How is workers' comp premium calculated in Arizona?

The base formula is payroll divided by 100, multiplied by the class-code rate, multiplied by your experience modifier. For example, $200,000 of payroll at a $1.50 rate and a 1.00 mod is (200,000 / 100) x 1.50 x 1.00 = $3,000 per year before any carrier-specific fees.

What is an experience modifier?

The experience modifier (or mod) compares your company's claim history to the average for your industry. A mod of 1.00 is average; below 1.00 means fewer claims than expected and a discount; above 1.00 means more claims and a surcharge. Small employers often start at 1.00 until they qualify for experience rating.

Where do I find my class code base rate?

Class-code rates per $100 of payroll come from rating bureaus and your insurer. Arizona is a competitive-rating state, so carriers file their own rates rather than using a single state rate. Your insurance agent, CopperPoint, or another carrier can give you the exact rate for each job classification.

Does Arizona require workers' compensation insurance?

Yes. Arizona requires nearly all employers with one or more employees to carry workers' compensation coverage. Employers can buy from private carriers or the state-affiliated fund (CopperPoint). Failure to carry coverage can lead to penalties and personal liability for injury costs.

Why does my actual premium differ from this estimate?

This tool shows the manual premium from the core formula. Real bills can include schedule credits or debits, expense constants, terrorism and catastrophe charges, premium discounts for size, and assigned-risk surcharges. Treat the result as a planning estimate and confirm with a carrier quote.

Arizona Workers' Compensation Premium Calculator

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The Arizona Workers’ Compensation Premium Calculator estimates your annual workers’ comp insurance cost. The core formula multiplies payroll per $100 by the job class-code rate and your experience modifier. Arizona is a competitive-rating state, so carriers file their own rates and you supply the class rate. The result is the manual premium before carrier-specific credits and fees.

How it works

Premium is built from three inputs:

premium = (annual payroll / 100) x class rate x experience mod

mod = 1.00  -> average claim history
mod < 1.00  -> fewer claims, a discount
mod > 1.00  -> more claims, a surcharge

You can add several classifications by running each payroll and rate, then summing. The experience modifier scales the whole result up or down based on your company’s claim record.

Example and notes

$200,000 of payroll at a $1.50 class rate with a 0.90 mod:

manual:  (200,000 / 100) x 1.50 = $3,000
modified: 3,000 x 0.90 = $2,700 per year

A 1.20 mod on the same payroll would instead give 3,000 x 1.20 = $3,600.

Class rates per $100 vary widely by job risk — clerical is low, roofing is high.
Arizona requires coverage for nearly all employers with employees.
Real bills add expense constants, discounts, and surcharges — confirm with a carrier. Runs in your browser.