Tennessee to Michigan: master plumber license reciprocity

Michigan issues a statewide, person-held Master Plumber license through LARA's Bureau of Construction Codes under MCL 339.6113; the Plumbing Contractor license (Form BCC-329, $300, MCL 339.6111) is the separate business credential that must be represented by a master plumber, and a master may represent only one contractor at a time. Local plumber licensing is preempted by MCL 339.6125(1). A new master applicant must be at least 18, hold a journey plumber license and have gained 4,000 hours of experience as a journey plumber over at least two years immediately preceding the application with no lapse in licensure, document that experience with notarized employer letters, pay the license fee at application ($300 for a licence term of up to three years, prorated outside the April 30-June 30 renewal window), be approved by LARA, and pass the PSI Master Plumber exam (130 questions, 180 minutes, 75% to pass, open book on the 2021 Michigan Plumbing Code, available in person or online; $100 fee). The license renews every three years for $300, and renewal requires a board-approved code-update course within 12 months after each state construction code change. Michigan has no reciprocity with any state; an out-of-state master must pass the Michigan exam, with out-of-state experience credited only after State Plumbing Board review.

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.