How to Get a Plumbing License in Missouri

Missouri Has No Statewide Plumbing License

If you searched the Missouri Division of Professional Registration looking for a plumbing application, you came up empty — and that is the correct result. Missouri does not issue a statewide plumbing license. Under RSMo Chapter 341, licensing authority belongs entirely to cities with populations of 15,000 or more and first-class counties. Each one runs its own board of plumbing examiners, sets its own experience thresholds, chooses its own exam vendor, and issues its own trade card.

That means the license you earn in Kansas City carries zero automatic authority in St. Louis County, Springfield, or any other jurisdiction. A plumber operating in three metro-area municipalities needs three separate licenses, separate compliance bonds where required, and potentially three different exams.

The Four License Levels

Every Missouri jurisdiction recognizes some version of the same progression, though the specifics vary:

Apprentice — You register with the local board (St. Louis County charges $10; Kansas City charges nothing) and work under the direct supervision of a licensed master plumber. Most jurisdictions require 8,000 to 10,000 hours of on-the-job training over four to five years, though Kansas City accepts candidates after just two years of verified experience.

Journeyman — After completing your hours and passing the local trade exam, you can perform plumbing work independently but cannot pull permits or contract directly with property owners. You must remain employed by a licensed contractor or master plumber.

Master Plumber — The highest individual credential. You need one to five additional years as a journeyman (depending on jurisdiction), and you must pass a separate master exam. A master plumber can serve as the qualifying party for a contracting business and pull permits.

Plumbing Contractor — This is a business-level license. The company designates a full-time master plumber as its supervisor, registers with the Secretary of State, secures any required local surety bond, and carries general liability and workers' compensation insurance.

Experience Requirements by Jurisdiction

The hours you need depend on where you apply:

• Kansas City: 2 years verified under a master (apprentice to journeyman), then 1 year as journeyman (to master)
• St. Louis City: 5 years apprentice experience, then 5 years as journeyman
• St. Louis County: 5 years apprentice, then 2 years as journeyman
• Springfield: 4 years under a master or 6 years practical (journeyman), 4 years as journeyman or 10 years practical (master)
• Jefferson City: 4 years / 8,000 hours (journeyman), then 2 years / 12,000 total hours (master)
• Columbia: 2–4 years (journeyman), then 2 years / 12,000 total hours (master)

Document every hour. Local boards require notarized employer affidavits or W-2s as proof. If a previous employer refuses to sign, some boards accept tax records combined with coworker attestation — but get that confirmed in writing with your specific board before you apply.

How Exams Work

Missouri jurisdictions use different testing vendors:

• ICC exams via Pearson VUE: St. Charles County, Jefferson City, Springfield
• Prometric or ICC: Kansas City
• IAPMO (locally administered): St. Louis County
• Proprietary written and practical exams: St. Louis City

Passing scores range from 70% (Kansas City, Jefferson County) to 75% (Springfield, Jefferson City, St. Charles County). Score reports go directly to the local building division, which issues your trade card once everything checks out.

What It Costs

Between exam fees, application fees, bonds, and insurance, the total startup cost to become a licensed plumbing contractor varies by jurisdiction. Individual trade card fees are modest — $10 to $117 depending on jurisdiction and license level — while contractor licensing and administrative fees can reach $233. Surety bonds ($5,000 in Jefferson City up to $25,000 in Jefferson County) and liability insurance ($500,000 to $1,000,000 minimums) represent the bigger financial commitment.

Your First Steps

Pick the jurisdiction where you plan to work and contact that board directly. Ask for the current application packet, experience documentation format, exam vendor, and fee schedule. Missouri's decentralized system means generic advice only gets you so far — the details that matter are always local.

If you plan to work across multiple jurisdictions, the Missouri Plumber License Guide maps the requirements for seven major Missouri jurisdictions side by side, with checklists for each license level and a tracker for documenting your hours in the format local boards accept.

See more Missouri guides →