Workers’ Comp Audit and Payroll Review

A workers’ compensation policy is priced on estimated payroll and settled on actual. At expiration the carrier audits you, reconciles what you reported against what you paid, and sends either a bill or a refund.

Most employers treat that as an administrative event. It isn’t. It is the point where classification errors, undocumented splits and missing subcontractor certificates all become money, usually in the carrier’s favour, and usually twelve months after you could have done anything about it.

What Counts as Payroll, and What Doesn’t

The default rule is broad. With specific exceptions, all money and substitutes for money earned during the policy period by covered employees and officers is payroll: gross wages, salaries, commissions, bonuses, overtime payments, the market value of gifts, and vacation, holiday and sick pay.

The exceptions are where the money is.

The overtime rule, which costs employers real money

The premium portion of overtime pay, the extra half or full rate above regular pay, can be excluded from reportable payroll. But the exclusion is conditional. You have to maintain records showing, separately by employee and in summary by type of operation, either:

• Remuneration earned at regular rates of pay for all hours worked, plus the premium portion of overtime pay, or
• Remuneration earned at regular rates for all non-overtime hours worked, and total remuneration earned for overtime hours

If your payroll system reports a single lump overtime figure, you do not meet the condition, and the whole amount goes in at full value.

Where Audits Go Wrong

Uninsured subcontractors. No valid certificate covering the dates a sub actually worked and the auditor can charge their payroll to you at your classification rate. This is the largest single source of surprise audit bills for contractors.

Payroll not split by class. When records don’t support a split between classifications, the auditor can assign all of it to the highest-rated code that applies. Documentation is what protects the lower rate.

Dual wage splits without records. Construction dual wage classifications depend on the regular hourly wage, and a credit that isn’t documented gets reversed.

Clerical and outside sales not separated where the Standard Exception rules permit it.

Officer and partner payroll outside the limits. Included officers, partners, individual employers and LLC members are subject to annual minimums and maximums. Effective September 1, 2026 that range is $66,300 to $171,600. Reporting an officer’s actual draw below the minimum or above the maximum produces the wrong number in both directions.

Classification maxima ignored. Several classes cap individual payroll, and the cap has to be applied per employee rather than to the total.

Estimates left stale. If your estimated payroll is well below actual, you carry an audit balance. If it’s well above, you financed the carrier interest-free all year.

What We Do

• Pre-audit preparation. We go through your records before the auditor does and tell you what is missing while there is still time to fix it.
• Payroll reporting setup. Getting the overtime split, class splits and officer treatment configured correctly at the start of the term, which is when it has to happen.
• Subcontractor certificate process. A system for collecting and refreshing certificates, filed by job, so the auditor finds nothing to charge.
• Audit dispute support. Reviewing a completed audit against the rules and pushing back where it is wrong. The WCIRB also maintains a Policyholder Ombudsman who assists employers with questions and disputes about payroll and remuneration rules.
• Mid-term payroll review. Catching a drifting estimate at six months rather than at expiration.
• Classification review. Confirming the codes on the policy match what your people actually do.

How to Prepare

1. Payroll records by employee and by class, with overtime broken out the way the rule requires.
2. Quarterly tax filings that reconcile to your payroll register.
3. Certificates of insurance for every subcontractor, covering the exact dates they worked.
4. A job or assignment log tying employees to the work performed, which is how a class split survives scrutiny.
5. Cash disbursement records, since payments to individuals outside payroll will be looked at.
6. Officer and partner compensation detail.

Organised records are not only about compliance. An auditor handed a clean file works from your numbers. An auditor handed a shoebox builds their own.

Related Reading

• Seven audit mistakes that can cost your business thousands
• How your X-Mod is actually calculated
• Five practical ways to lower your workers’ comp costs

This page is general information about California workers’ compensation payroll reporting and audits. It is not legal or accounting advice. Payroll rules, thresholds and limits are set by the Uniform Statistical Reporting Plan and change over time; verify current figures with the WCIRB or your broker.