Getting a plumbing license is a multi-year process. The exact path varies by state but the broad sequence is the same across the country: finish high school, pick a state, start an apprenticeship under a licensed plumber, log thousands of hours of supervised work, take and pass a journeyman exam, get the journeyman license, then optionally work toward master plumber after another two to four years. The median plumber in the US now earns around $62,970 per year per the Bureau of Labor Statistics, and the field is projected to grow 4% from 2024 to 2034. The license is what unlocks the upper half of that wage curve and the option to eventually run your own business.
The steps below walk through the journey from no experience to a fully credentialed journeyman plumber, with notes on the master plumber path that comes after.
Finish High School
Almost every state requires a high school diploma or GED before you can register as a plumbing apprentice. The reasoning is practical rather than ceremonial. The trade involves math (pipe sizing, pressure calculations, slope and grade), code reading (the IPC or UPC depending on jurisdiction), and a fair amount of written documentation on permits and invoices. Without the basic reading, math, and writing fluency that a diploma represents, the apprenticeship gets harder than it needs to be.
Vocational high schools with plumbing programs give you a head start, since the coursework can sometimes be credited against the hours required for the journeyman license later. Up to 50% of required hours can be offset by approved trade-school coursework in many states.
Choose Your State
State variation in plumbing licensure is more significant than most prospective plumbers realize. Three things change from state to state.
The hours required vary widely. Texas requires 8,000 hours of supervised work for the journeyman license. Pennsylvania requires four full years at 40 hours per week plus 576 classroom hours. Colorado allows a separate residential plumber license at the two-year mark before the full journeyman license at four years. A handful of states require closer to 4,000 hours.
The exam content varies. Some states use the International Plumbing Code as the reference. Others use the Uniform Plumbing Code. A few use a state-specific code. The exam itself is typically a written multiple-choice test of three to four hours, with some states adding a practical component.
Reciprocity is rare. Roughly 10 states have formal reciprocity agreements with neighbors, where a journeyman license in one state qualifies you to skip the exam in another. Most states require you to retake the exam if you move. Choosing where you want to spend the bulk of your career before you start the hour-logging process saves the most time.
Start an Apprenticeship
An apprenticeship is the only legal path to enough hours in most states. Three avenues to find one.
Union apprenticeships through the United Association (the UA) are the most structured option. Five-year programs with paid on-the-job training and classroom instruction, typically with health insurance and retirement benefits built in. The UA local hall is the first call. Open enrollment windows vary by local.
Non-union contractor apprenticeships work the same way but are run directly by a plumbing contractor under a state-registered apprenticeship program. Plumbing-Heating-Cooling Contractors Association (PHCC) chapters often coordinate these. The pay scale is similar to union, the benefits structure varies.
Trade school plus apprenticeship is the third path. Enroll in a community college or trade school plumbing program (typically 12 to 24 months), graduate, then sign on with a contractor as an apprentice. The trade-school hours offset some of the required field hours, which compresses the total timeline.
Whichever path you pick, the master plumber or journeyman you work under matters more than the program name on paper. Apprenticeship is on-the-job learning. A great mentor accelerates the career by years. A bad mentor stalls it.
Log the Hours
The bulk of the journeyman timeline is logged hours under direct supervision. Two to four years of full-time work covers the requirement in most states. The hour count typically tracks at 2,000 hours per year for a 40-hour-week schedule with two weeks of vacation, which is why most state requirements land in the 4,000 to 8,000 hour range across one to four years.
Keep the documentation tight from day one. The state licensing board will require verified hours from your master plumber when you apply for the journeyman exam, and reconstructing that record from memory three years in is painful. A simple spreadsheet logging start date, end date, hours per week, and the master plumber who supervised the work is enough. Some states require a specific log form filled out and signed weekly or monthly.
Most states also require classroom hours alongside the field hours. Pennsylvania's 576 hours is on the high end. Most states land in the 200 to 600 classroom-hour range. The classroom hours cover code, math, and theory that the field work alone does not teach.
Pass the Exam
Once the hours and classroom requirements are met, you apply to sit for the state journeyman plumbing exam. The application is paperwork-heavy: verified hour logs, classroom transcripts, the master plumber's sign-off, sometimes an FBI background check, sometimes character references, and the exam fee that typically lands between $50 and $250.
The exam itself is three to four hours of multiple choice testing on plumbing code, math, materials, and installation methods. Some states add a practical component where the candidate demonstrates pipe joining, soldering, or fixture installation. The pass rate is typically 60 to 70% on the first attempt, which means meaningful preparation is required even after a full apprenticeship. Plan on two to four weeks of focused review using state-specific exam prep books and practice tests.
Standard test-day discipline applies: solid sleep, normal breakfast, arrive early, read every question fully, do not rush. Most candidates who fail the first time pass on the second attempt.
Apply for the License
Passing the exam is not the license. The license is issued after you submit the post-exam application, pay the licensing fee (typically $100 to $300 depending on state), and clear any background or insurance requirements the state board has.
Most states issue the license within 2 to 6 weeks of the application clearing. The license includes a unique number that goes on every permit you pull and every invoice you issue. The license is the legal credential that unlocks unsupervised work, the right to pull permits in your own name on residential work, and the wage tier above apprentice pay.
The license requires annual renewal. Renewal involves a fee and, in most states, documented continuing education hours covering code updates. Plumbing codes update on a three-year cycle in most jurisdictions, and the continuing education requirement keeps your knowledge current.
The Master Plumber Path
The journeyman license is the working credential. The master plumber license is the business credential. After two to four years of journeyman experience (the exact requirement varies by state), you become eligible to sit for the master plumber exam.
The master exam is longer, harder, and more management-focused than the journeyman exam. Code knowledge is assumed at this point. The new content covers plumbing design, system layout, business and contract law, permit and inspection processes, and supervisor responsibilities. The master license unlocks the right to operate your own plumbing business, hire and supervise other plumbers, and stamp plumbing plans for permit approval.
Master plumber is the credential most career plumbers eventually pursue. The wage and ownership opportunities at the master tier are meaningfully wider than at the journeyman tier, and the business-side career options open up. Companion reads on the next steps: a guide to the plumbing interview questions that come during the journeyman job hunt, and the playbook for buying a plumbing business for masters thinking about the ownership path.
On the Truck
The plumbing license process is long, predictable, and worth the time. The hour requirements feel steep on day one but become almost background after the first year of apprenticeship, and the journeyman license is the credential that genuinely changes the wage curve and the autonomy of the work.
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