Minnesota Plumber License Requirements

Four License Tiers, One State Framework

Minnesota runs a structured licensing ladder overseen by the Department of Labor and Industry (DLI) and the Minnesota Plumbing Board. The standard path builds on the tier below it, although alternative routes exist for some applicants.

Here's the progression:

Registered Unlicensed Plumber (formerly "Apprentice") — The entry point. You need to be at least 18 or hold a GED, pay a $14 registration fee through the DLI iMS portal, and start working under direct on-site supervision of a licensed journeyman or master. No prior experience required. Registration expires June 30 each year, with a $19 renewal fee and two hours of continuing education.

Licensed Journeyworker Plumber — After accumulating 7,000 hours of documented practical experience (minimum four years due to the 1,750-hour annual cap), you can apply for the journeyman exam. The exam costs $50, and you need a 70% score to pass. Initial license activation is $40, and renewals run $53 every two years with 16 hours of CE.

Licensed Master Plumber — Requires at least one year (1,750 hours) of practical experience as an active journeyman. The master exam has a $50 fee and a 70% passing score. Initial activation costs $80, and biennial renewals are $93. When designated as the RLI for a licensed plumbing contractor, the master license is the only individual credential that authorizes permit-pulling and serving as a Responsible Licensed Individual (RLI) for a contracting company.

Licensed Plumbing Contractor — A business license, not a personal one. The company must designate an active master plumber as its RLI; the RLI may be a W-2 employee, owner, officer, or member of the business. The company must also secure a $25,000 surety bond, carry general liability insurance, provide workers' compensation coverage or a validated statutory exemption if it has no employees, and pay a $188 license fee.

The Experience Hours That Trip People Up

The single biggest administrative hurdle is the 7,000-hour experience requirement for journeyman eligibility. The DLI doesn't just count total hours — they require specific distribution across categories:

• 2,000 hours in water distribution installation
• 2,000 hours in drain, waste, and vent (DWV)
• 1,000 hours in fixture installation
• 2,000 hours discretionary (maintenance, repairs, or additional core-category work)

Miss a category minimum and the DLI rejects your exam application, even if your total hours exceed 7,000. You also can't bank more than 1,750 hours per registration year (July 1 through June 30), so the minimum calendar path is four years regardless of overtime.

Where Minneapolis and St. Paul Add a Layer

Most of Minnesota follows the single state license. Minneapolis and St. Paul add a local requirement: a Certificate of Competency ("Comp Card") at the journeyman and master levels. The two cities maintain a reciprocal agreement — earn one city's card and the other's is available without re-examination — but it's a separate filing and fee on top of the state license.

Reciprocity With Other States

Minnesota only has formal reciprocity with North Dakota and South Dakota. If you're licensed in either state by passing a written state-level exam, you can transfer without re-testing (provided you've held the license at least one year in good standing). Plumbers from all other states must apply and sit the Minnesota exam. Out-of-state experience credit is capped at two years (3,500 hours) for unlicensed work.

What This Actually Costs

Here's every fee in the pipeline:

The licensing fees themselves are modest. The real cost is the four-plus years of careful hour documentation needed to reach journeyman — and the consequences of losing tracked hours during an employer change because a supervising master wouldn't sign the Form CC0100.

The Minnesota Plumber License Guide walks through every transition point from registration to contractor setup, with fillable trackers for experience hours and a step-by-step business launch checklist.

See more Minnesota guides →