Requirements, license levels, and the issuing authority, sourced from California's official board.
CSLB restructured its site and several older classification and renewal URLs 404; the figures above come from CSLB's current fee list, examination FAQ, qualifying-experience page, bond page, reciprocity pages and the C-36 examination study guide. CSLB does not publish a passing percentage. Its examination FAQ says candidates are informed at the test site of the percentage of correct answers needed to pass, a passing report does not show the overall score, and only a failing report shows the score and section performance. The 72% figure is not on any CSLB page checked and has been removed rather than restated.
| Requirements | California licenses no individual journeyman or apprentice plumber; the only state plumbing credential is the CSLB C-36 Plumbing Contractor license. Four years of journey-level or higher plumbing experience are required, of which up to three years may be substituted by schooling or apprenticeship, and a $25,000 contractor bond must be filed before an active license issues (the bond rose from $15,000 to $25,000 effective January 1, 2023 under SB 607). A $25,000 bond of qualifying individual applies where the license is qualified by an RME, or by an RMO owning under 10% of the voting stock. The C-36 trade examination is weighted planning and estimating 22%, underground and rough systems 22%, finish plumbing installations 20%, service, repair and remodel plumbing systems 19%, and safety 17% (percentages approximate, for examinations scheduled on or after March 1, 2025). Its reference list is built on the 2025 California Plumbing Code and 2025 California Mechanical Code (Title 24, IAPMO), the California MUTCD 2014 revision 8, and the Cal/OSHA General Industry, Electrical, and Construction Safety Orders (Title 8). CSLB SIDE - fees, from CSLB's published fee list: application for an original license $450 (non-refundable); initial license fee, which covers the first two-year period, $200 sole owner / $350 non-sole owner; additional classification on an existing license $230; replacing the qualifier $230; adding personnel or a limited partner $125 each; license reactivation $450 sole owner / $700 non-sole owner; joint venture application $800; asbestos certification $125; hazardous substance removal certification $125; home improvement salesperson registration $200; duplicate certificate $25; business name change $100; certified license history $67. Fingerprinting is $32 to the Department of Justice plus $17 to the FBI plus the Live Scan rolling fee. Examination fees are paid directly to PSI and are no longer processed by CSLB. CSLB experience rule: at least four years of experience in the classification applied for, credited only at journey level or as a foreman, supervising employee, contractor or owner-builder. CSLB defines a journeyman as a fully qualified experienced worker, as opposed to a trainee, helper, labourer, assistant or apprentice, who can perform the trade without supervision, or a person who has completed an apprenticeship program. Up to three of the four years may be credited to schooling or apprenticeship under 16 CCR 825, but at least one year must be practical experience: a maximum of 1.5 years for an A.A. degree in building or construction management; a maximum of 2 years for a four-year degree in accounting, architecture, business, economics, mathematics, physics or a trade-related field, a professional law degree, or substantial related college coursework; and a maximum of 3 years for a Certificate of Completion of Apprenticeship from an accredited apprenticeship program or union certification, or a four-year degree in construction technology or management or related engineering. Official sealed transcripts must be sent to CSLB for the credit to be evaluated. EXAMINATION. PSI delivers CSLB's examinations by computer at 20 locations in California and 21 nationwide, 8:00am-5:00pm Monday to Saturday. Every applicant sits two examinations, Law and Business plus the trade examination. Both are CLOSED BOOK - no reference materials may be used - and multiple choice with four choices and one best answer; a calculator is provided and there is no penalty for guessing. Each examination is allowed 3.5 hours. CSLB does not publish the passing percentage: it states that candidates are informed at the test site of the percentage of correct answers needed to pass. At the end of the session the candidate is handed a printed pass/fail report; a passing report does not show the overall score, while a failing report shows the overall score and the performance by section. A failed examination may be retaken after 21 calendar days, provided the application has not passed its 18-month void date. |
| Reciprocity | There is no California journeyman or apprentice plumber license to reciprocate; only the C-36 contractor license exists. For the C-36, CSLB's reciprocity program covers Arizona, Louisiana, Mississippi, Nevada and North Carolina, but a classification only reciprocates if it appears on CSLB's Reciprocal Classifications List, and on that list the only plumbing mappings are Arizona's: C-37 Plumbing Including Solar, C-37R Plumbing, K-37 Plumbing, K-77 Plumbing Including Solar, L-37 Plumbing and L-77 Plumbing Including Solar all map to California's C-36. No plumbing classification is listed for Nevada, Louisiana, Mississippi or North Carolina, so in practice the C-36 reciprocity route runs through Arizona. The applicant must have held an active license in good standing in the reciprocal state for the previous five years, file a Request for Verification of License completed by that state's licensing authority, and file the Application for Original Contractor's License. A separate exam-waiver route exists for the General Building (B) classification only, through the NASCLA Commercial General Builders Examination; it does not reach the C-36. |
| Renewal | Two-year renewal, expiring two years from the last day of the issue month; there is no state continuing-education requirement for contractors. Renewal fees from CSLB's fee list: active timely $450 sole owner / $700 non-sole owner; active delinquent $675 / $1,050; inactive timely $300 / $500; inactive delinquent $450 / $750. (The $20 C-10 surcharge applies to the electrical classification only, not to the C-36.) Home improvement salesperson registration renews at $200 timely, $300 delinquent. |
| Notes | CSLB restructured its site and several older classification and renewal URLs 404; the figures above come from CSLB's current fee list, examination FAQ, qualifying-experience page, bond page, reciprocity pages and the C-36 examination study guide. CSLB does not publish a passing percentage. Its examination FAQ says candidates are informed at the test site of the percentage of correct answers needed to pass, a passing report does not show the overall score, and only a failing report shows the score and section performance. The 72% figure is not on any CSLB page checked and has been removed rather than restated. |
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Sources: cslb.ca.gov, www.cslb.ca.gov, www.cslb.ca.gov, www.cslb.ca.gov. Always confirm current requirements with the issuing authority.
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