California CSLB classification
Own the calls you're already running. Classes, paperwork, bonding and business setup handled by one team, in English or Spanish.
✓ Licensed in as little as 90 days. Payment plans available. Se habla español.
What the license covers
The C-36 classification covers the installation and repair of piping, fixtures and appliances for water supply, waste and vent systems, gas piping, water heaters, and the venting and connection of gas-fired appliances. It also covers the maintenance and replacement of those systems.
Homeowners, general contractors, restaurants, apartment owners, and home warranty companies.
Plumbing is emergency work, which means it is recession-resistant and priced accordingly. The gap between a licensed plumbing contractor and a plumber running under someone else's license is usually the difference between hourly wages and margin.
CSLB requirements
Four years of journeyman-level experience in plumbing work, verified by someone who can attest to it. Apprenticeship, technical training and certain degrees can substitute for up to three of those years.
You'll also need a valid Social Security number or ITIN to file the application.
The CSLB Law & Business exam, plus the C-36 trade exam. Both are taken at a CSLB testing center.
Live Scan is required for every applicant and qualifier. Prior convictions don't automatically disqualify you, but they must be disclosed.
Filed with the CSLB before your license is issued. You pay an annual premium to a surety, not the full bond amount.
As of 2026 nearly all licensees must carry workers' comp coverage, including many contractors who previously qualified for the no-employee exemption.
Course options
Every course covers the Law & Business exam and your C-36 trade exam, updated for 2026 code.
8-week online
$895
For contractors who already know the trade and want to test fast.
Most students pick this
4-month online
$1,195
The balance of time and coaching that gets the most people licensed.
7-month online
$1,495
For anyone working full time who needs room to study around the job.
Payment plans available on every course. Not sure which fits? Call and we'll tell you straight.
Related classifications
Most contractors end up holding more than one. These are the classifications that most often sit alongside a C-36.
See all 44 CSLB classifications →
Straight answers
Yes. Gas piping and the connection and venting of gas-fired appliances fall within the C-36 scope.
Yes. Water heater installation and replacement is core C-36 work, including the gas and venting connections.
No. Warm-air heating, ventilating and air conditioning is C-20. Some contractors carry both because the trades overlap on job sites, but the classifications are separate.
Sewer and drain work on the private side falls under C-36. Work in the public right-of-way may require an A classification depending on scope.
Most students are licensed in about three months. The timeline depends on how quickly you finish the course, when you schedule your exams, and current CSLB processing times.
Yes. We complete and file everything — the application, experience verification, bond and insurance documentation. Incomplete applications are the number one cause of delay, so we check every line before it's submitted.
Sí. Todo nuestro equipo es bilingüe. Las clases, la ayuda con la aplicación y todas las actualizaciones están disponibles en español.
Ready when you are
A C-36 lets you pull permits, take jobs over $1,000, and bid the plumbing work you're already good enough to do. Thirty thousand contractors have done it with us.
