Calculate workers compensation insurance premiums using payroll, class code rates, and experience modification rate (EMR) factors.
Workers compensation insurance is required in nearly every state and covers medical expenses, lost wages, and rehabilitation for employees injured on the job. Premiums are calculated based on your total payroll, the class code rate for each job type, and your experience modification rate (EMR).
This calculator uses the standard workers' comp formula: Premium = (Payroll / $100) × Class Rate × EMR. Different employee classifications carry different rates — office workers might be $0.20 per $100 of payroll while roofers could be $20+ per $100. Your EMR reflects your claims history compared to similar businesses.
This is an educational estimate only. Actual premiums depend on your state, specific class codes, premium discounting tiers, assigned risk surcharges, and carrier-specific modifications. Work with a licensed workers' comp specialist for accurate quotes. Whether you are a beginner or experienced professional, this free online tool provides instant, reliable results without manual computation. By automating the calculation, you save time and reduce the risk of costly errors in your planning and decision-making process.
Workers' comp is mandatory in most states, and premiums can be a significant expense — especially for construction, manufacturing, and healthcare employers. Understanding the rating formula helps you budget accurately, identify opportunities to reduce costs, and verify your carrier's calculations at audit time. Having a precise figure at your fingertips empowers better planning and more confident decisions.
Manual Premium = (Annual Payroll / $100) × Class Code Rate Modified Premium = Manual Premium × EMR Estimated Annual Premium = Modified Premium (Actual policies may include premium discounts, expense constants, and state surcharges)
Result: $16,625/year
Manual premium: ($500,000 / $100) × $3.50 = $17,500. Modified by EMR 0.95: $17,500 × 0.95 = $16,625. The below-average EMR saves $875 compared to a 1.0 EMR.
Workers compensation uses a straightforward but layered rating approach. The foundation is payroll classified by job type, multiplied by a rate that reflects injury frequency and severity for that classification. Your EMR then adjusts the premium based on your actual claim history.
EMR is the single most impactful factor you can control. A business with a 0.80 EMR pays 20% less than average, while a business at 1.30 pays 30% more. EMR is calculated using three years of loss history, so the impact of a bad year persists. Consistent safety investment is the key to a low EMR.
Beyond safety, ensure proper employee classification, exclude eligible owners, consider higher deductibles (in states that allow it), implement a return-to-work program to reduce lost-time claims, and explore group or association programs for potential credit.
The formula is Premium = (Payroll / $100) × Class Code Rate × EMR. Payroll is the exposure base, the class code rate reflects the injury risk of the job type, and the EMR adjusts for your specific claims history.
Class codes group jobs by injury risk. Each code has a rate per $100 of payroll. Office workers (code 8810) might be $0.20, while carpentry (code 5403) might be $8.00. NCCI or your state rating bureau publishes current rates.
An EMR of 1.0 is average for your class and state. Below 1.0 means fewer claims than expected, earning a discount. Above 1.0 means more claims, adding a surcharge. Top performers achieve EMRs of 0.70-0.85.
In most states, sole proprietors, partners, and LLC members can elect to exclude themselves from workers' comp. Corporate officers may opt out in some states but are usually included with minimum/maximum payroll caps.
Your carrier audits actual payroll against the estimate used to set the initial premium. If payroll was higher, you owe additional premium. If lower, you receive a refund. Accurate payroll estimates minimize audit surprises.
Many states have created presumptions that certain workers (healthcare, first responders) who contract COVID did so at work. Coverage varies by state and occupation. Check your state's workers' comp board for current rules.