Workers' comp class codes for home service trades

What a class code actually is

Workers' compensation insurers group businesses by the kind of work their employees do. Each group has a classification code and a rate, usually expressed per $100 of payroll. The rate reflects how often workers in that classification get hurt and how expensive those injuries tend to be. Roofing carries a far higher rate than office clerical work because falls are common and severe: OSHA reports that falls to a lower level caused 389 of 1,034 construction deaths in 2024^[3].

Most states use classifications from the National Council on Compensation Insurance (NCCI). Some states, including California, New York and Pennsylvania, run their own rating bureaus with their own codes, and a few states, such as Ohio, Washington, North Dakota and Wyoming, sell comp only through a state fund. If you work in more than one state, expect different codes and rules in each.

This article explains the mechanics so you can ask better questions. Your agent and carrier assign the actual codes; check them with a specialist if anything looks off.

How the premium is calculated

Strip away the forms and the premium follows one formula:

Because payroll is the base, high-wage trades generate more premium per worker even at the same rate. Census data shows how much payroll per employee differs across home services:

In 2023, electrical contractors paid an average of $76,545 per employee^[1] and plumbing and HVAC contractors $73,693^[4], against $70,552 at roofing contractors^[5], $53,466 at pest control companies^[6], $51,286 at landscapers^[7] and $30,089 at janitorial and maid services^[2]. Multiply those payrolls by very different rates and the comp line on your P&L varies enormously by trade.

Comp is part of a bigger benefits bill. Benefits made up 30.0% of private employer compensation costs in June 2026^[8], and legally required benefits such as comp, unemployment insurance and payroll taxes are a meaningful share of that.

Worked example: one company, three codes

Example. The numbers below are fictional and only show the mechanics. Real rates vary by state and carrier.

In this example, with an experience mod of 0.90, the modified premium is about $45,000. With a mod of 1.20, it is about $60,000. Same payroll, same rates, a $15,000 swing based on claim history. Now imagine the carrier puts the two comfort advisors under the HVAC code because their duties are not documented: their payroll would cost about $6,150 instead of $600.

Where misclassification usually happens

• Office staff who also ride along or help in the field. If someone does field work, many rules require their payroll to go into the field class unless the duties are clearly separated and recorded.
• Sales staff with field duties. Comfort advisors who never touch tools may qualify for an outside sales code; ones who help install usually do not.
• Mixed trades. A handyman company doing carpentry, light electrical and gutter work, or an HVAC company that also does roofing on condensers, may need several codes. Some states let you split payroll by job type only if your records show hours by type.
• Owners and officers. Rules for including or excluding owners vary by state and entity type. Decide deliberately and file the right forms.
• Uninsured subcontractors. If a sub has no comp policy, the auditor will often count what you paid them as your payroll, at your field rate.

Misclassification can go both ways. Codes that are too low look cheap until the audit, then produce a back-premium bill. Codes that are too high quietly overcharge you every year. Ask for a classification review whenever your work mix changes.

Preparing for the payroll audit

Your policy premium starts as an estimate. After the policy year, the carrier audits your actual payroll and recalculates. A smooth audit takes about an hour of preparation if your records are in order:

1. 01

   Pull payroll reports

   Quarterly federal payroll filings (Form 941), state unemployment reports and a payroll register by employee for the policy period.

2. 02

   Split by class

   Show payroll by employee and by class code, with job titles and short duty descriptions. Many states exclude the overtime premium portion of pay, so have it shown separately.

3. 03

   List subcontractors

   Every sub you paid, the amount, and a certificate of insurance showing active comp coverage for the dates worked.

4. 04

   Document exclusions

   Owner exclusion forms, if any, and records for anything you believe should not be in payroll.

5. 05

   Review the draft

   Ask for the auditor's worksheet before it is final and question anything that moved payroll into a higher class.

Trade by trade: what to watch

• HVAC and plumbing: service, installation and duct fabrication can carry different codes in some states. If you fabricate in a shop, ask whether shop payroll belongs in its own class.
• Electrical: residential service and low-voltage work such as alarms or data cabling may be classified differently. Track hours by type if you do both.
• Roofing: usually among the most expensive classifications in home services. Gutter, siding and repair-only work may be rated differently, but only if your records show the split.
• Cleaning: residential maid service and commercial janitorial work may sit in different classes. Window cleaning above a certain height is often separate.
• Landscaping and lawn care: mowing, tree trimming and pesticide application can each be rated differently. Tree work at height is typically far more expensive.
• Garage doors and handyman: installation of doors and openers is often grouped with carpentry; a handyman doing many trades should expect the carrier to look closely at the mix.

Codes and their wording change, so treat this list as prompts for a conversation with your agent rather than as the rules themselves.

Subcontractors and 1099 workers

Comp audits treat subcontractors very differently depending on paperwork. If a sub has its own active comp policy and you have the certificate on file, their payments usually stay off your premium. If not, the auditor may treat what you paid them as your payroll, often in your highest field class.

The same risk applies when workers are labeled as independent contractors but work like employees: your schedule, your trucks, your tools, your customers. State labor agencies and comp carriers each apply their own tests, and an injured "contractor" may end up claiming against your policy anyway. Collect certificates before the first job, set a calendar reminder for every expiry date and stop work orders when coverage lapses.

How claims shape your mod

The experience modification compares your actual losses with the losses expected for a business of your size in your classes. A mod of 1.00 is average; below 1.00 lowers your premium, above raises it. Most rating formulas weigh the number of claims more heavily than their size, so many small claims can hurt more than you expect.

Practical levers that bring the mod down over time:

1. Prevent injuries in the first place: ladder rules, lifting help for heavy equipment, driver safety and heat illness plans.
2. Report injuries to the carrier quickly. Late reports tend to cost more.
3. Offer modified duty so injured techs can return sooner in a shop, warehouse or ride-along role.
4. Review loss runs every quarter with your agent and close out stale reserves.

Our guides on ladder safety and driver safety and MVR checks cover two of the biggest sources of claims in field service.

Questions to ask your agent at renewal

• Which class codes are on my policy, and what operations does each one describe?
• Is any clerical or outside sales payroll eligible for a lower code, and what records do you need?
• What is my current mod, what claims drive it, and when will each claim drop out of the calculation?
• Which safety programs or credits does the carrier recognize?
• Would a pay-as-you-go comp policy tied to payroll reduce audit surprises?