NCCI vs. Independent Rating Bureaus

The National Council on Compensation Insurance (NCCI) is a licensed rating, advisory, and statistical organization that develops and files loss costs, maintains the classification system, and calculates experience modification rates for the majority of U.S. states. Insurance carriers use NCCI's data and rules as the foundation for how they rate workers' comp policies in those states, though individual carriers still apply their own pricing on top of the NCCI-developed loss cost.

NCCI also maintains the residual market — the mechanism that ensures coverage is available to employers who can't find a carrier willing to write them voluntarily, often because of a difficult loss history or an unusually hazardous class code. This assigned-risk mechanism exists precisely because workers' comp coverage is mandatory in most states: an employer that can't get quoted voluntarily still needs a path to compliant coverage, and the residual market is that path.

A number of states chose, often decades ago, to establish their own independent rating bureau instead of relying on NCCI, typically to keep classification and rating decisions closer to that state's own regulator and market conditions. These bureaus perform the same core functions NCCI performs elsewhere — maintaining class codes, filing loss costs, and calculating experience mods — but do so using their own data, their own class code numbering in some cases, and their own filing process with that state's insurance regulator.

The historical reasons vary by state, but a common thread is that larger, more heavily industrialized states with substantial in-state claims data concluded they could produce more locally accurate loss costs by analyzing their own market directly, rather than folding their data into a nationwide pool. Whether that produces a meaningfully different outcome for any individual policy is hard to generalize, but the institutional separation itself is real and affects how classification disputes and rate filings are handled.

States with their own independent rating bureau include:

Ohio, alongside North Dakota, Washington, and Wyoming, is a monopolistic state, which is a different concept entirely from an independent bureau state. In a monopolistic state, coverage is purchased only through the state fund rather than private carriers, and Ohio's own agency — the Ohio Bureau of Workers' Compensation (Ohio BWC) — administers rating and claims directly rather than through a separate advisory bureau serving multiple competing private carriers. See our guide to workers' comp for new businesses and our state pages for how Ohio's system differs in practice.

The practical effect for a business is mostly about where your class code and experience mod come from, and who you'd appeal to if you disagreed with either. In an NCCI state, disputes and classification questions generally route through NCCI's process alongside your carrier. In an independent bureau state, the state's own bureau — not NCCI — is the authority on your classification and experience mod calculation. Multi-state employers should expect to interact with more than one system if they operate in both NCCI states and independent bureau states.

This becomes especially relevant during a dispute. If you believe your class code or experience mod was calculated incorrectly, knowing which organization actually governs that calculation for the state in question determines where you'd direct a formal inquiry or correction request — your carrier can often help facilitate this, but the underlying authority sits with NCCI or the relevant independent bureau, not with the carrier itself.

Not fundamentally — a carrier operating in an independent bureau state still uses that bureau's loss costs and class codes as the foundation for its rate, the same way it would use NCCI data elsewhere. What changes is the data source and filing process behind the number you see, not the basic structure of how your policy is priced.

One practical difference worth knowing: class code numbering itself can differ slightly between an independent bureau and NCCI for a conceptually similar operation, since each bureau develops its own classification system rather than adopting NCCI's numbering wholesale. A code that looks unfamiliar on a policy issued in an independent bureau state isn't necessarily an error — it may simply be that bureau's own numbering for the same type of work.

Most employers never think about which organization sits behind their rate, because it doesn't appear anywhere prominent on a policy or a quote — it's infrastructure, not a customer-facing feature. It tends to surface only in specific moments: a dispute over a classification, a question about why a mod calculation looks different from what a national benchmark might suggest, or a multi-state renewal where the same job function is coded differently from one location to the next. Knowing the distinction exists means you're not caught off guard the first time it does come up.

If your business operates in a mix of NCCI states and independent bureau states, a single application can still be compared across carriers licensed in each, without needing to run a separate shopping process state by state. Get Multiple Quotes within minutes and see how your specific class codes are treated wherever you operate.