Insurance Considerations When Hiring Your First Plumbing Employee

The short version

For a one-person plumbing shop, the first hire is the biggest insurance event in the life of the business, bigger than the first van or the first commercial contract. Until that day, a C-36 licensee with no employees can keep a workers' compensation exemption on file with CSLB. The hire ends that. California Labor Code section 3700 requires every employer with one or more employees to carry workers' compensation, and CSLB's rule is that the exemption becomes invalid the moment you hire anyone subject to that law. From the first hour the helper works, you are an employer, and if you have no policy, an uninsured one.

The workers' compensation policy is the urgent piece, but it is not the only one. The new employee's payroll has to be classified correctly or the first audit will reprice the policy. They will drive a van, which means the auto policy needs to know about them. They will do work under your license and your name, which increases the general liability exposure you had alone. And outside insurance entirely, the hire triggers employer registrations and payroll obligations that have their own deadlines. This article walks through each, in the order to handle them, and ends with a checklist.

A realistic scenario

This is a hypothetical. A sole-operator plumber in the Inland Empire has run service and repair work under her own C-36 for five years with an exemption on file. Her schedule is full and she hires a former apprentice she knows, at $27 an hour, to start the following Monday. She plans to call her broker that week; she has a general liability policy and a commercial auto policy on her one van, and assumes the workers' compensation can be added the same way.

On Thursday of the second week, the new hire is carrying a water heater down exterior stairs, loses his footing and fractures his wrist. He goes to urgent care, where the intake form asks for the employer's workers' compensation carrier.

The policy was quoted on Tuesday but not yet bound; the broker was waiting for a signed application. There is no coverage for the injury. The plumber owes the medical bills and the employee's lost wages directly, and the employee can sue her civilly. If the matter reaches the Division of Labor Standards Enforcement, she faces a stop order and the penalties in Labor Code section 3700.5 — a misdemeanor, a fine of not less than $10,000 and up to a year in county jail — plus a civil penalty of the greater of twice the premium she should have paid or $1,500 per employee. If the claim reaches the Workers' Compensation Appeals Board, an assessment of $10,000 per employee on payroll for a compensable injury applies, up to $100,000. And when CSLB learns an exempt licensee had an employee, the license is subject to suspension, which puts every job she is working on at risk.

Two weeks of payroll. The policy would have been in force on Monday if she had called the Thursday before the offer.

Day one: the exemption ends and workers' compensation must be in force

What the law requires

Labor Code section 3700 is unconditional: an employer with one or more employees must carry workers' compensation insurance. CSLB enforces it at the license level. A licensee must have a certificate of workers' compensation insurance on file with CSLB listed as the certificate holder, or a signed exemption certifying that the licensee has no employees. C-36 plumbing is not one of the five classifications (C-8, C-20, C-22, C-39 and C-61/D-49) that must carry coverage regardless of staffing, so a true sole operator may use the exemption today. The moment you hire, the exemption is invalid.

The 90 days

CSLB must receive proof of coverage within 90 days of the hire. Read that as a filing deadline, not a grace period. Under the Labor Code you are an uninsured employer from the first day of the hire until a policy is in force; the 90 days describes how long CSLB gives you to get the paperwork onto your license record, not how long you may operate without a policy. Failure to maintain required coverage results in license suspension, and work performed while suspended is treated as unlicensed, which in California can mean you cannot enforce payment for it.

Sequence: bind the policy before the employee's first day; send the certificate to CSLB; confirm the license record shows the policy. Then let them start.

Who counts as an employee

California law decides, not what you call the arrangement. A helper paid by check or cash, a "1099 plumber" who works under your direction with your tools on your schedule, a family member on the payroll, and the workers of an unlicensed subcontractor (generally treated as your employees under Labor Code section 2750.5) all count. If you are hiring someone to do plumbing work and you control how they do it, plan on them being an employee for workers' compensation purposes and buy the policy. See workers' compensation insurance for California plumbing companies for how the policy works once you have it.

Classifying the new hire's payroll

Workers' compensation premium is calculated on payroll by classification, and the first hire is where the classification is set. Get it right at inception, because the audit will apply the correct code regardless of what the application said.

Plumbing field payroll in California is assigned to a dual-wage classification pair, 5183 and 5187. The split is by the employee's regular hourly wage against a threshold set by the WCIRB that applies by policy effective date: $32 per hour for policies effective September 1, 2024 through August 31, 2026, and $35 per hour for policies effective on or after September 1, 2026. An employee paid at or above the threshold goes in the higher-wage, lower-rated classification; an employee paid below it, like the $27-an-hour apprentice in our scenario, goes in the lower-wage, higher-rated classification. The wage must be verifiable from original time records showing daily hours and start and end times (or a collective bargaining agreement); payroll that cannot be verified is assigned to the lower-wage classification at audit.

If the first hire is an office person who does no plumbing work, the clerical classification 8810 may apply, and 8742 for an outside salesperson. The duties must fit the classification's rules and the payroll records must support it. A "dispatcher" who also rides along and hands tools is plumbing payroll. See workers' compensation payroll classifications for plumbing contractors.

Tell the broker the hire's duties, hourly wage and expected hours. A policy written on a guess is repriced at the first audit; see how to prepare for a workers' compensation premium audit.

The X-Mod comes later

A new employer is not experience rated until expected losses over the experience period reach the WCIRB's eligibility threshold, which is $11,700 for experience ratings effective on or after September 1, 2026 and is adjusted each year. With one employee you will likely be below it for a while, which means your premium is the manual rate without a modification. Claims you have now still count when you become eligible, because the experience period reaches back three years. See what is an X-Mod and why does it matter.

Employers' liability

A workers' compensation policy has two parts. Part One pays the benefits the Labor Code requires, without regard to fault. Part Two, employers' liability, covers you for lawsuits related to an employee's injury that fall outside the no-fault benefit system, subject to the policy's terms. It has an important limit for contractors: the standard form generally excludes liability you assumed under a contract. So in a third-party-over action, in which an injured employee sues the general contractor and the GC then demands that you indemnify it under the subcontract, the indemnity demand is usually a general liability question (the "insured contract" coverage), not an employers' liability one. Part Two carries its own limits, and general contractors' subcontract insurance requirements often specify them. Ask what limits are on the quote, compare them with any contract you sign, and ask whether higher limits are available.

Commercial auto: a second driver

If the new employee will drive a company van, even occasionally, they need to be a listed driver on the commercial auto policy before they do. Carriers rate on drivers and will run motor vehicle records; an employee with a poor record may be excluded, which you want to know before you hand over keys. If the employee will ever drive their own vehicle for work — a supply house run in their own truck — confirm that hired and non-owned auto liability is on the policy. It covers your company's liability when a vehicle you do not own is used in your business; it does not cover the employee's vehicle itself. See commercial auto insurance for plumbing service fleets.

If the van is still on a personal auto policy because it was your personal truck first, the first hire is the moment to move it. A personal auto policy is not written for a business vehicle driven by an employee, and depending on its terms the carrier may dispute or deny a claim that arises from that use.

General liability: more exposure, same policy

Your general liability policy does not change its structure when you hire, but the exposure it covers does. Two people doing work under your name produce more completed operations, more jobsites and more opportunities for property damage, and the policy's premium basis, usually payroll or receipts, will reflect that at audit. Tell the carrier you now have an employee, confirm the payroll basis, and read the policy for any exclusion that bears on employees: injury to your own employees is a workers' compensation matter and is excluded from general liability, except that the standard form gives back coverage for liability you assumed under an "insured contract", such as a typical subcontract indemnity clause. Some policies carry action-over or contractual liability limitation endorsements that remove that coverage for the GC-sues-you scenario described above, so ask whether yours does. See general liability vs workers' compensation for plumbers for where the line falls.

Tools and equipment coverage is unchanged by the hire, except that a second person now has access to them; make sure the equipment schedule reflects what rides in the van each day.

Obligations outside insurance

The hire also makes you an employer for tax and labor purposes. Treat these as a list for your payroll provider or accountant rather than something to do from memory; each has its own deadline and penalty. Generally they include registering as an employer with the California Employment Development Department within 15 days of paying more than $100 in wages in a calendar quarter, federal employer identification and withholding, new-hire reporting, required workplace postings, wage statements, and the written notices California requires at hire. Two of those notices tie directly to insurance. The Labor Code section 2810.5 notice to employee, due at the time of hire, must state the name, address and phone number of your workers' compensation carrier, so the policy has to exist before you can complete it. And every new hire must receive a written notice of workers' compensation rights; DWC publishes a time-of-hire pamphlet for this, and carriers commonly provide it along with the required workplace poster.

The 2028 change

Under SB 216, as amended by SB 1455 (2024), the exemption option for licensed contractors with no employees ends on January 1, 2028; after that date, under current law, every licensee must carry workers' compensation regardless of staffing. If you have hired, this does not change your situation; you already must carry coverage. It matters if your employee leaves and you consider going back to an exemption, because that door closes in 2028. Legislative dates can move; check CSLB's workers' compensation page before relying on either date.

A first-hire checklist

In order:

1. Before the offer: call your broker. Give the hire's duties, hourly wage, start date and expected annual payroll. Ask for the workers' compensation quote, the employers' liability limits, and whether the general liability and auto policies need endorsement.
2. Before the start date: bind the workers' compensation policy. Confirm the effective date is on or before day one. Add the employee as a listed driver on the auto policy; confirm hired and non-owned coverage.
3. Day one: have the workers' compensation notice to employees, the claim form and the carrier's reporting instructions available. Start time records that show hourly wage and hours.
4. Within the first week: send the certificate to CSLB with CSLB as certificate holder; confirm the license record updates. Complete the EDD and payroll registrations with your payroll provider.
5. Within the first month: notify the general liability carrier of the employee; review the equipment schedule; file the policy and the CSLB confirmation where you can find them.
6. Ongoing: keep payroll and time records in a form that survives an audit; calendar the policy renewal and plan a renewal review 90 days out.

Practical takeaway

The rule is simple to state and easy to get wrong under schedule pressure: the policy goes in force before the employee does. Make the broker call the first step of hiring, before the offer. Give accurate duties and wage information so the classification is right from the start. Get the certificate to CSLB and confirm the record. Add the driver, confirm hired and non-owned, tell the general liability carrier, and set up the employer registrations with someone who does them for a living.

The Inland Empire plumber in our scenario would have had a bound policy on the Monday her apprentice started, a classified payroll line that matched his $27 wage, and a workers' compensation claim for a broken wrist instead of a personal liability and a license problem. If a first hire is in your near future, start a quote now; it saves as you go, and a licensed Pembroke producer will walk through the timing with you.