What Is Car Insurance?

Car insurance is a contract between you and an insurer: you pay a premium, and in exchange the insurer agrees to cover certain costs after an accident or other covered event — repairing or replacing vehicles, paying medical bills, or compensating other people for damage you're responsible for, up to the limits of your policy.

How it works

You choose (or your state requires) a set of coverages and limits, and pay for them as a premium, usually monthly, quarterly or annually. If something covered happens — a collision, a theft, an at-fault accident that hurts someone else — you file a claim, and the insurer pays out according to what your policy actually covers, minus any deductible you agreed to. Nearly every state requires drivers to carry at least some minimum coverage; see what happens if you don't for the one well-known exception and the consequences of skipping it.

The main types of coverage

Most policies are built from a handful of coverage types, each protecting against something different:

• Liability pays for injuries and property damage you cause to others — it's the coverage almost every state requires, and it doesn't pay for your own car or injuries.
• Collision and comprehensive pay to repair or replace your own vehicle, whether from a crash, theft, weather, or hitting an animal.
• Medical payments and personal injury protection cover medical costs for you and your passengers regardless of fault.
• A handful of other coverages — rental reimbursement, roadside assistance, gap insurance, SR-22 filings, non-owner policies — fill in specific gaps. See our full guide to coverage types for how each one works.

Where to go deeper

This page is a starting point — the rest of the site covers each part of the system in more depth:

• Coverage types explained — liability, collision, comprehensive, PIP, gap, SR-22 and more.
• Tort vs. no-fault — how your state decides who pays after an accident.
• How a policy works — quotes, binders, declarations pages and grace periods.
• Premiums, deductibles and limits — the core cost vocabulary.
• How insurers rate and price drivers.
• What determines your cost — and how to lower it.
• How claims work, and what to do if yours is denied.
• State-by-state guides — current minimum coverage requirements and typical costs by state.

AutoInsuranceQuery editorial team. Last reviewed: September 16, 2026.