What a rate filing is

A filing is a document, not a price list

The filing contains the rating plan: base rates by coverage, the classification system, every factor and multiplier applied to it, territory definitions, discounts, surcharges and the rules for applying them. Together they form an algorithm. Feed it a driver, a vehicle, an address and a coverage selection and it returns exactly one number, every time, for as long as it stays on file.

The filing also carries an effective date, and it applies to policies written or renewed on or after that date. A driver whose policy renews in March is priced by whatever was on file in March, not by what the insurer filed in July.

Prior approval, file-and-use, use-and-file

Under prior approval the insurer files and waits: the rate cannot be used until the department approves it, and some states deem it approved if the department does not act inside a set period. This gives the regulator the strongest hand and makes the pipeline slowest.

Under file-and-use the insurer files and may use the rate immediately, with the department able to disapprove it afterwards. Under use-and-file the insurer applies the rate first and files it within a stated window. Several states operate flex-rating bands, where a change inside the band is automatic and a change outside it needs approval, and a small number allow competitive rating with no prior filing for most changes.

The label matters less than the practice. A prior-approval state with a well-resourced department can move faster than a file-and-use state in a hostile political environment, and the same insurer can be waiting months in one state while implementing immediately in another.

A filed rate is not an advertised price

An advertisement describing what drivers who switched paid is a claim about a self-selected group, calculated by the advertiser, with nothing lodged anywhere. A filed rate is a document held by the state that determines a premium for defined inputs. Only one of the two can be checked against a public record.

The premium comparison surveys this site aggregates sit on the filing side of that line. Insurers answer the regulator’s hypothetical by running their filed plan, which is why the results reproduce and why they can carry an effective date at all. Across the committed data that is 744,460 filed rates aggregated into 18,789 published distributions.

The lag between a filing and a renewal notice

Approval does not change anybody’s price on the day it happens. Existing policies are repriced at renewal, so a rate change reaches the book gradually across the following policy term, and half a year or a full year can pass before it is entirely in force. Filings are also built on loss data already several months old when they are submitted, which puts a second lag in front of the first.

That double lag is why the published price index turns before the surveys do. The index carries a reading for June 2026, while the oldest survey in this site’s data still carries rates effective March 2023. Both are correct. They are measuring different points in the same pipeline, and reading them as though they described the same moment is how a stale figure gets presented as a current one.

Questions

Does a regulator set insurance prices?

No. Insurers propose rates and the department reviews them against a statutory standard, usually that rates be adequate, not excessive and not unfairly discriminatory. A department can disapprove a filing, but it does not write the rating plan.

How long does a rate change take to reach drivers?

Existing policies are repriced at renewal, so a change spreads across an insurer’s book over a full policy term. Price indexes and published surveys therefore turn at different times, and the gap is structural rather than an error in either.

Are rate filings public?

The rate pages and effective dates are searchable in most states. Supporting actuarial exhibits and scoring models are frequently withheld as trade secrets, so the public record shows the price more readily than the reasoning.