Why most U.S. employers overpay workers’ comp, and why nobody catches it

How premium is calculated, where the errors come from, and what the appeal process actually looks like7 min read

U.S. employers pay roughly $55 billion in workers’ compensation premium each year, making it one of the largest commercial property and casualty insurance lines in the country.[1] A meaningful share of that is overcharged through mechanical errors at audit. The reasons are structural, not sinister, but the result is the same. Mid-size employers routinely lose $20,000 to $150,000 a year on a single policy.

This post walks through how premium is actually calculated, where the errors come from, why nobody fixes them, and what to do if you suspect you are on the wrong end of one.

How premium is calculated

Two numbers determine your annual workers’ comp premium. The first is your payroll, broken out by employee role. The second is the rate your state’s rating bureau assigns to each role, expressed as dollars per hundred of payroll.

Suppose you run a small construction firm in North Carolina. You have ten field carpenters earning $52,000 each, two estimators earning $68,000 each, and a controller earning $95,000. The state’s rate for carpenters (NCCI class 5403) is around $7.40 per $100. For clerical office staff (class 8810) it is roughly $0.16.[2] The math:

Now suppose at audit, the carrier reclassifies the two estimators as “carpenters” instead of “office.” The same payroll math becomes:

A single class code change moved two employees and added 25 percent to the annual premium. The mistake sits on one line of an audit worksheet that almost nobody reads line by line.

That is one error. Most employers have several at once.

Where the errors come from

Five recurring errors account for the bulk of what we see at audit.

1. Office staff swept into the field class at policy bind

Receptionists, estimators, project coordinators, and bookkeepers get bound and then audited under the operative class because the carrier never asked, or because the agent filled out the application using the company’s primary industry code without breaking out roles.

2. Construction wage cap not applied

Construction payroll is not always billed on every dollar an employee earns. Some states apply a weekly payroll cap to eligible construction classifications before the field rate is applied. The cap amount changes by state and policy year, but the audit logic is the same: payroll above the cap should be removed from the high-rate construction basis. When this rule is missed, high-earning field employees can be billed on payroll that should have been excluded.

3. Overtime premium not excluded from the basis

Workers’ comp premium is supposed to be charged on regular wages, not the extra premium portion of properly identified overtime. If an employee earns time-and-a-half, the regular 1.0× wage stays in the premium basis, but the extra 0.5× overtime premium should be removed. When payroll is audited at the full 1.5× amount, the employer pays premium on wages that should not have been included.

4. Officer cap missed

Every state caps officer payroll at a weekly maximum for premium purposes. In Texas it is $1,200 a week ($62,400 a year). In California it is $3,175 a week ($165,100 a year, effective Sept 2025).[3] Wages above the cap are not chargeable. A founder making $325,000 a year in Texas should be charged on $62,400 of payroll, not $325,000. Carriers routinely charge the full salary unless the policyholder asks otherwise. The cap exists to prevent the carrier from charging open-ended officer comp at the full operative rate.

5. Outside salespeople buried in the company’s primary class

Outside sales reps qualify for NCCI class 8742, which carries a much lower rate than most industry classes. Carriers default to the company’s primary class.

These errors compound. A mid-size construction firm with field staff, a back office, two founders earning above cap, and a small sales team can have all five at once.

Why nobody catches them

There are three reasons, and they are structural rather than negligent.

The carrier has no incentive to. Premium audits are run by the carrier or a third-party auditor working on the carrier’s behalf. The auditor’s job is to confirm reportable payroll, not to second-guess the classification structure that determined your rate. A carrier that finds it overcharged a policyholder would have to refund the money. Few do.

The broker cannot. Brokers are paid commission on premium. A broker that helps you cut premium cuts their own income. Even brokers who would happily file an appeal on a client’s behalf often have a clear conflict of interest, and many carriers restrict producers from filing on the carrier’s appeals docket directly. Brokers also tend to handle a wide book and rarely have the manual-rule fluency to spot a wage-cap miscalculation in the audit worksheet.

The audit worksheet is built to be skimmed, not audited. A typical mid-size finance team oversees ten or fifteen insurance lines. Workers’ comp is one. The audit worksheet runs forty to a hundred pages and uses terminology that is opaque outside the workers’ comp specialty. The bottom-line premium change is the only number most readers ever look at, and the line-item errors that produced it sit underneath, unreviewed.

The result is that errors go uncorrected for years, and quietly compound across renewal cycles.

How the appeal process actually works

Here is the part most employers do not realize. The workers’ comp appeal process is routine, well-documented, and explicitly designed for exactly this situation.

The procedure varies by state but the mechanics are similar everywhere. In plain steps:

1. Identify the misclassification, with rule citations.
2. File a written appeal package with the carrier. Include the cited rule, supporting payroll documentation, and signed duties affidavits from the employees in question.
3. Carrier responds within 60 days (NCCI states) or 90 days (New York).
4. If approved, the carrier issues a credit endorsement on the current policy or a refund check for closed policy years.

Carriers do not retaliate. They do not cancel policies over appeals. The procedure is part of normal rating bureau operation. Filed appeals succeed roughly 60 to 70 percent of the time when the rule citation and duties documentation are clean.

What we do

WC Audit Recovery is this audit process, automated. We take your declarations page and a payroll register, run them through an engine that checks the five recurring errors plus state-specific cap rules, and produce a per-employee, per-rule recoverability report.

If we find recoverable premium, we file the appeal package with your carrier on your behalf. The cover letter cites the specific rule and the relevant rating bureau’s appeal procedure. Duties affidavits are pre-filled and ready for HR signoff. The premium recalculation worksheet shows the dollar math for every employee in question.

You only pay if we get you money back. The assessment and audit are free. We take 50% of what your carrier refunds. If there’s nothing to recover, you owe nothing.

What it costs to ignore this

The math at the population level:

• Average mid-size employer (50 to 500 employees, $5M to $80M revenue): annual workers’ comp premium of $25,000 to $200,000.
• Recovery probability across the five recurring errors: roughly 45 percent.
• Average recovery when found: 5 to 15 percent of annual premium.
• Retroactive window: three years in most NCCI states.

An employer with $100,000 in annual workers’ comp premium has a roughly 45 percent chance of leaving $15,000 to $45,000 unrecovered across three years. The cost of finding out is zero.

What to do next

If you suspect your policy may be miscalculated, send us your most recent WC declarations page and a recent payroll register. We will run the audit and respond within 48 hours.

The form on the home page takes two minutes. We will tell you in writing whether there is meaningful recovery on your policy. If there is not, we will tell you that too.

Sources

1. NAIC 2024 Market Share Reports for Property & Casualty Groups (published 2025). U.S. workers’ compensation direct written premium of $55.42 billion in 2024. agencychecklists.com summary ↩
2. NCCI loss-cost filings (state-specific). Class code rates cited (5403 ~ $7.40, 8810 ~ $0.16) are illustrative North Carolina loss costs from the NCCI 2025 filing; rates vary by state and year. Always confirm against your state’s current published filing. ncci.com / state filings ↩
3. State-specific officer-payroll caps. Texas: officer/LLC member maximum payroll is $62,400 a year ($1,200 a week) per TDI rules. California: executive officer maximum remuneration is $165,100 a year ($3,175 a week) effective Sept 1, 2025 per WCIRB. Caps adjust annually; verify against your state’s current filing. tdi.texas.gov · wcirb.com ↩