License classes in California
| Class | Scope |
|---|---|
| C-36 Plumbing Contractor | Provides a supply of safe water, ample in volume and of suitable temperature, and the proper disposal of fluid waste from the premises; covers waste disposal and on-site systems, piping and storage and venting for gases and liquids including vacuum, compressed air and medical, dental and industrial gases, flues and connections for space-heating gas appliances other than forced warm air, water and gas piping from the meter to the structure, water heating equipment including solar, and repair or replacement of valves, backflow preventers and regulators. |
How to verify a contractor before work starts
- Ask for the license number and the exact registered name it is held under.
- Check that name against the company on the estimate, the invoice and the vehicle.
- Check the status is current, not expired, suspended or revoked.
- Ask for a certificate of insurance issued to your address, not a policy number read out on a call.
- For gas, sewer, water-heater or repiping work, ask which permit is being pulled and by whom.
Which plumbing code applies
2025 California Plumbing Code, Title 24 Part 5, based on the 2024 Uniform Plumbing Code (IAPMO), effective January 1, 2026 The 2025 California Plumbing Code, Title 24 Part 5, is based on the 2024 Uniform Plumbing Code; it was published on 1 July 2025 and took effect on 1 January 2026 under California's triennial code cycle. Cities and counties adopt the state code and may amend it by local ordinance, so local amendments have to be checked alongside the state edition.
Permits
Permits are issued by the local building department, and CSLB's guidance on home improvement contracts is explicit that the contract should state who is responsible for obtaining them - normally the contractor, so a request that the homeowner pull the permit instead is worth questioning.
Complaints
CSLB's Check a License service shows whether a contractor's license is active and which classifications it carries, and CSLB is the state body that takes consumer complaints about both licensed and unlicensed contractors.
PlumberCalifornia is not a licensed contractor
PlumberCalifornia is an independently operated referral service. PlumberCalifornia is not a plumbing contractor, holds no contractor license, employs no plumbers and performs no plumbing work. Every job arranged through this site is performed by an independent, separately licensed professional who contracts directly with the homeowner.
Consumer protection
Business and Professions Code section 7159 governs home improvement contracts, capping the down payment at 10 percent of the contract price or 1,000, dollars whichever is less, and restricting progress payments.