How to become a licensed plumber, from apprentice to master

There is no single national plumbing license. Each state sets its own rules, and some cities and counties add theirs. The path often follows a similar shape, though: register as an apprentice, log years of supervised hours, pass a journeyman exam, add more experience, pass a master exam, and license the company before you contract with the public. This guide walks through each step as it usually works, using three state boards we read in October 2026 as examples. Treat this guide as general information, not legal advice. If it and your state board's posted rules ever differ, follow the board.

For a sense of the trade's pay, the Bureau of Labor Statistics reports a median annual wage of $63,800 for plumbers, pipefitters and steamfitters in May 2025. That is a wage for employed workers. It does not measure what a shop owner takes home.

Who issues a plumbing license?

In most of the country your state does, and sometimes your city or county as well. The SBA's table of federally licensed activities covers things like aviation, alcohol, firearms and commercial fishing. Plumbing is not on it. The SBA tells owners to research their own state, county and city rules, because requirements depend on the activity and the location.

BLS describes the common pattern: plumbers need a license in most states and in some localities, and those rules often call for 2 to 5 years of experience and a passing exam score before a plumber may work independently. BLS also notes that some states license pipefitters and steamfitters, and that a special license may be needed to work on gas lines.

Start with our state-by-state startup pages, which name the licensing agencies in each state. Then go to the plumbing board's own website. Boards post the current application, fees, exam vendor and renewal rules there, and those change more often than any outside summary, including this one.

What are the usual plumbing license levels?

Titles differ by state. Texas and Michigan both use a ladder of the shape shown in the table. Your state may merge two levels, add a limited license, or use other names.

Texas shows how many categories one state can carry. Its State Board of Plumbing Examiners lists Tradesman Plumber-Limited, Journeyman Plumber, Master Plumber and Plumbing Inspector licenses; registrations for apprentices, drain cleaners and residential utilities installers; and endorsements for medical gas piping, water supply protection and multipurpose residential fire sprinklers.

How do you get the experience hours?

Every path runs through supervised work. BLS says most plumbers come up through an apprenticeship lasting four or five years. Apprentices typically log about 2,000 paid hours on the job each year, along with technical instruction in safety, local plumbing codes and blueprint reading. There are two common ways in.

• A Registered Apprenticeship. The Department of Labor's Registered Apprenticeship model pairs a paying job and a mentor with raises as your skills grow, classroom instruction, and a credential that is portable and nationally recognized. Programs are approved by the DOL or a State Apprenticeship Agency. The DOL's Apprenticeship Finder searches openings by career and location.
• A job with a licensed shop. Texas and Michigan both let you build the hours as a registered apprentice working under licensed plumbers, without a formal apprenticeship program (Texas then asks for a short approved course, below). Michigan's journeyperson licensure map starts with a job at a licensed plumbing contractor and an apprentice registration, followed by 6,000 hours over at least three years.

Some boards give formal programs extra weight. Texas asks journeyman candidates for 8,000 hours of plumbing experience plus either a 48-hour training course the board approves or enrollment in a program approved by the DOL Office of Apprenticeship. Its master license normally requires two years as a licensed journeyman, or one year for someone who finished a DOL-approved program.

Records matter even in states that verify experience differently. California's contractor board, for example, wants experience claims verified by someone with firsthand knowledge of your work, such as an employer, foreman, fellow journeyman, building inspector or homeowner. Pay stubs and a contact list from every employer make that easy years later.

What is on a plumbing license exam?

The exam is where your code study pays off, and the format depends on the state:

• Michigan requires journeyperson applicants to pass a written exam and a hands-on practical skills exam on a single application, according to LARA's plumbing licensing page. Applications are valid for one year, and passing scores do not carry over to a new application.
• California splits its plumbing contractor (C-36) trade exam into five sections in the CSLB study guide for exams on or after March 1, 2025: planning and estimating (about 22%), underground and rough systems (22%), finish plumbing (20%), service, repair and remodel work (19%), and safety (17%). It is closed book and multiple choice. Candidates must also pass CSLB's Law and Business exam on business management and construction law, and the exam FAQ allows 3.5 hours for each test.

Before you study, get your board's candidate information: which vendor gives the test, which code edition it covers, whether code books are allowed, and whether a practical portion applies. California's guide, for instance, lists the 2025 California Plumbing Code among its references. Study the edition your exam names.

Do you need a separate license to run a plumbing company?

Usually, yes. The personal license shows you can do the work. A contractor license, or a master formally tied to the company, is what lets the business sell that work to customers. Three states show three versions of the same idea.

• Michigan. A plumbing contractor applicant must either hold a master plumber license or employ a master plumber as its representative, under MCL 339.6111, and must pass an exam. LARA says the contractor license will not be issued without master representation, and its master licensure map adds that a master may represent only one plumbing contractor at a time. Michigan's master license itself requires 4,000 hours of work as a licensed journeyperson during the two years right before you apply.
• Texas. A Responsible Master Plumber is responsible for the general supervision and management of plumbing work done under contracts secured under that license, whether employees or subcontractors do the work. An RMP can serve only one company at a time, and the company's service vehicles must show the company name and the RMP's license number.
• California. CSLB licenses plumbing companies under the C-36 Plumbing Contractor classification. Under CSLB's experience rules, an applicant needs at least four years of experience in the classification to take the exam, credited only for work at the journeyman level or as a foreman, supervising employee, contractor or owner-builder. Technical training, apprenticeship or schooling can stand in for as many as three of those years, but at least one year has to be hands-on work.

If you own the company but someone else holds the master license, your right to operate depends on that person. Ask your board how long you have to name a new qualifier if they leave, and plan for it before it happens.

Licensing also reaches your marketing. Where a state or city expects a license number on trucks, ads or your website, put it there from day one and keep it current when the qualifier changes.

What insurance and bonds come with a plumbing license?

Some boards want proof of coverage before they issue or renew a company license, and what they ask for varies:

• Texas requires a Responsible Master Plumber to maintain at least $300,000 of commercial liability insurance and to send a certificate of insurance with the application.
• California sets the contractor's bond at $25,000, a figure in place since January 1, 2023. Per CSLB's bond requirements, the bond has to be on file before an active license is issued or renewed. CSLB says it is there for customers damaged by defective work or other license-law violations, and for workers who were not paid what they were owed. A second $25,000 bond, called the bond of qualifying individual, comes into play when the person qualifying the license is a responsible managing employee, or an officer whose share of the corporation's voting stock is below 10%. Before issuing the license, CSLB also wants a workers' compensation certificate or an exemption if you have no employees, and LLC liability insurance if that applies.

Before you call an agent, read how surety bonds work and what contractor insurance covers. Then you can ask for what the board requires and what property managers and general contractors will ask to see on a certificate.

Which federal rules apply to licensed plumbers?

The license is a state matter, but a few federal programs touch plumbing work.

• EPA lead-safe renovation (RRP). EPA's guidance for contractors names plumbers among the trades covered. Paid work that disturbs paint in houses, apartments or child-occupied facilities such as schools and child care centers built before 1978 generally requires certification. Small jobs fall outside the rule: up to six square feet of painted surface per room indoors, or up to 20 square feet outdoors. Replacing windows, or demolishing painted surfaces, is covered no matter the square footage. Opening a painted wall to reach a drain in an older house can cross that line. Firms apply online for EPA firm certification, which runs five years and applies to sole proprietors too, and every covered job needs a certified renovator assigned to it. Some states, among them Georgia, North Carolina and Wisconsin, run their own EPA-authorized programs in place of the federal one. EPA notes that a firm working in more than one state may need both EPA and state certification.
• Lead-free materials. Under the Safe Drinking Water Act, EPA explains that materials used to install or repair plumbing that supplies drinking water must be lead free. The limit is 0.2% lead for solder and flux, and a weighted average of 0.25% lead over the water-contact (wetted) surfaces of pipes, pipe and plumbing fittings, and fixtures.
• OSHA safety training. OSHA's Outreach Training Program offers a 10-hour construction class aimed at workers and a 30-hour class suited to supervisors. OSHA calls the program voluntary and says finishing it does not satisfy the training its standards require. OSHA also says some states and municipalities, among others, may make the training a condition of employment.

Our guide to starting a plumbing business covers trench safety and 811 calls for sewer and water line work.

How do you keep a plumbing license active?

A plumbing license has to be renewed, and in Texas and Michigan renewal depends on continuing education as well as fees. The Texas board says its licenses renew every year and that every licensee must complete six hours of continuing professional education to be eligible to renew. Its endorsements renew every three years, and medical gas piping endorsement holders need at least two hours of continuing education. Michigan's licensure maps make continuing education a condition of renewing a plumbing journeyperson license.

Letting a license lapse can cost more than a late fee. The Texas board will not renew a license that has been expired for more than two years. Reinstating it means registering as a Plumber's Apprentice again and passing the applicable exams under the current eligibility rules. In Michigan, any lapse in journeyperson licensure during the two years before a master application means the applicant does not meet the experience requirement.

Track every renewal date on your team, including the master who qualifies the company. A lapsed license can sideline a plumber, or the company that plumber qualifies. A shop CRM that stores license numbers, expiration dates and insurance certificates next to each employee's record, with reminders, takes this off your memory. We build that kind of custom CRM for service companies, starting with our own.

Can you move a plumbing license to another state?

Not automatically. Some states sign reciprocity agreements, and others give an out-of-state license some credit toward their own exams. Two examples:

• California has a reciprocity program with Arizona, Louisiana, Mississippi, Nevada and North Carolina. The classification must appear on that state's reciprocal list, and you must have held an active license in good standing there for the previous five years. Reciprocity may waive the trade exam, though CSLB keeps the right to require it, and you still take the business law portion.
• Texas lets someone currently licensed as a journeyman or master plumber in another state sit for its journeyman exam without first registering as a Texas apprentice, and it waives the 48-hour training course for them. The 8,000 hours of experience still apply. A master plumber licensed in another state can sit for the Texas master exam if they first held a journeyman license for two years or more, or for one year plus a completed DOL-approved apprenticeship program.

If you plan to move, or to take work across a state line, ask the new state's board in writing what it will accept. Get the answer before you sign a lease or bid a job.

The licensing path, step by step

1. Look up your state's plumbing board on our state pages, then read the board's license categories and current application.
2. Get hired by a licensed plumbing company or accepted into a Registered Apprenticeship, and register as an apprentice right away.
3. Log hours and classroom training, with records your board will accept.
4. Apply for and pass the journeyman exam, written and practical where required.
5. Work as a journeyman for the time your state requires, and keep up with continuing education.
6. Pass the master exam.
7. Form the company, buy the insurance and bond your board requires, and apply for the contractor license with your master as qualifier. Check city registration too.

Once the license is on the wall, the work shifts to finding customers who call you directly. Our plumbing industry page walks through the website pages, call handling and CRM records that fit a plumbing shop, and the start a company hub has the rest of the setup guides. When your opening date is set, get a free launch plan for the website, phone line and CRM you will open with.

Frequently asked questions