A workers' comp audit is the carrier's year-end true-up of your policy. Your premium was estimated up front on projected payroll; at the end of the policy period the carrier checks it against your actual payroll and operations, then bills you the difference or refunds it. It is a standard, contractual part of almost every workers' comp policy — not a sign that you did anything wrong. The audit only becomes painful when payroll grew, work got misclassified, or a subcontractor can't prove it carried its own coverage. Organized records and clean class-code splits are what keep the true-up honest.
When your policy started, nobody knew exactly what you'd pay in wages over the next twelve months, so the premium was built on an estimate. Workers' comp premium is fundamentally payroll times rate, and payroll only becomes final after the year is over. The audit reconciles the estimate against reality. If you paid more wages than projected — you grew, added a crew, worked more overtime — you owe additional premium. If you paid less, you're owed a refund. This is why the audit is auditable by contract: it's the mechanism that makes the whole pay-for-what-you-actually-owe system work.
Depending on the carrier and the size of your account, an audit can be handled by mail, an online questionnaire, a phone call, or an in-person visit. Smaller policies are usually mail or online; larger or higher-hazard accounts more often get a physical audit. Either way, the auditor is doing the same thing: confirming your payroll totals, splitting that payroll into the correct class codes, and checking your subcontractor documentation. You'll typically have a window of a few weeks to respond, and ignoring an audit request can trigger an estimated audit that assumes the worst — often a large bill you then have to fight to correct.
Having these ready, organized, and consistent with each other is the difference between a clean audit and an inflated one:
Additional premium at audit almost always comes from a short list of causes:
| Cause | What happens | Prevention |
|---|---|---|
| Uninsured subs / 1099s | Their pay is added to your payroll, often at your top rate | Collect a valid certificate before they start |
| Payroll higher than estimate | You owe premium on the extra wages | Update the estimate mid-year if you grow |
| Misclassified work | Wages land in a higher-rated code than they should | Split payroll by type of work all year |
| Overtime handled wrong | Full OT wages counted instead of straight-time | Track OT separately in payroll |
| Office not split out | Clerical wages charged at a field rate | Keep office payroll in clerical (8810) |
This is the biggest single cause of a bad audit. If a subcontractor or 1099 laborer can't produce a valid workers' comp certificate, the carrier treats what you paid them as your payroll and charges premium on it — frequently at your highest field rate. Pay an uninsured sub $80,000 and you can be billed as though that $80,000 were your own high-rate wages. The defense costs nothing: collect a current certificate of insurance from every sub and contract laborer before they start, keep it on file, and make sure it's still valid during the policy period. This is the same discipline that protects contractors on the job — see our guides on contractor workers' comp cost and lowering your experience mod.
If the audit is wrong, you can request a revision — but there are deadlines, so move promptly. Valid grounds commonly include:
Gather the supporting documents — a corrected class-code breakdown, the missing certificates, payroll detail, and the state tax filings that back it up — and submit the dispute in writing before the carrier's deadline. An independent agent can review the audit worksheet line by line with you and push the correction through the carrier, which is usually faster and more successful than fighting it alone.
Say a small landscaping company estimated $300,000 in payroll but actually paid $360,000, including $50,000 to a mowing sub with no certificate on file and $40,000 to a bookkeeper who was never split into clerical. At audit, the carrier bills the extra $60,000 of real payroll, adds the $50,000 sub payroll at the field rate, and charges the $40,000 of office wages at the field rate too, because it wasn't split out. Three preventable issues stack into a five-figure surprise. Had the sub's certificate been on file and the bookkeeper coded as clerical, only the genuine $60,000 of extra field payroll would have been billed.
Bettr Coverage is an independent commercial insurance agency serving Georgia and the Southeast. We help owners get ahead of the audit — organizing class-code splits, subcontractor certificates, and payroll records so the true-up is accurate the first time — and we review completed audit worksheets to catch misclassified payroll, uncredited certificates, and overtime errors that inflate the bill. When an audit is wrong, we work the correction through the carrier, and we structure the program up front with realistic estimates and pay-as-you-go options so there are fewer surprises at year-end. One agency, one relationship, the whole program reviewed together — and when a job calls for a bond we coordinate it through our sister brand BettrBonds.
Bettr Coverage reviews your audit worksheet, checks the class-code splits and subcontractor credits, and pushes corrections through the carrier — and sets your program up so next year's true-up is honest.
Get a free coverage reviewThe carrier's year-end true-up. Premium was estimated on projected payroll; the audit checks it against actual payroll and bills the difference or refunds it. It's standard on almost every policy.
Payroll records, quarterly 941s and state unemployment reports, W-2 totals, payroll broken down by type of work, overtime and 1099 totals, and — most important — certificates of insurance for every subcontractor.
Usually uninsured subs or 1099s added to your payroll, payroll higher than the estimate, or misclassified work. Subcontractor documentation and class-code errors cause most of them.
Yes. Valid grounds include payroll that should have been split into a lower code, overtime not reduced to straight-time, uncredited sub certificates, and arithmetic errors. Submit corrections in writing before the deadline.
If a sub can't show a valid comp certificate, the carrier charges you premium on what you paid them, often at your top rate. Collect and file every sub's certificate before they start.
We prepare you before the audit, review the worksheet to catch inflated charges, push corrections through the carrier, and set the program up with realistic estimates and pay-as-you-go so the true-up is honest.
For general information only. Not a quote or contract of insurance. Audit procedures, overtime treatment, and class-code rules vary by carrier, state, and current filings, and change over time. Confirm the specifics of your audit with your carrier or a licensed agent. Coverage subject to policy terms and carrier appetite.