How to Check a California Plumbing License Before Work Starts

What the C-36 license is

Plumbing contractors in California are licensed by the Contractors State License Board. The relevant classification is C-36, the plumbing contractor license, which covers supplying safe water at adequate volume and temperature and disposing of fluid waste from a property.

Some contractors hold several classifications. A company doing slab leaks and pipe restoration might carry C-36 alongside other classifications for the associated work. That's normal and it's visible on the license record.

The advertising rule, and the one it gets confused with

Two different requirements get mixed up constantly, so it's worth separating them.

Business and Professions Code 7030.5 is the advertising rule. A licensee must include its license number in construction contracts, in subcontracts and calls for bid, and in all forms of advertising. A website is advertising, which is why you see numbers in the footers of contractor sites across the state.

Business and Professions Code 7030 is a different thing. That's the notice about the CSLB having jurisdiction over complaints, with the four year and ten year windows, and it's a written contract requirement in a minimum type size. It isn't an advertising requirement, and its absence from a website isn't a violation.

How to check a license in two minutes

The CSLB Check A License tool is free and public. You can search by license number, by business name or by personnel name.

1. Ask the contractor for their license number, or read it from their advertising.
2. Open the CSLB Check A License page and search the number. California license numbers are numeric and don't exceed eight digits.
3. Confirm the status reads active, and that the classification includes C-36 for plumbing work.
4. Check the expiry date, and check the bond information is current.
5. Check the workers compensation section. A contractor with employees must carry it, or hold a valid exemption.
6. Look at the complaint disclosure section for any disclosable actions.
7. Confirm the business name on the license matches the name on the quote you were given.

Searching by name when you only have a name

The CSLB name search has a quirk worth knowing. Where a business name contains a personal first and last name, the last name is entered first. A company called John Smith Construction is searched as Smith John Con.

If a name search returns nothing at all, that's worth pausing on. It can be a spelling difference or a trading name, and it can also mean the entity you're dealing with isn't the licensed one.

What to ask on the doorstep

Verification isn't only a paperwork exercise before the visit. There are three things worth confirming when someone actually arrives.

• Ask for the license number and check the name on the record matches the company on the invoice.
• Ask for proof of liability insurance, and for workers compensation if anyone other than the owner will be on site.
• Ask for the scope and the price in writing before work starts, including what's excluded.

Check the number of whoever actually turns up

A license number only means something when it belongs to the business doing your work. The number to verify is the one on the van in your driveway, not one printed on a website.

Get it before work begins, run it through Check A License, and confirm the classification and the status yourself. Two minutes, no cost, and it's the single most useful thing you can do before handing over a deposit.

Sources

• CSLB, Check A License
• CSLB, C-36 plumbing contractor classification

Read next

• Whole House Repipe Replacing the supply lines through the whole house, usually in PEX or copper, usually in two to five days.
• Slab Leak Detection and Repair A line under your foundation is leaking. Finding it accurately is most of the job, and it can be done without tearing up the whole floor.
• Emergency Plumbing Shut the water off at the main. Then call.
• All guides Costs, permits, diagnostics and who to call