California plumbing contractors are licensed statewide by the Contractors State License Board (CSLB), operating under California Business and Professions Code Section 7000 et seq.
Licenses & Credentials
| Credential | Type | Exam | Application | Exam Fee | Initial | Renewal |
|---|---|---|---|---|---|---|
| C-36 Plumbing Contractor | license | Yes (CSLB (Law and Business examination and C-36 Trade examination, both required)) | $450 (CSLB) | — | $200 (CSLB (sole owner)) | $450 / 2 yr |
C-36 Plumbing Contractor (license)
California's sole statewide contractor credential for plumbing work. Authorises the licensee to contract for plumbing projects on all structure types across California. Required for any person or business contracting for plumbing work where the total cost of labor and materials on one or more contracts on a project is $1,000 or more, a building permit is required, or employee labor is used. There is no separate statewide journeyman or master plumber license in California — journey-level workers employed by a licensed C-36 contractor do not need their own CSLB plumbing license.
- Standard (qualifying individual route). Experience: Four full years of journey-level experience, or as a foreman, supervisor, or contractor in the plumbing trade, within the ten years immediately before the application date. At least one year must be practical hands-on experience; up to three years may be satisfied by verifiable apprenticeship, technical training, or education with written documentation. Training: Completion of the CSLB asbestos open-book examination (submitted with the application; does not certify the holder for asbestos abatement work) Must be 18 years of age or older. Social Security Number or Individual Taxpayer Identification Number required. Fingerprint-based criminal background check required (Live Scan). All experience claims must be verified by a qualified person with firsthand knowledge.
- Qualifying individual for an existing business (RME/RMO route). Experience: Same four-year journey-level experience requirement as the standard route Training: Same asbestos open-book examination requirement A business entity may designate a Responsible Managing Employee (RME) or Responsible Managing Officer/Member (RMO) as the qualifying individual. An RME must be a bona fide employee of the firm, regularly employed at least 32 hours per week or 80% of business operating hours, and may qualify only one active license at a time.
- Arizona reciprocity route. Prerequisite: Active Arizona plumbing contractor license (class C-37, C-37R, K-37, K-77, L-37, or L-77) in good standing for the previous five years Experience: Same four-year journey-level experience requirement; CSLB may waive the C-36 trade examination portion Must submit CSLB Request for Verification of License form completed by the Arizona Registrar of Contractors. The Law and Business examination is always required regardless of reciprocity status. Reciprocity applies to Arizona only for the C-36 classification.
Other fees: Initial License Fee (Non-Sole Owner) — $350 (CSLB); Active Timely Renewal (Non-Sole Owner) — $700 (CSLB); Active Delinquent Renewal (Non-Sole Owner) — $1,050 (CSLB); Inactive Timely Renewal (Sole Owner) — $300 (CSLB); Inactive Timely Renewal (Non-Sole Owner) — $500 (CSLB); Fingerprinting — Dept. of Justice processing fee — $32 (Live Scan operator); Fingerprinting — FBI processing fee — $17 (Live Scan operator)
California CSLB licenses renew every two years. Sole owner and non-sole owner (partnership, corporation, LLC) carry different fee schedules. The license may be placed on inactive status at a lower renewal fee; an inactive license does not permit contracting for work. An application is valid for 18 months from acceptance — if both exams are not passed within that window the application is void and a new application with new fees must be submitted.
Continuing Education
No statewide CE requirement.
No continuing education requirement applies to C-36 Plumbing Contractor licensees. This conclusion is based on the CSLB renewal page (cslb.ca.gov/Contractors/Maintain_License/Renew_License/Completing_Your_Renewal_Application.aspx, verified September 2, 2026), which enumerates all renewal requirements in full and contains no CE step. Verify with CSLB if this changes.
Reciprocity
Interstate reciprocity — formal agreements with:
- Arizona
California has a formal reciprocity programme with Arizona, Louisiana, Mississippi, Nevada, and North Carolina. However, the C-36 Plumbing Contractor classification appears only in the Arizona reciprocal classifications list — not in the Louisiana, Mississippi, Nevada, or North Carolina lists, which cover only general building classifications. Arizona plumbing contractor licence holders who have held their licence in good standing for five consecutive years may apply for a California C-36 under the reciprocity route, and the CSLB may waive the C-36 trade examination. The Law and Business examination is always required regardless of reciprocity status. Confirm current reciprocity status with the CSLB before applying.
Bond & Insurance
Bond: Required. $25,000 contractor's license bond (surety bond) required for all active C-36 licensees. In lieu of a surety bond, a $25,000 cashier's check deposit with CSLB is permitted. The bond protects consumers damaged by defective construction or licence law violations and employees owed unpaid wages.
Insurance: Required. Workers' compensation insurance is required for any C-36 licensee who employs workers. Sole-owner operators with no employees may file a workers' compensation exemption with the CSLB. Proof of workers' compensation coverage must be filed with the CSLB.
Official Sources
Always verify current requirements directly with the official licensing authority — requirements and fees change.
- Contractors State License Board — The state licensing authority for all contractor licences in California, including C-36 Plumbing
- C-36 Plumbing Contractor Classification — Official scope of work definition for the C-36 Plumbing Contractor licence under California Code of Regulations Title 16
- Before Applying for the Examination — CSLB eligibility requirements, bond requirements, qualifying individual rules, and licensing threshold
- Journey-level Experience FAQ — CSLB guidance on what constitutes qualifying journey-level experience for C-36
- List of All CSLB Fees — Official CSLB fee schedule for applications, initial licences, renewals, and miscellaneous services
- Reciprocity Programme and Classifications List — CSLB reciprocal licence classifications by state, confirming C-36 reciprocity with Arizona only
- License Check — Verify the current status of any California contractor licence by name, licence number, or business name
- Apply for a Contractor's Licence — CSLB application process, steps, and documentation requirements
California's plumbing licensing model
California's approach to plumbing licensing differs from most US states. There is one statewide contractor credential for plumbing work: the Class C-36 Plumbing Contractor licence. There is no separate statewide journeyman plumber licence, no apprentice registration with the CSLB, and no master plumber licence at the state level.
The C-36 is a contractor licence — it authorises a person or business to contract for plumbing work. Plumbers employed at journey level by a licensed C-36 contractor do not need their own CSLB plumbing licence to perform work under that contractor's supervision.
Who needs a C-36 licence?
A C-36 licence is required when any of the following conditions apply:
- The total cost of labor and materials on one or more contracts on a project is $1,000 or more
- The project requires a building permit
- Employee labor is used on the project
Performing unlicensed contracting work above the threshold is a misdemeanor under California law.
What the C-36 licence authorises
The C-36 classification covers the full scope of plumbing work on all structure types — residential, commercial, and industrial — including water supply systems, drainage, waste, and venting; gas piping and gas appliances; water heating equipment of all types including solar; piping for medical, dental, commercial, and industrial gas and vacuum systems; backflow preventers, water conditioning equipment, and related health and safety devices; and on-site waste disposal systems.
Eligibility
To qualify for a C-36 licence, the applicant or their designated qualifying individual must demonstrate four full years of journey-level experience in the plumbing trade — or as a foreman, supervisor, or contractor — within the ten years immediately before the application date. At least one year must be verifiable practical hands-on experience; up to three years may be satisfied by apprenticeship training, technical training, or related education, with written documentation.
All experience claims must be verified by a qualified person with firsthand knowledge of the work performed, using the CSLB Certification of Work Experience form.
Qualifying individuals and business entities
The C-36 licence may be held by an individual, partnership, corporation, limited liability company, or joint venture. For business entities, a qualifying individual must be designated — either a Responsible Managing Officer (RMO) or Responsible Managing Member (RMM), or a Responsible Managing Employee (RME) who is a bona fide employee of the firm working at least 32 hours per week or 80% of business operating hours and who may qualify only one active licence at a time.
The licence belongs to the business entity. If the qualifying individual leaves the firm, a new qualifier must be designated promptly or the licence becomes inactive.
Examinations
All applicants must pass two CSLB examinations: the Law and Business examination (covering contractor law, workers' compensation, lien law, and business management) and the C-36 Trade examination (covering plumbing systems, the California Plumbing Code, and installation practices). Both exams are closed-book and multiple choice. Applications are valid for 18 months from acceptance.
All applicants must also complete an asbestos open-book examination and submit it with the application. This does not certify the holder for asbestos abatement work — it is an awareness examination.
Fees
The CSLB fee structure distinguishes between sole owners and non-sole owners (partnerships, corporations, LLCs). Key fees: original application fee $450; initial licence fee $200 (sole owner) or $350 (non-sole owner); timely renewal $450 (sole owner) or $700 (non-sole owner), every two years; delinquent renewal $675 (sole owner) or $1,050 (non-sole owner).
Licences may be placed on inactive status at a reduced renewal fee. An inactive licence does not permit contracting for work.
Bond and insurance requirements
All active C-36 licensees must maintain a $25,000 contractor's licence bond (surety bond) at all times. A $25,000 cashier's check deposit filed with the CSLB may be substituted for the surety bond.
Workers' compensation insurance is required for any C-36 licensee who employs workers. Sole-owner operators with no employees may file a workers' compensation exemption with the CSLB.
Continuing education
The CSLB does not require continuing education for C-36 Plumbing Contractor licensees. Licensees are responsible for staying current with changes to the California Plumbing Code and California Building Standards Code.
Reciprocity
For the C-36 Plumbing Contractor classification, reciprocity applies only to Arizona. Arizona plumbing contractor licence holders who have held an active licence in good standing for five consecutive years may apply for a California C-36 under the reciprocity route. The CSLB may waive the C-36 trade examination for qualifying Arizona applicants, but the Law and Business examination is always required regardless of reciprocity status.
Local permits and requirements
The C-36 is California's statewide contractor credential — it authorises a person or business to contract for plumbing work throughout the state. It does not replace local permitting or inspection requirements.
Plumbing projects may require permits, inspections, or other approvals from the city or county building department where the work is performed. Requirements, fees, and inspection procedures vary by jurisdiction and are administered locally rather than by the CSLB.
Before work begins, homeowners and contractors should confirm which permits or inspections are required by the relevant local building department.
Verifying a California plumbing contractor
The CSLB's online Licence Check tool allows anyone to verify the current status of a California contractor licence by name, licence number, or business name. A valid C-36 licence shows whether it is active, inactive, suspended, or expired, and whether the required bond is in place.
Consumers should always verify a contractor's licence before work begins.
Important: Plumbing licensing requirements change. The information on this page was verified against official sources on the date shown above. Always confirm current requirements, fees, and exam details directly with the relevant licensing authority before applying or hiring.