How to Prepare for a Workers’ Comp Premium Audit: A Contractor’s Checklist (2026)
7 min read · Updated June 7, 2026
An auditor checks four things: your payroll, your subcontractors, your owner/officer payroll, and whether your people are classified correctly. Prepare those four and you’ll avoid the two bad outcomes — a surprise bill, or quietly overpaying because you didn’t push back.
1. Subcontractors (where most of the money is)
- A current certificate of insurance with a workers’ comp line for every sub.
- Dates that cover the entire period each sub worked — check for mid-job lapses.
- 1099s and contracts that support “these were real subs, not employees.”
If a sub can’t be documented, their pay gets reclassified as your payroll at your class rate. Run your subs through the COI Gap Checker first.
2. Payroll records
- Payroll journal/summary, plus 941s, W-2/W-3, and state unemployment filings to reconcile against.
- Wages broken out so the auditor can see regular vs overtime.
3. Don’t overpay on overtime
In most states, only the straight-time portion of overtime counts toward premium — the extra “half” in time-and-a-half is excluded. A quick way to find the excludable amount: divide total overtime pay by 3. If your records don’t separate overtime, you can get charged on the full amount. (A handful of states — PA, DE, UT, NV — include full overtime, so confirm yours.)
4. Owner / officer payroll
Owners and officers can often be capped at a state minimum/maximum or excluded entirely. Auditors sometimes drop the full owner salary into the governing class by default. Know your state’s cap and check the number.
5. Classification
Auditors compare what people actually did to how they’re classified. Someone coded “clerical” who’s regularly on a jobsite gets bumped to a higher-rated class. A written job description with time breakdowns is what wins a classification dispute — a verbal explanation won’t. More on class-code overcharges →
Stay audit-ready all year, not the week before
The contractors who don’t get surprised treat readiness as a monthly habit: collect COIs up front, re-check on expiration, keep class duties documented. That’s the workflow we’re building into a tool that hands you an audit-ready binder on demand. Get early access →
Frequently asked questions
How do I prepare for a workers’ comp premium audit?
Have payroll records and tax filings ready, a COI or exemption for every subcontractor, overtime separated out, and owner/officer payroll and classifications documented.
What documents does a workers’ comp auditor want?
Your payroll journal, 941s, W-2/W-3 and state filings, subcontractor COIs and 1099s, and records that separate overtime and owner pay.
What’s the most important thing to prepare for an audit?
Subcontractor coverage — it’s where most surprise bills come from. Make sure every sub has a documented workers’ comp line or exemption for the dates they worked.
See your own exposure — free
Two free tools, no signup: estimate your audit surprise, and check whether your subs’ COIs actually protect you.
Related guides
What Is a Workers’ Comp Premium Audit? A Contractor’s Plain-English Guide
Just got an audit notice? Here’s what a workers’ comp premium audit is, why it happens every year, what the auditor checks, and how to come out even instead of owing thousands.
6 min read · Read →Underreporting Payroll to Lower Workers’ Comp: Why It Backfires
Shaving payroll or miscoding workers to cut premium is premium fraud — and the audit is built to catch it. Here’s how it’s detected and what it costs.
5 min read · Read →Workers’ Comp Deposit Premium: What That Upfront Payment Is
The chunk you pay when a workers’ comp policy starts is the deposit premium. Here’s what it is, whether you get it back, and how to keep it from being inflated.
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