Last updated: August 28th, 2026
A California C-36 plumbing contractor license is issued by the Contractors State License Board (CSLB). A contractor license is generally required when a project costs $1,000 or more in combined labor and materials, requires a building permit, or uses employee labor or additional workers. The minor-work exemption applies only when the project is under $1,000, does not require a permit, and does not use employee labor.
Here is what you generally need to qualify:
California continues to offer strong opportunities in the plumbing trade. California EDD data for the first quarter of 2026 reports a mean hourly wage of $40.65 and median hourly wage of $35.96 for plumbers, pipefitters, and steamfitters. EDD also projects employment in the occupation to grow 8.4% from 2022 to 2032, from 46,500 to 50,400 jobs statewide.
But obtaining a C-36 license involves more than passing an exam. Experience verification, application accuracy, bonding, fingerprinting, and CSLB requirements can all affect how smoothly your application moves through the process.
The C-36 Plumbing classification covers work involving the supply of safe water and proper disposal of fluid waste from structures and fixed works.
CSLB’s official C-36 scope includes work involving:
The classification includes suspended space-heating units but does not include forced warm-air units.
For the legal definition, see CSLB’s official C-36 Plumbing Contractor classification.
To qualify, you generally need at least four years of qualifying experience in the C-36 classification within the 10 years immediately preceding your application.
Qualifying experience can include experience as a:
A journeyman is a fully qualified and experienced worker who can perform the trade without supervision. Helper, trainee, laborer, and basic assistant-level work does not qualify at the same level.
CSLB requires your experience to be documented on a Certification of Work Experience form. The person certifying your experience must have firsthand knowledge of the work you performed.
Depending on how your experience was gained, a certifier may include an employer, contractor, foreman, supervisor, fellow journey-level worker, building inspector, architect, engineer, or homeowner.
Be prepared to provide supporting documentation if CSLB requests additional verification.
Education is not required to obtain a California contractor license.
However, qualifying education or technical training may provide credit toward part of the four-year experience requirement. The amount of credit depends on the education or training being submitted, and at least one year must be practical experience.
Official transcripts and other applicable documentation may be required when requesting education credit.
Applicants who need to take the examinations generally complete an Application for Original Contractor License.
Be precise when describing your plumbing experience. Instead of simply writing “performed plumbing,” describe actual trade duties such as installing DWV systems, running water-supply piping, installing gas piping, or installing water heaters.
The current original contractor license application fee is $450.
Follow CSLB’s current submission instructions for your application type. Sole-owner applicants also have an online application option.
Avoid relying on a fixed estimate for processing time because CSLB processing times fluctuate.
After CSLB accepts the application, applicants who are required to be fingerprinted receive instructions for submitting fingerprints.
Fingerprints are compared with records maintained by the California Department of Justice and FBI.
A criminal conviction does not automatically disqualify you from obtaining a contractor license.
Applicants also are not required to disclose criminal convictions on the license application. CSLB receives criminal-history information through the fingerprint process and may request additional mitigating or rehabilitation information when appropriate.
Before your license can be issued and maintained as active, you need to meet the applicable bond and insurance requirements.
Importantly, C-36 is not one of the classifications currently required to carry workers’ compensation insurance regardless of employee status. That mandatory rule currently applies to C-8, C-20, C-22, C-39, and C-61/D-49 contractors.
Most C-36 applicants who do not qualify for an exam waiver must pass two examinations:
CSLB examinations are administered through PSI.
The exams are:
The current C-36 Plumbing examination is divided into five major sections:
1. Planning and Estimating — 22%
2. Underground and Rough Systems — 22%
3. Finish Plumbing Installations — 20%
4. Service, Repair, and Remodel Plumbing Systems — 19%
5. Safety — 17%
These percentages are approximate and come from CSLB’s current C-36 examination study guide for examinations scheduled on or after March 1, 2025.
Current CSLB fees include:
California currently has no general continuing-education requirement for renewing a C-36 contractor license.
California has reciprocity agreements with Arizona, Louisiana, Mississippi, Nevada, and North Carolina, but reciprocity is classification-specific. Holding a plumbing license in one of those states does not automatically mean it is reciprocal with California’s C-36 classification.
For example, CSLB’s current reciprocal-classifications list identifies certain Arizona plumbing classifications as reciprocal with California C-36. Applicants should check CSLB’s current reciprocal-classifications list for their exact license before assuming they qualify.
When reciprocity applies, CSLB may waive the trade examination, although CSLB retains the right to require it. The applicant must still take the California Law & Business examination.
Once your license is issued, keep it in good standing by:
A lapse in required bonding, insurance, or renewal can result in your license becoming suspended or expired.
There is no guaranteed timeline. Processing depends on CSLB’s current workload, whether your application requires corrections or experience verification, fingerprint processing, and PSI exam availability.
Checking CSLB’s live processing times is more reliable than using a fixed estimate.
Not necessarily. A C-36 contractor with no employees may currently qualify for an exemption if all other exemption requirements are met. C-36 is not currently one of the classifications automatically required to carry workers’ compensation regardless of employee status.
Contracting without the required license can lead to fines, misdemeanor prosecution, possible jail time, and other consequences. California law can also prevent an unlicensed contractor from recovering compensation for work that required a contractor license.
Use CSLB’s Check a License tool to review the contractor’s license status, classifications, bond information, workers’ compensation information, and publicly disclosed disciplinary information.
Potentially. Experience obtained outside the United States may qualify if it meets CSLB’s experience requirements and can be adequately verified. Additional documentation, translations, or evaluations may be required depending on the records being submitted.
Obtaining your California C-36 plumbing contractor license can give you the ability to operate your own plumbing contracting business and take on projects that require a licensed contractor.
The key is getting the application right: qualifying experience, proper documentation, exam preparation, bonding, fingerprinting, and final licensing requirements all matter.
Contractors License Guru can help with application preparation, experience documentation, and C-36 exam preparation so you can move through the process with fewer unnecessary delays.
