Tennessee to Kentucky: master plumber license reciprocity

Kentucky issues a statewide Master Plumber license through DHBC's Division of Plumbing under KRS Chapter 318 and 815 KAR 20:030. In-state applicants typically hold a Kentucky journeyman plumber license for at least two of the past five years and work under a licensed master for at least two years; Kentucky professional engineers with sufficient mechanical-engineering experience may also qualify. An applicant who holds a valid plumbing license issued by another state for at least two of the past five years, or who practiced as the equivalent of a master for four consecutive years in a state that does not license plumbers, may sit for Kentucky's exams but must still pass both the Kentucky journeyman examination (75% each portion) and the Kentucky master examination (80% each portion). The master exam is written plus drawing (more complex than the journeyman exam); the exam fee is $150 (Form PLB-3) and the license fee is $250 (Form PLB-1), prorated 7–18 months to the birth month. Masters renew annually at $250 with six CE hours and proof of insurance required by KRS 318.030. 815 KAR 20:030 names no partner states and does not waive the Kentucky exams.

Tennessee does not issue a master plumber license. The state-level plumbing credentials are (1) the Limited Licensed Plumber (LLP), a personal license for work under $25,000 where the Division of Fire Prevention inspects, which the Board does not treat as a master equivalent and for which it has no exam-waiver agreements, and (2) a contractor license with the CMC-A (plumbing) or CMC (full mechanical: plumbing and HVAC) classification, issued to a business that names a qualifying agent and required for plumbing projects of $25,000 or more. CMC-A and CMC candidates need Board pre-approval ($50) before the plumbing or full-mechanical trade exam; every contractor also takes the Tennessee Business and Law exam (Prov from 2026-07-01; scores typically valid two years). Initial contractor application fee $250. The Board's trade-exam-waiver form lets a contractor whose origin board verifies a comparable plumbing or mechanical exam skip the Tennessee trade exam but not Business and Law, and it cannot be used for the LLP: Ohio plumbing maps to CMC-A, South Carolina plumbing to CMC-A, and Louisiana, Mississippi and West Virginia mechanical licenses to CMC. That waiver is contractor-to-contractor only (Ohio's OCILB listing of Tennessee as a plumbing-contractor partner is the same relationship from Ohio's side). Master plumber licenses proper exist only locally; Nashville's MPE Board issues a master plumber certificate. An out-of-state master plumber has no statewide personal recognition: to contract for $25,000 or more they need the CMC-A or CMC contractor license; to pull small-job permits they need the LLP where it is accepted, or the local master card where it is not.