Classifications
Workers' Compensation class codes are the foundation of every California premium calculation. The WCIRB assigns a four-digit code to each type of job duty, and each code carries a base rate per $100 of payroll. A roofer in Bakersfield, a warehouse worker in Stockton, and a clerical employee in San Francisco all land on different codes — and those codes, multiplied by payroll, drive the premium.
Codes are assigned by the primary work being performed, not by the business name. A plumbing company that also does some clerical work will have separate codes for field plumbers (higher rate) and office staff (much lower rate). Accurate separation of payroll by code is what keeps your premium fair — and what carriers verify during the annual payroll audit.
The WCIRB publishes the classification guide used statewide. Each code describes the scope of work it covers, and carriers rely on that description during underwriting and audits.
Rates vary by code and are adjusted periodically by the WCIRB. Common categories include construction trades (roofing, electrical, plumbing, framing), agricultural field labor, manufacturing operations, trucking, clerical office work, and healthcare. Within construction, even related trades can have meaningfully different rates — residential roofing and commercial roofing can land on different codes.
If your business performs multiple types of work, your agent should help you document how payroll splits across codes. Keep clean time records for employees who move between duties; that documentation is what protects you at audit time.
For a class code review and a statewide quote conversation, visit the California Workers' Comp page or call 916-822-9595 — open 365 days a year, 8am to 9pm Pacific, including all major holidays. For Sacramento-area service, see our Sacramento Workers' Comp page.