How Car Insurance Quotes Are Calculated

Key takeaways

• A quote is an estimate of your premium, based on the risk an insurer expects to cover and the coverage you choose.
• Common rating factors include your driving record, experience, vehicle, garaging address, mileage and, in most states, a credit-based insurance score.
• Every insurer weighs those factors its own way, which is why the same driver can receive very different quotes.
• A quote isn't final until the insurer verifies your information, so accuracy up front matters.

What a quote actually is

A car insurance quote is an insurer's estimate of what it would charge to cover you, your vehicles and the other drivers in your household for a set period, usually six or twelve months. That price is called the premium. It rests on two things: how likely the insurer thinks a claim is and how costly that claim might be, and how much protection you ask the policy to provide.

A quote is not a contract. It reflects the answers you gave, and it can change once the insurer checks those answers against outside records. More on that below.

The factors about you and your driving

Insurers price policies using rating factors: pieces of information that, based on each company's own claims experience, help predict future losses. The exact list depends on the company and the state, but most quotes weigh some version of the following.

Driving record and claims history

At-fault accidents, speeding tickets and serious violations such as driving under the influence tend to raise premiums, often for several years. Insurers commonly look back three to five years, though the window varies. Many also check shared claims-history databases, so a claim made with a previous insurer can still show up.

Experience and age

Newly licensed drivers, especially teenagers, usually pay more because inexperience is linked with more crashes, and rates often ease as drivers build a record. Some states restrict how insurers may use personal characteristics such as age, gender or marital status, so the factors in play depend partly on where you live.

Credit-based insurance score

In most states, insurers may use a credit-based insurance score. It is built from information in your credit report, but it is not the same number a lender sees. A few states, including California, Hawaii and Massachusetts, bar or sharply limit its use in auto insurance. Because the score draws on your credit report, it is worth making sure the report is accurate.

The factors about your car

The vehicle matters in several ways. A car that costs more to repair or replace generally costs more to insure for collision and comprehensive coverage. Models that are stolen often, or whose parts are expensive, can carry higher comprehensive rates. Safety equipment and crash protection can influence the injury-related parts of the premium. Insurers usually identify the exact vehicle from its VIN (vehicle identification number), so it helps to have it ready.

Where and how you drive

Your garaging address, meaning where the car is usually parked overnight, carries real weight. Traffic density, theft and vandalism, weather, local repair costs and how often claims end up in court all vary from one ZIP code to the next. Two otherwise identical drivers living a few miles apart can receive noticeably different quotes.

How much and why you drive counts too. A long daily commute means more time on the road than occasional weekend trips, and business use can be rated differently from personal use. Some insurers offer optional usage-based programs that measure actual driving through an app or a plug-in device. How that data is used, and whether it can raise a price as well as lower it, differs by insurer and state, so read the program terms before enrolling.

The coverage you choose

The other half of the price is under your control: what the policy covers and how much it will pay.

• Liability limits. Higher limits cost more but protect you further if you cause a serious crash. They are often written as three numbers, such as 100/300/100; our guide to coverage types explains how to read them.
• Deductibles. The amount you pay toward a collision or comprehensive claim. A higher deductible usually means a lower premium, as our deductible guide explains.
• Optional coverages. Rental reimbursement, roadside assistance and similar add-ons each add to the total.
• Drivers and vehicles. Every licensed household member and every car listed on the policy affects the price.

How discounts fit in

Most insurers offer discounts, for example for bundling home and auto policies, insuring several cars, keeping a clean record, good grades for student drivers, completing an approved defensive-driving course, paying in full or choosing paperless billing. Availability and amounts vary by company and state, and discounts are applied inside the insurer's rating plan rather than taken off a fixed sticker price. It is reasonable to ask each insurer which discounts you qualify for and whether they are already reflected in the quote.

From quote to final premium

Before a policy is issued, the insurer typically verifies what you told it. That can include pulling your motor vehicle record from the state, checking claims history, confirming each vehicle by VIN and, where allowed, obtaining an insurance score. If anything differs from your application, such as a ticket you forgot or a driver you didn't list, the price can change. Being complete and accurate up front is the surest way to get a quote that holds.

Premiums can also change at renewal even if nothing about you has changed, because insurers periodically revise their rates as claim costs rise or fall.

Before you request a quote

Having these on hand makes quotes faster and more accurate:

• Driver's license numbers and dates of birth for every driver in the household
• Each vehicle's VIN, or at least its year, make, model and trim
• Your current policy's declarations page, if you have one
• A realistic estimate of annual mileage for each car
• Dates and details of any accidents, claims or violations in recent years

Helpful official resources

Independent public resources for going further. AutoQB is not affiliated with any of these organizations.

• National Association of Insurance Commissioners (NAIC)The organization of the chief insurance regulators of the 50 states, the District of Columbia and the U.S. territories.
• AnnualCreditReport.comThe federally authorized source for free copies of your credit reports from the three nationwide credit bureaus.
• Consumer Financial Protection Bureau (CFPB)The federal agency responsible for consumer protection in the financial sector.
• USA.govThe official web portal of the U.S. government.

This guide is general educational information about how car insurance commonly works in the United States. Coverage terms, rules and requirements vary by state and by insurer, so your policy documents, your insurer or agent, and your state insurance department are the authorities for your situation.