Moving to Missouri as a master plumber: every state's rule
Missouri does not issue a statewide master plumber license, so there is no reciprocity to speak of. Here is what that means in practice.
Missouri master plumber
Licensed by cities and counties
Missouri issues no statewide master plumber or plumbing contractor license. RSMo chapter 341 leaves plumber licensing to cities over 15,000 and first-classification counties, whose boards examine master plumbers, set fees and license terms and (in counties) require master plumber and master drainlayer surety bonds; no state agency licenses the trade and the voluntary statewide contractor license that exists for electrical work has no plumbing counterpart. The master credential therefore exists only locally: Springfield's Master Plumber certification (4 years as a certified journeyman or 10 years' experience, ICC exam, $50), Kansas City's plumbing contractor license qualified by a supervisor holding a certificate of qualification (Prometric or ICC exam, $60 application, $181 four-year renewal; contractor license $55 application, $181 issuance), St. Louis County's Master Plumber license and certified contractor list, and the City of St. Louis Plumbers and Drainlayers Board of Examiners' master plumber and drainlayer licenses. An out-of-state master plumber license carries no state-level recognition; Springfield accepts an identical ICC, Prometric, Experior or Block exam score of 75% or better in place of retesting and Kansas City may accept a comparable exam it deems equivalent, while the St. Louis County and City of St. A master arriving from another state should expect to qualify in each jurisdiction separately and then obtain that jurisdiction's contractor license and bond to pull permits.
How local licensing works in Missouri
How local licensing works. There is no state plumbing board. Under RSMo chapter 341, city boards of examiners (cities over 15,000) and county boards of plumbing and sewer inspection (first-classification counties) examine master plumbers; § 341.170 sets the county master plumber qualifications, § 341.180 the application fees, license terms and re-examination rules, and § 341.200 requires master plumbers and master drainlayers to post surety bonds. The master license is the credential that lets a plumber pull permits and run a plumbing business, and each jurisdiction issues and enforces its own.
St. Louis County. The Plumbing Licensing office (41 South Central Avenue, Clayton, 314-615-3741) issues Master Plumber licenses and publishes a Certified Contractors list; the Board of Plumbing Examiners meets the first Thursday of each month at 8:00 a.m., and renewals carry PEU continuing-education requirements. Louis.** The Building Division's Plumbers and Drainlayers Board of Examiners licenses master plumbers and drainlayers and reviews licensing matters and complaints for plumbing and drainlaying work in the city; permits are issued to city-licensed contractors. Every licensed contractor must employ a full-time supervisor who holds a Kansas City certificate of qualification in the plumbing trade, obtained on an application with notarized references and a passing score from a recognized agency such as Prometric or ICC ($60 application, first four-year certificate free, $181 renewal); the city 'may accept comparable examinations from other jurisdictions if deemed equivalent or superior'. Whether a separately titled master plumber license, plumbing-specific experience hours or named reciprocity with Kansas jurisdictions exist could not be confirmed because kcmo.gov and both fallback routes were blocked on 2026-09-16.
Springfield. Building Development Services certifies Master Plumbers: 4 years as a certified journeyman plumber or 10 years of satisfactory experience in the trade, documented on notarized employer experience forms and approved by the board (first Thursday monthly, 5:00 p.m., Busch Building; approval to test good for one year). The exam is the ICC master plumber exam through Pearson Vue (about $125 paid to Pearson Vue), 75% to pass; the certification card costs $50 with $50 annual renewal, and a master must file a Master Registration form to qualify a contracting business (Master Resignation form on leaving). Out-of-state treatment: 'Reciprocity from another jurisdiction' applicants submit the same experience documentation plus an exam score notification of 75% or better from Prometric, Experior, Block or ICC (Pearson Vue) for the identical exam Springfield requires; otherwise they test. Springfield also certifies Master Gas fitters (4 years as a certified gas journeyman, or 4 years as a master mechanic or plumber plus 2 years as a gas journeyman).
Columbia and others. Columbia, St.
- St. Louis County (Transportation and Public Works, Plumbing Licensing / Board of Plumbing Examiners)
- City of St. Louis (Building Division, Plumbers and Drainlayers Board of Examiners)
- Kansas City (City Planning and Development, contractor licensing and certificates of qualification)
- Springfield (Building Development Services, Trade Certifications)
- Columbia (Community Development, Building and Site Development)