Glossary

Rate filing

The package of proposed rates, rating rules and supporting data an insurer submits to a state regulator when it wants to change prices.

Also called: rate request, rate submission, SERFF filing

A rate filing is how an insurer tells a state regulator what it plans to charge. It contains the proposed base rates, rating factors and rules, along with actuarial support: claim and premium data, trends in loss costs, expense assumptions, and the overall percentage change requested. Most filings are submitted electronically through SERFF, a system run by the NAIC.

What happens next depends on state law. In prior approval states, the insurer must wait for approval before using the new rates. In file-and-use states, it can use them once filed, and the regulator can still order changes later. Everywhere, regulators review whether rates are excessive, inadequate or unfairly discriminatory. A filing usually reports an overall average change, and individual drivers can see larger or smaller ones. Example: a filing for a 9% overall increase might mean 4% in one territory and 15% in another, depending on where claim costs grew (hypothetical figures).

Rate filings are generally public records, and many states let you search them online. Reading one can explain why your premium changed, such as higher repair costs or more severe injury claims. The insurer's loss ratio is often central to its case. See loss ratios and rate filings: how insurers justify an increase.

Last reviewed October 4, 2026

In the index now

Related terms

Insurance rate The price per unit of coverage an insurer files with the state, which rating factors then adjust to produce your individual premium. Prior approval A rate regulation system in which insurers must get the state regulator's approval before using new rates or rating rules. File-and-use A rate-regulation system in which insurers can start charging new rates once they are filed with the state, without waiting for advance approval. Loss ratio The share of premium an insurer pays out in claims, often including claim-handling costs; a key number in rate filings and profit reports. State department of insurance The state agency that licenses insurers and agents, reviews rates and policy forms, monitors solvency and handles consumer complaints. Proposition 103 The 1988 California ballot measure that requires approval of auto rates before use, mandates a Good Driver Discount and made the commissioner elected.

Related guides

California Proposition 103 explained What California's 1988 Prop 103 did: the 20% rollback, prior approval of rates, the Good Driver Discount, ranked rating factors and paid consumer intervenors. How car insurance rates are calculated How insurers build a car insurance price: a filed base rate, multiplied by rating factors for driver, car, place and coverage, then adjusted by discounts. How car insurance rate approval works How states review car insurance rates: prior approval, file-and-use, use-and-file and flex rating, what regulators check, and how to follow a filing yourself. How to research a car insurance company before you buy A step-by-step checklist for vetting a car insurer: confirm its license, check its financial strength and complaint record, and see how it handles claims. Loss ratios and rate filings: how insurers justify an increase How insurers use loss ratios, expense ratios and trend data to justify a rate change, what regulators check, and how to read a filing yourself. The NAIC explained What the National Association of Insurance Commissioners is, how it writes model laws without regulating anyone, and the free NAIC tools drivers can use.

Related tools

Renewal rate increase checker See how much your car insurance renewal went up per year and per month, separate your own changes from a rate increase, and get a list of next steps.