How PlainInsurer's A-F reputation grades work

What goes into the grade

The composite score behind every letter grade combines up to three components, each used only when real data exists for that insurer: the NAIC complaint ratio (the primary component for every insurer, comparing justified complaints to market share against the industry median), the CMS claim-denial rate (for health insurers, from Transparency in Coverage filings), and the prior-authorization denial rate (for Medicare Advantage plans specifically, compared to peer plans). When a component is unavailable for an insurer, the grade is computed from whichever components do exist rather than estimating the missing one.

Why the grade is relative, not absolute

The composite score maps to a letter grade using a bell-curve distribution across the full graded insurer population, not a fixed point scale. That means a grade tells you how an insurer stacks up against its peers right now, not whether it clears some universal bar. It also means the boundary between, say, a B and a C can shift slightly as the underlying population and data are refreshed, the same way a curved exam score would.

What a high grade does and doesn't mean

An A means an insurer's complaint volume and denial behavior compare favorably to its peers in the same lines of business. It does not mean the insurer never denies claims, has no complaints, or is the cheapest option, and it is not a guarantee about your specific policy or claim. Financial strength, premium cost, coverage terms, and network adequacy are separate questions the grade does not answer.

What a low grade does and doesn't mean

An F means an insurer's NAIC and CMS data compare unfavorably to peers, more complaints or denials relative to size than most competitors in the same lines. It is a population-level signal built from regulator-reported data, not a claim that any specific policyholder will have a bad experience, and not a legal finding of wrongdoing. Some low-graded insurers may still be the right fit for a specific need; use the grade as a starting point for further research, not a final verdict.

How to use the grade when comparing insurers

Compare grades only within the same line of business, a health insurer's grade is not comparable to an auto insurer's, since the underlying complaint and denial baselines differ by line. Read the grade alongside the insurer's specific complaint index and, where available, claim-denial rate on its profile page, rather than the letter alone. Cross-reference with independent financial-strength ratings (AM Best, S&P) for a fuller picture, since the reputation grade does not measure an insurer's ability to pay claims long-term.