How to Verify a California Plumber's Insurance: Bond, Workers' Comp and Liability
Almost every homeowner asks the same question before a big plumbing job — "are you licensed, bonded and insured?" — and almost every contractor says yes. But those three words describe three different things, only one of which the state verifies, and none of which means your house is covered if a repipe floods your walls or a technician gets hurt in your crawlspace.
What follows is general information, not legal advice. The underlying rules are all public, and you can check them yourself in about ten minutes.
The $25,000 bond is not insurance for your house
Every active California contractor must post a contractor license bond. Since January 1, 2023 the amount has been $25,000 (it was $15,000 before), set by Business and Professions Code section 7071.6. In CSLB's own words, the bond is "filed for the benefit of consumers who may be damaged as a result of defective construction or other license law violations, and for the benefit of employees who have not been paid wages."
That is narrower than it sounds. A bond is a promise by a surety company, not a policy that pays on your loss: it targets defective work and license-law violations, not accidental property damage generally and not anyone's injury. And $25,000 is a fixed sum — it does not scale with what happened to your home. A whole-house repipe or a sewer replacement can approach that figure on its own, before drywall and flooring; our repiping cost guide and sewer line repair pricing give the ranges.
Claiming is a process, not a payout button: identify the surety listed on the license, gather your contract and payment records, contact the surety. Disputes within the small claims limit — currently $12,500 for an individual — can go to small claims court; above that, superior court. If the license was later revoked, you generally still have two years from its original expiration date to act (section 7071.11). A bond claim and a CSLB complaint are separate tracks — our guide to filing a complaint against a plumber in California covers the regulatory side.
Workers' comp: what the license actually proves right now
Here the advice repeated all over the web is currently wrong, and the correction matters to you.
California contractors must either show CSLB proof of workers' compensation coverage or file a signed exemption certifying they have no employees. A few classifications must carry coverage whether or not they employ anyone: C-8 Concrete, C-20 Warm-Air Heating/Ventilating/Air-Conditioning, C-22 Asbestos Abatement, C-39 Roofing, and C-61/D-49 Tree Service. C-36, the plumbing classification, is not on that list. A one-person plumbing contractor can legally hold an active C-36 license today with no workers' comp policy at all.
Senate Bill 216 was meant to end that, making coverage universal on January 1, 2026 — the date most articles still cite. It didn't happen. Senate Bill 1455, signed September 22, 2024, moved it: the bill text now reads "This section shall become operative on January 1, 2028," and requires CSLB to build a process for verifying no-employee exemptions by January 1, 2027. Until then, a plumber with an exemption on file is fully compliant — so don't read "active license" as "carries workers' comp."
Two things still help. An exemption dies the moment the contractor hires someone (proof must reach CSLB within 90 days of the hire), and a licensee who lets required coverage lapse gets suspended, which a lookup shows. That gap between what a license certifies and what it doesn't is the same one we draw in our guide to certified versus licensed plumbers in California.
General liability: CSLB does not require it for most plumbers
General liability is the coverage that would respond if a plumber's work damages your property — the supply line that lets go during a pressure test, the torch that scorches a joist. CSLB does not require it for licensure. The one clear exception: contractors licensed as limited liability companies must carry cumulative liability insurance of at least $1,000,000 for five or fewer listed members, plus $100,000 per additional member up to a $5,000,000 cap (Business and Professions Code section 7071.19), plus a separate $100,000 employee/worker bond.
For every other business structure it is voluntary. Which is exactly why CSLB tells consumers to "ask to see a copy of the Certificate of Insurance or ask for the name of the contractor's insurance carrier and agency." The board is telling you to do the verification it doesn't do for you.
The four-step check
- 1. Pull the license detail page. Look up the number at cslb.ca.gov and confirm the status is active, the classification includes C-36, and the business name matches your estimate exactly. The detail page has separate Bond and Workers' Compensation sections — read both, not just the status line. Our CSLB license check guide walks the lookup screen field by field.
- 2. Read what the workers' comp section says. It will show either a policy with a carrier and expiration date, or an exemption on file. Both can be legitimate. An exemption simply tells you no employees are covered — so ask directly who will be on your property, and whether anyone besides the license holder will be working.
- 3. Request a certificate of insurance naming you. Ask for the certificate to be issued with your name and job address in the certificate holder box. Contractors do this routinely and it costs them nothing. A generic PDF with no holder named, or one whose dates have passed, is not a verification.
- 4. Call the agency printed on the certificate. Confirm the agency's number against a public listing first, then ask one question: is this policy in force today for this named insured? Certificates are snapshots and policies get cancelled for non-payment, so this is the only step that catches a dead policy — and the step almost nobody takes.
If a contractor stalls, sends a certificate in a different business name, or tells you the license "covers" insurance, treat it as the warning sign it is — our guide to plumber red flags and scams covers the rest of the pattern. Emergency calls are the hardest place to hold this line; see emergency plumbing costs.
What you are exposed to if you skip it
The first exposure is property damage with nobody behind it. If an uninsured contractor floods your house, your recourse is the contractor's assets, the bond to the extent the loss fits what a bond covers, and litigation — while the secondary damage compounds. Our guides to who pays for mold remediation after a plumbing leak and how long plumbing work is warrantied in California cover where that leads. If the contractor's suppliers go unpaid, you can also face a mechanics lien on a job you already paid for.
The second is an injured worker, and homeowners consistently underestimate it. Labor Code section 2750.5 creates a rebuttable presumption that someone performing work requiring a contractor's license is an employee, not an independent contractor — holding a valid license is a condition of independent-contractor status. Hire an unlicensed person for licensed plumbing work, and if they are hurt, the presumption runs toward you being the employer.
People assume their homeowners policy absorbs that. It only partly can. Insurance Code section 11590 has required since 1977 that comprehensive personal liability policies issued or renewed in California carry workers' comp coverage for persons defined as employees by Labor Code section 3351 subdivision (d) — "residential employees," whose duties are incidental to the ownership, maintenance or use of the dwelling and outside the owner's own trade or business. Section 3352(h) then carves out anyone in that category who worked fewer than 52 hours in the 90 days before the injury, or earned under $100 from that employer in that window. A short plumbing job can land squarely in that gap, and whether a plumbing contractor fits the residential-employee definition at all is a fact question decided case by case. Don't assume — ask your own insurer how your policy responds before you hire someone whose coverage you haven't verified.
Why the invisible risk is bigger than it looks
Uninsured work is common in this trade because most of the industry is very small firms — and injuries in very small firms are systematically undercounted. A 2011 study in the American Journal of Industrial Medicine by Dong, Fujimoto, Ringen and colleagues cross-checked fifteen years of data across five national datasets and found the federal injury survey captured only about 25% of severe injuries among Hispanic workers and about 60% among white workers in small construction establishments (DOI 10.1002/ajim.20928). The injuries happen; the paperwork often doesn't.
What that means for whoever ends up paying appears in a 2008 study in the same journal by Nicholson, Bunn and Costich: among work-related emergency-department visits at one academic health center, 20% of self-declared work injuries came with no reported workers' comp coverage, construction workers were over-represented in that group, and 92% of them also lacked health insurance (DOI 10.1002/ajim.20565). It's an exploratory single-center study, not a national estimate — but it describes the mechanism exactly: when there is no policy, the medical bill doesn't disappear. It goes looking for someone.
Ten minutes of verification is the cheapest part of any plumbing project. Describe your job and request a free quote.
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