Inputs
Formula used
- Annualized payroll = payroll × period multiplier
- Manual premium = Σ[(Annual payroll ÷ 100) × Rate]
- After X‑Mod = Manual premium × Experience mod
- After schedule = After X‑Mod × (1 + Schedule% ÷ 100)
- After deductible = After schedule × (1 − Deductible% ÷ 100)
- After discount = After deductible × (1 − Discount% ÷ 100)
- Surcharge amount = After discount × (Surcharge% ÷ 100)
- Base before assessments = After discount + surcharge + flat fees
- Assessment amount = Base before assessments × (Assessment% ÷ 100)
- Final estimate = max(Base + assessment, Minimum premium)
How to use this calculator
- Select payroll period, then enter payroll on that basis.
- Add one row per class code with payroll and rate.
- Enter modifiers like X‑Mod, schedule, and deductible credit.
- Use discount and surcharge fields for scenario planning.
- Click Calculate to see totals and the chart.
- Export CSV or PDF for documentation and sharing.
Example data table
| Class Code | Role | Payroll | Rate / $100 | X‑Mod | Manual Premium |
|---|---|---|---|---|---|
| 8810 | Clerical office | 250,000 | 0.35 | 0.95 | 875.00 |
| 8742 | Outside sales | 180,000 | 0.55 | 1.00 | 990.00 |
| 5190 | Electrical work | 420,000 | 3.80 | 1.10 | 15,960.00 |
Premium drivers and why payroll matters
Workers compensation pricing starts with payroll exposure. The calculator annualizes payroll (annual, monthly×12, weekly×52) and applies each class rate per $100 of payroll. For example, $420,000 payroll at $3.80 produces a $15,960 manual premium before modifiers.
How class codes change the base premium
Mixed operations usually require multiple class lines. Separating clerical (often lower rates) from field work (often higher rates) improves precision. If 30% of payroll shifts from a $3.80 class to a $0.35 class, manual premium can drop materially, even with the same total payroll.
Modifiers and credits in a typical sequence
The tool applies Experience Mod (X‑Mod), Schedule credit/debit, Deductible credit, then an optional Premium discount. A 1.10 X‑Mod increases the manual premium by 10%. A −5% schedule credit then reduces the modified amount, and a 10% deductible credit reduces it further.
Fees, assessments, and minimum premium impacts
Flat charges such as an expense constant and other fees are added before assessments. Assessments are modeled as a percentage of the subtotal. If the estimated total is below the minimum premium, the calculator shows the minimum add‑on so you can see the exact gap.
Scenario testing using charts and exports
Use the stage chart to see each rating step, the breakdown donut for component shares, and the sensitivity line to estimate how rate changes affect totals. Export CSV for audit trails and create a PDF for internal approvals or broker discussions.
FAQs
1) What does “rate per $100” mean?
It means premium is charged per $100 of payroll. The calculator computes (annual payroll ÷ 100) × rate for each class line, then sums the manual premium.
2) Why do I need multiple class lines?
Different job types can have different rates. Using separate class lines prevents low‑risk payroll from being priced at higher rates, and it improves the accuracy of planning scenarios.
3) What is the Experience Mod (X‑Mod)?
X‑Mod is a factor that adjusts the manual premium based on historical loss experience. Values above 1.00 increase premium; values below 1.00 reduce it.
4) How are schedule credits and deductible credits applied?
This calculator applies schedule adjustment after X‑Mod and applies deductible credit after schedule. Some carriers may sequence differently, so treat results as estimates.
5) What does the sensitivity chart show?
It models total premium if class rates move from −20% to +20%, holding payroll, modifiers, fees, and assessments constant. It helps you understand rate risk.
6) Is this a binding quote?
No. It is a planning calculator. Actual premiums can vary due to carrier rules, state programs, audits, rounding, limits, and additional endorsements or surcharges.