Minnesota's plumbing ladder runs from registered unlicensed plumber to master, with 7,000 verified hours and DLI-administered exams. Every step, fee, and the contractor license your business needs.
If you want to work as a plumber in Minnesota, you are dealing with one of the most clearly structured state systems in the country. Plumbing licenses are issued statewide by the Minnesota Department of Labor and Industry (DLI), Construction Codes and Licensing Division. There is no county-by-county patchwork for the core license: one journeyworker license or one master license is good anywhere in the state.
This guide walks the full ladder: registered unlicensed plumber, journeyworker plumber, master plumber, and the plumbing contractor license your business needs before it can legally bid work. Every hour requirement and fee below was verified against dli.mn.gov. Fees are set by the state and change periodically, so verify current amounts with DLI before you apply.
Who Regulates Plumbing in Minnesota?
The Minnesota Department of Labor and Industry (DLI) issues all statewide plumbing credentials through its Construction Codes and Licensing Division. Applications and renewals run through iMS, DLI's online licensing system. Minnesota's plumbing rules live in Minnesota Statutes Chapter 326B, and the technical standard is the 2020 Minnesota Plumbing Code.
To legally perform plumbing work in Minnesota you must be at least 18 and either licensed by DLI, registered with DLI as a registered unlicensed plumber, or enrolled in a DLI-registered apprenticeship program. You must also be a W-2 employee of a licensed plumbing contractor or registered plumbing employer, or a licensed owner or officer of a licensed plumbing contractor. That W-2 employee requirement is written directly into the state's rules; Minnesota does not recognize casual 1099 arrangements as a path to performing licensed plumbing work for a contractor.
Step 1: Register as an Unlicensed Plumber (the Entry Point)
Minnesota's version of the apprentice level is the registered unlicensed plumber. This is how you legally log the hours that qualify you for the journeyworker exam.
Requirements and details:
- Apply online through iMS and pay the $14 initial application fee.
- You are assigned a registration number beginning with "PA."
- You may only work under the direct, at-all-times supervision of a licensed journeyworker or master plumber, within the scope your employer is authorized to perform.
- Registrations expire June 30 each year. Renewal is $19 and requires two hours of DLI-approved continuing education plus submission of your work experience verification form.
That annual work experience form matters more than most people realize. Credit toward your journeyworker exam is only granted for hours worked while you were actively registered with DLI and employed by a DLI-licensed plumbing contractor or registered plumbing employer. Work you did while unregistered generally does not count.
The alternative entry path is a DLI-registered apprenticeship program, which combines paid on-the-job training with classroom instruction and also qualifies you for the journeyworker exam on completion.
Step 2: Qualify for the Journeyworker Plumber Exam
To sit for the journeyworker exam as a registered unlicensed plumber, you need four years of recorded practical plumbing experience. Here is the detail most aggregator sites get wrong or leave out: Minnesota defines one year of practical experience as at least 1,750 hours, and no more than 1,750 hours can be credited in a single calendar year. Four years therefore means at least 7,000 hours, and you cannot compress the timeline by working overtime, the calendar-year cap makes it a true four-year minimum.
Within those four years, registered unlicensed plumbers must document:
- Water distribution system installation: 2,000 hours
- Drain, waste and vent (DWV) system installation: 2,000 hours
- Fixture installation: 1,000 hours
Experience must be certified by the licensed master plumber responsible for the work. Other qualifying routes include completing a DLI-registered apprenticeship program, holding a Minnesota restricted journeyworker or restricted master license plus two years of practical experience gained under it, or holding a current plumber's license from another state that required at least four years of practical experience and an exam. Note that no more than two years of out-of-state practical experience will be credited unless you first hold a license in that state.
Military service experience, DLI-approved plumbing coursework, and out-of-state registered apprenticeship hours can also be credited when properly certified.
Step 3: Pass the Exam and Get Licensed
Apply online to take the exam and pay the $50 exam fee. DLI administers its own plumbing exams, Minnesota does not use a third-party testing vendor for plumber licensing. Once approved, you will receive scheduling instructions. If you fail, you must wait 30 days before reapplying.
After passing, you pay for and receive your journeyworker plumber license. The license authorizes you to work statewide on interior plumbing plus exterior water service, sanitary sewer and storm sewer within the property lines, as an employee working under the direction of a master plumber.
Step 4: Master Plumber
To qualify for the master plumber exam you need one of the following:
- At least one year licensed as a journeyworker plumber (this is the standard path, four years to journeyworker, one more year to master, so about five years minimum from entry to master), or
- A current master license from another state whose requirements DLI determines are equivalent to Minnesota's, or
- A current Minnesota restricted master plumber license plus five years of verifiable experience in business as a plumbing contractor in Minnesota.
The master plumber license is the top of the individual ladder. A master can plan, superintend and perform plumbing statewide and, critically for anyone who wants to run a company, is the credential a plumbing contractor license must be built on.
License Renewal and Continuing Education
Journeyworker and master licenses expire December 31 of odd-numbered years. Renewal requires 16 hours of DLI-approved continuing education per two-year cycle, at least eight of which must relate to the State Plumbing Code. The journeyworker renewal fee is $53 (a $20 late fee applies to late renewals) and the master renewal fee is $93 ($40 late fee). All fees are set by the state and subject to change, confirm current amounts with DLI.
The Business Layer: Minnesota Plumbing Contractor License
Here is where most tradespeople hit a wall they did not see coming. A master plumber license lets you personally perform and supervise plumbing. It does not let your company contract for plumbing work. To bid, contract or offer to perform plumbing work in Minnesota, the business entity needs a plumbing contractor license under Minnesota Statute 326B.46, which requires:
- A licensed master plumber serving at all times as the company's responsible individual,
- A code compliance bond to the state of at least $25,000,
- Public liability insurance, including products liability, with limits of at least $50,000 per person and $100,000 per occurrence, plus property damage coverage with limits of at least $10,000, and
- Compliance with Minnesota workers' compensation requirements.
Bond and insurance minimums are set by statute and can change, verify against Minn. Stat. 326B.46 and DLI's current application packet.
That "responsible individual" requirement is the qualifying-agent concept in Minnesota terms: no master plumber on the license at all times, no plumbing contractor license. If your company loses its master, retirement, resignation, illness, its ability to contract for plumbing work is immediately at risk. This is exactly the problem a professionally placed qualifying agent solves. The Licensing Company places licensed masters with contractors as full-time W-2 employees, never a rented license, which Minnesota law does not permit, so the business can operate legally and continuously. Learn how it works at What Is a Qualifying Agent and Hire a Qualifying Agent.
Special Minnesota Credentials Worth Knowing
- Restricted master and restricted journeyworker licenses: valid only in cities and towns under 5,000 population, a lower-barrier path for rural plumbers, requiring four and two years of practical experience respectively.
- Certified pipelayer: a training-based card allowing exterior water service, building drain/sewer and storm sewer work within property lines, statewide, without a plumber license. It does not authorize any interior plumbing.
- Medical gas certification: required for individuals installing, maintaining or repairing medical gas systems; the company must hold a plumbing contractor license.
- Backflow prevention tester and rebuilder certifications: add-on credentials for reduced pressure zone assemblies.
- Water conditioning contractor and installer licenses: a separate track for water softener and treatment installation work.
FAQ
How long does it take to become a licensed plumber in Minnesota? A minimum of four years to journeyworker (7,000 hours with the 1,750-hour-per-calendar-year cap) and at least one more year to master. A DLI-registered apprenticeship typically runs on a similar four-to-five-year track.
How much does a Minnesota plumbing license cost? State fees verified as of this writing: $14 unlicensed plumber registration ($19 annual renewal), $50 exam application, $53 journeyworker renewal and $93 master renewal per two-year cycle. Business-side costs (the $25,000 bond premium, liability insurance, workers' comp) vary by company. All fees are set by DLI or by statute and are subject to change, verify before applying. For what it takes to get a business fully licensed and compliant, see our Consultation Packages.
Can a handyman do plumbing work in Minnesota? No. Plumbing work requires a license or a DLI registration worked under direct licensed supervision. Unlicensed plumbing is subject to enforcement by DLI, and the penalties across states keep climbing, see our roundup of 2026 contractor license law changes.
Does Minnesota license plumbing at the city level? No, the plumber license itself is statewide through DLI. Cities enforce permits and inspections locally, but your journeyworker or master license is valid everywhere in Minnesota. This is different from Minnesota HVAC, where there is no state license and cities issue competency cards, see our companion guide to Minnesota HVAC licensing.
Do I have to be an employee of a plumbing contractor to work as a plumber? Yes. Minnesota's rules require plumbers to be W-2 employees of a licensed plumbing contractor or registered plumbing employer (or a licensed owner/officer of one). The same employment principle applies at the top of the ladder: the master plumber who qualifies a contractor serves as its responsible individual, an owner, officer or bona fide employee, not an outside name on paper.
Fee, hour and insurance figures verified against the Minnesota Department of Labor and Industry (dli.mn.gov) and Minn. Stat. 326B.46 as of August 2026. Fees and requirements are set by the state and change, always verify current requirements with DLI before applying.
Ready to get your plumbing business licensed in Minnesota, or need a master plumber to qualify your company? Talk to us or learn about hiring a qualifying agent. Licensed master plumbers interested in qualifying a growing company as a full-time W-2 employee can apply here.
Disclaimer: This article is provided for educational and informational purposes only. It does not constitute legal advice, licensing guidance, or an offer of services. Licensing requirements vary by jurisdiction. For specific compliance questions, contact The Licensing Company for a confidential consultation.