MISSOURI · plumber
Not regulated at state level (municipal licensing)
City and county authorities (no statewide plumbing contractor license) →Scope and Structure
Missouri does not issue a statewide plumbing contractor or statewide journeyman plumber license. Plumbing work is licensed and regulated at the city or county level throughout Missouri, with the largest and most detailed regimes operating in Kansas City, St. Louis, St. Louis County, Springfield, Columbia, and Jefferson City. Missouri's state-level plumbing statute, Revised Statutes section 341.170, directs that each city with a population of 15,000 or more and each third-class county adopt rules and regulations for the materials, construction, and inspection of plumbing and sewerage, and that cities examine and license plumbers. Source: Missouri Revised Statutes section 341.170 (https://revisor.mo.gov/main/OneSection.aspx?section=341.170).
City Licensing Pattern
Typical Missouri city plumbing regimes require an applicant to document journeyman-level experience (often 4 or 5 years, or a completed U.S. DOL-registered apprenticeship), pass a city-administered or third-party-administered plumbing exam covering the local plumbing code (frequently the International Plumbing Code or Uniform Plumbing Code with local amendments), provide proof of insurance, and post a local plumber's bond. Contractor (master) licenses require additional years of journeyman experience and a separate exam. Fees, bond amounts, and code adoptions vary by jurisdiction.
Largest Jurisdictions.
- Kansas City, MO. Administered by the City of Kansas City Department of Regulated Industries. Maintains journeyman plumber, master plumber, and plumbing contractor registrations with their own exams and bonding requirements. - St. Louis (City). Administered by the City of St. Louis Building Division. Maintains its own plumbing license categories, exams, and bond requirements. - St. Louis County. Operates a separate county-level plumbing license regime that may be recognized within unincorporated St. Louis County and many incorporated municipalities within the county. - Springfield. Administered by the City of Springfield Department of Building Development Services.
Missouri Division of Professional Registration
The state Division of Professional Registration at pr.mo.gov maintains an advisory role for plumbing under Missouri Revised Statutes Chapter 341 but does not issue individual plumber or plumbing contractor licenses that function as a statewide credential replacing local licensure. A Missouri plumber intending to work in multiple cities must qualify under each city's licensing regime, with reciprocity or credit for passed exams handled city-by-city.
Contrast with Electrical
Missouri created a Statewide Electrical Contractor license under Revised Statutes sections 324.900 to 324.945 (the Office of Statewide Electrical Contractors, OSEC). There is no analogous statewide plumbing statute; plumbing remains municipal.
What to Expect
A plumber building a Missouri business should plan to (1) qualify and test under each city or county where you will work, (2) carry liability insurance and post local bonds as each ordinance requires, (3) form and register the business entity with the Missouri Secretary of State, and (4) register tax accounts with the Department of Revenue and employer accounts with the Missouri Division of Employment Security. Verify every municipal requirement against the current ordinance before estimating or permitting.