Workers' Comp Class Code Lookup

Workers' compensation class codes are four-digit numerical codes assigned by the National Council on Compensation Insurance (NCCI) to classify businesses based on the type of work their employees perform. Each code corresponds to a specific occupational category and carries a base rate that reflects the historical risk of workplace injuries for that type of work.

Insurance carriers use these codes to calculate workers' comp premiums. The formula is straightforward: Premium = (Payroll / 100) x Rate x Experience Mod. Accurate classification is critical because misclassification can result in audit penalties, unexpected premium adjustments, or coverage gaps.

Hazard Groups Explained

NCCI assigns each class code to a hazard group ranging from A (lowest risk) to G (highest risk). Hazard groups influence the experience rating calculation and help carriers assess relative risk across different industries.

• Group A — Lowest hazard. Clerical, office, professional roles (e.g., 8810 Clerical Office Employees).
• Group B — Low hazard. Light manufacturing, retail, outside sales (e.g., 8742 Outside Salespersons).
• Group C — Moderate hazard. General manufacturing, warehousing, food service (e.g., 9079 Restaurant NOC).
• Group D — Above average hazard. Heavy manufacturing, trucking, plumbing (e.g., 5183 Plumbing NOC).
• Group E — High hazard. Steel fabrication, concrete construction, excavation (e.g., 5213 Concrete Construction).
• Group F — Very high hazard. Roofing, mining, structural steel erection (e.g., 5551 Roofing).
• Group G — Highest hazard. Underground mining, high-rise steel erection, explosives (e.g., 5040 Iron or Steel Erection - Frame Structures).

Common Classification Tips for Agents

• Governing class code — The code that represents the largest portion of the insured's payroll usually becomes the governing class for experience rating.
• Standard exceptions — Codes 8810 (Clerical) and 8742 (Outside Sales) can be split from the governing class if employees work exclusively in those capacities.
• NOC codes — “Not Otherwise Classified” codes are catch-all classifications. Use them only when no more specific code applies.
• State exceptions — Some states (California, New York, Pennsylvania, and others) maintain their own rating bureaus and may use different codes or descriptions.
• Dual classifications — A single employer may have multiple class codes if employees perform distinctly different types of work (e.g., office staff vs. field crews).