Missouri Plumbing Apprenticeship

How Apprenticeships Work in Missouri

Missouri plumbing apprenticeships are registered and supervised at the local level. There is no state apprenticeship board for plumbing — each city and first-class county sets its own registration process, hour requirements, and supervision standards. Before you start accumulating hours, register with the specific board where you plan to get licensed. Hours worked before registration may not count toward your exam eligibility.

Registration by Jurisdiction

St. Louis County: Formal registration with the Board of Plumbing Examiners is required. Age 18+, high school diploma or GED. Registration fee: $10. You must work under a locally licensed master plumber.

Kansas City: No registration fee. You must be age 18+ with a high school diploma and enrolled in an approved apprenticeship program under a licensed master's supervision.

St. Louis City: Registration with the Board of Examiners of Plumbers and Drainlayers. Fee: $10.

Jefferson City: Age 18+, registration through the municipal application. Fee: $14.

Springfield: Apprentice application through the Trade Certification office.

Hour Requirements

Most jurisdictions require 8,000 to 10,000 hours of on-the-job training, typically completed over four to five years of full-time work. The exceptions:

• Kansas City: Allows exam eligibility after just 2 years of verified experience
• Springfield: Accepts 4 years under a master or 6 years of trade experience for the journeyman path

St. Louis County counts 1,500 hours as one year, so five years of apprentice experience translates to 7,500 documented hours minimum.

Supervision Rules

Every apprentice must work under the direct supervision of a licensed master plumber. St. Louis County enforces the strictest staffing ratio in the state: the total number of apprentices at a firm cannot exceed the combined number of licensed journeymen and master plumbers employed there.

During labor shortages, St. Louis County masters can apply for a temporary waiver allowing up to two additional apprentices. The waiver requires submitting quarterly manpower and man-hour reports to the board.

Documenting Your Hours

This is where apprenticeships succeed or fail. Local boards require documentation in specific formats:

• Notarized employer affidavits listing dates, hours, and scope of work
• W-2 tax forms confirming employment
• Trade school certificates (where classroom hours supplement field time)
• DOL apprenticeship records (if you went through a registered program)

Keep your own independent log from day one. If an employer goes out of business or refuses to sign your affidavit, you need a fallback record. Some boards accept tax records combined with coworker attestation, but confirm that with your specific board before you rely on it.

The Experienced Apprentice Fast Track

St. Louis County offers an "Experienced Apprentice Plumber" registration for candidates who have already been working in the trade. To qualify:

• At least 2.5 years of documented trade employment
• Minimum 500 hours of approved classroom training
• Completion of the 10-hour OSHA Safety Training for Construction course

This path accelerates your timeline by crediting prior work experience, but the classroom and OSHA requirements are strict prerequisites.

Union vs. Open-Shop Pathways

Missouri has both union and non-union apprenticeship routes. The Missouri PHCC and United Association local chapters offer structured training programs with DOL-registered credentials. These programs provide formal classroom instruction, standardized hour tracking, and direct connections to licensed contractors.

Non-union apprentices build their hours through private employment under a licensed master. The licensing outcome is identical — both paths lead to the same journeyman exam — but non-union apprentices bear more responsibility for their own documentation.

The Missouri Plumber License Guide includes an hour tracker template formatted for local board submissions and a jurisdiction-by-jurisdiction comparison of apprentice requirements.

See more Missouri guides →