Mississippi to Idaho: master plumber license reciprocity

State contractor license (business). MSBOC issues commercial and residential contractor licenses to companies through a Certificate of Responsibility. The commercial Mechanical major classification 'involves all aspects of heating, cooling, refrigeration and associated equipment piping and ductwork as well as plumbing work' and carries 15 specialties including Plumbing, Process Piping, Underground Utilities, Fueling Systems and Irrigation Systems (all test required); an applicant may instead take only the Plumbing specialty. The qualifying party (owner, officer or responsible managing employee) passes the PSI open-book trade exam and the Mississippi Law and Business Management exam; fees are $400 application ($400 annual renewal, $100 per additional classification), general liability insurance of $300,000 per occurrence / $600,000 aggregate, and a CPA-reviewed financial statement showing net worth of $50,000 for a major classification or $20,000 for a specialty. Residential Plumbing (Residential Plumbing exam) and Residential Mechanical (Residential HVAC and Residential Plumbing exams) require the Law and Business exam, a $50 application fee ($100 per additional classification, $100 renewal) and proof of liability insurance with no minimum.

MSBOC exam waivers for out-of-state qualifying parties. Reciprocity 'applies to waiver of a trade exam requirement only' ($50 per exam waived, plus a $25 verification fee) after the origin board completes MSBOC's Reciprocity Verification Form; the applicant must have held the origin license for one year and passed that board's exam. Plumbing waivers are available for the Alabama Plumbers and Gas Fitters Examining Board (commercial Plumbing exam only; current license, Alabama exam taken), Ohio CILB (Plumbing; no discipline in the last year), the South Carolina Residential Builders Commission (Residential Plumbing; no discipline in three years) and Tennessee ('the only state that waives Mechanical and Plumbing'; no discipline in the last year). The Alabama General Contractors Board entry waives 'all exams but Mechanical & Plumbing', Arkansas excludes 'any type of Mechanical (i.e. Plumbing, Boilers, Process Piping, HVAC)', and Louisiana 'CAN WAIVE HVAC BUT NOT MECHANICAL OR PLUMBING'; Georgia, North Carolina, the South Carolina Contractors Licensing Board, Florida and California agreements do not reach plumbing. Separately, Form UROL under the Universal Recognition of Occupational Licenses Act (Miss. Code 73-50-2) waives the trade exam for an individual who has established Mississippi residency and held a similar license in any state for at least one year, and the Military Family Freedom Act (73-50-1) applies to military members and families. Every path still requires the Business and Law exam and full application review.

Southaven. Master trade license $100: application, photo ID of the license qualifier, certificate of liability insurance, a $10,000 general surety bond in favor of the city, an active MSBOC contractor's license certificate and the company EIN. An out-of-state applicant without an MSBOC license must provide a letter of good standing from a municipality where their license is active and may not take residential projects or commercial projects over $50,000; reciprocity questions are referred to MSBOC. Confirmed for mechanical and electrical on 2026-09-15; the plumbing card was not separately confirmed because the form could not be reopened on 2026-09-16.

Gulfport. Contractor license issued to the qualifying party ($100, waived with an MSBOC Certificate of Responsibility): notarized application, current MSBOC license if any, five reference letters (waived with an MSBOC license), $100,000/$300,000 liability insurance naming the city, home-jurisdiction privilege license and photo ID. No reciprocity provision.

Jackson, Hattiesburg, Biloxi, Tupelo. Master plumber programs in these cities could not be verified from an official page in this pass (Jackson redirected, Hattiesburg plumbing ordinance 404); contact each building department.