dollars
The scoring mechanism matters because of how much it actually moves a premium in states that allow it. Insurify's 2026 analysis of auto insurance found drivers with poor credit paying about 40% more than drivers with excellent credit, nationally.
Insurance.com's homeowners data shows an even wider gap, about 266% more for poor credit versus excellent credit on the same coverage. Both figures represent a genuinely large rating factor, on the scale of some of the biggest factors insurers use at all, not a minor adjustment.
FICO itself estimates that about 95% of auto insurers and 85% of homeowners insurers use credit-based scoring as a rating factor in states where it is legally permitted, so for most drivers and homeowners in most states, this is not a niche or occasional practice, it is closer to the industry default.
To see where your own state stands, since not every state permits this practice, and to run your own numbers by credit tier, the insurance cost by credit score calculator covers both.
What this means practically
Given that payment history alone drives nearly half of a credit-based insurance score, the single highest-leverage action for most people is simply not missing payments, on anything reporting to a credit bureau, not just credit cards.
Paying down existing debt and being deliberate about how often you apply for new credit both help too, just with less individual weight in this specific model than payment history carries on its own.
Frequently asked questions
Is my credit-based insurance score the same as my regular credit score?
No, and this is a genuinely common point of confusion. A regular credit score predicts how likely you are to repay a loan. A credit-based insurance score uses some of the same underlying credit report data, but it is calculated separately, using a different weighting, to predict how likely you are to file an insurance claim.
You can have a strong regular credit score and a different insurance score, and vice versa.
What factors go into a credit-based insurance score?
According to NAIC and FICO's own published methodology, five factors: payment history (40%), outstanding debt (30%), length of credit history (15%), pursuit of new credit (10%), and credit mix (5%).
Payment history alone accounts for nearly half the score, so a history of on-time payments matters more than almost anything else in this specific model.
How much can credit actually move my premium?
By a lot, in states where insurers are allowed to use it. Insurify's 2026 analysis found poor credit costing about 40% more than excellent credit for auto insurance nationally, and Insurance.com's data shows an even wider 266% gap for homeowners insurance between the same two tiers.
Auto insurance is somewhat more consistently studied on this point than home insurance, but both show credit as a genuinely major rating factor where it is permitted.
Do all insurers use credit-based insurance scores?
The large majority do, where state law allows it: FICO itself estimates about 95% of auto insurers and 85% of homeowners insurers use credit-based scoring as an underwriting or rating factor in states where it is legally permitted.
A handful of states ban or restrict the practice entirely, which is covered in more detail in a companion post on this site.