Maryland Plumbing License: How to Become a Plumber in MD
If you live in Maryland and are looking to secure your financial future by entering a lucrative industry with lots of stability, look no further than plumbing.
The average annual salary for Maryland plumbing license holders is around $53,000, but that jumps to over $60,000 alongside industry experience. Plus, you stand to earn even more money if you start your own Maryland plumbing business.
In this guide, we’ll cover the key things you need to know about becoming a licensed plumber in Maryland.
If you’re serious about getting your Maryland plumbing license, bookmark this page and check out our other free plumbing business resources for guides, templates, and advice to set yourself up for success.
Do you need a plumbing license in Maryland?
Yes, you need a plumbing license from the Maryland Department of Labor (DOL) via the State Board of Plumbing. Working without a license can result in fines and even jail time.
With a full master plumber license from the Board, you can install, maintain, and repair the following:
- Piping, fixtures, and appliances for the supply of water
- Sanitary and stormwater drainage systems
- Systems for the disposal of wastewater and liquid waste
- Radiant-floor heating system piping
- Backflow prevention devices
In Maryland, the State Board of Plumbing also oversees the licensing of natural gas fitters.
Types of plumbing licenses in Maryland
According to the Maryland General Assembly, there are three different types of plumbing licenses given out by the DOL through the State Board of Plumbing:
| License Type | Description |
| Apprenticeship Plumber | License holder can assist a master plumber or limited master plumber license holder* in providing plumbing services, as long as they are: 1. Under the direct supervision and instruction of the master plumber or limited master plumber, and 2. In training to become a journey plumber |
| Journeyman Plumber | License holder can provide plumbing services while under the direction of a master plumber or limited master plumber. |
| Master Plumber | License holder can provide plumbing services and natural gas services. |
*A limited license holder can only provide plumbing services in a specific region of Maryland. As of 1991, however, new limited licenses are no longer issued, and license holders are grandfathered in.
Maryland plumbing license requirements
To get your license as an apprentice plumber, journeyman plumber, or master plumber, you need to meet the following requirements outlined by the DOL’s State Board of Plumbing:
| License Type | Requirements |
| Apprentice Plumber | Applicant must be at least 16 years of age and find a licensed master plumber who will direct and supervise them |
| Journeyman Plumber | Applicant must have held an apprentice plumber license for at least four years and have completed the following: • 7,500 hours of training under the direction of a licensed master plumber • 32 hours of in-class training in backflow prevention device testing Applicant must pass the written journeyman exam with a score of at least 75% |
| Master Plumber | Applicant must have held a journeyman plumber license for at least two years and have completed the following: • 3,750 hours of training under the direction of a licensed master plumber Applicant must pass the written master plumber exam with a score of at least 75% |
To work as a master plumber in Maryland, you also need to meet the plumbing insurance requirements outlined by the DOL. This includes total per occurrence coverage of at least $400,000, with at least $300,000 in general liability insurance and at least $100,000 in property damage insurance.
How do I get a plumbing license in Maryland? (steps)
To get your full plumbing license in Maryland, you need to pass through each of the preparatory license types outlined by the DOL’s plumbing board—apprentice and journeyman—to advance to master. The full process takes at least six years and includes the following steps:
- Find a licensed master plumber to work under as an apprentice and submit your apprentice application
- Work for at least four years as an apprentice, assisting your supervising licensed plumber to meet the work and learning requirements:
- 7,500 hours of supervised training
- 32 hours of in-class instruction on backflow prevention testing
- Submit your application for a journeyman plumbing license and pass the PSI exam with a score of at least 75%
- Work for an additional two years under the direction of a fully licensed master plumber to gain 3,750 hours of experience as a journeyman plumber
- Submit your application for a master plumber license and pass the exam with a score of at least 75%
- Meet the DOL’s plumbing insurance requirements with at least $400,000 of coverage: combined general liability insurance ($300,000) and property damage insurance ($100,000 per occurrence)
All forms and applications are submitted online. However, if needed, you can contact the Maryland Board of Plumbing at:
1100 N. Eutaw Street
Baltimore, MD 21201
Maryland plumbing license exam
To get your journeyman or master plumber license in Maryland, you need to pass the exam administered by the state’s testing vendor, PSI. Here’s some of the important information you should know about each test:
| Exam | Details |
| Journeyman Plumber | 100 questions 4 hours to write 75% required to pass Topics: • Plumbing fundamentals and safety (8) • Materials, uses, and specifications (6) • Traps, interceptors, and backwater valves (4) • Plumbing fixtures, fixture fittings, and plumbing appliances (4) • Water supply systems (8) • Backflow prevention (10) • Drain, waste, and vent systems (13) • Gas appliances and piping (40) • Plumbing mathematics (7) |
| Master Plumber | 100 questions 4 hours to write 75% required to pass Topics: • Plumbing fundamentals and safety (5) • Materials, uses, and specifications (6) • Traps, interceptors, and backwater valves (4) • Plumbing fixtures, fixture fittings, and plumbing appliances (4) • Water supply systems (8) • Backflow prevention (10) • Drain, waste, and vent systems (13) • Special topics (3) • Gas appliances and piping (40) • Plumbing mathematics (7) |
For more information on these exams and how the testing process works with PSI, check out the candidate information bulletin.
Does Maryland reciprocate plumbing licenses?
Reciprocal licensing agreements allow skilled trades workers with an out-of-state license to apply directly for the equivalent version in another state.
Currently, the DOL only reciprocates master plumbing licenses from the state of Delaware.
For information on how you can get your license reciprocated, check out the DOL’s plumber and gas fitter reciprocity page.
How much is a plumbing license in Maryland?
To get your full plumbing license in Maryland, you can expect to pay around $230 for the initial licensing process. Here’s a breakdown of the main fees for each stage of the licensing process:
| Licensing Stage | Fees |
| Apprentice plumber application | • $15 |
| Journeyman plumber application | • $35 |
| Master plumber application | • $70 |
| Examination | • $65 per exam |
| Renewal | Contact the DOL for more information |
Keep in mind that there are also costs associated with getting the necessary insurance coverage in order to actually work as a master plumber.
Maryland plumbing license renewal
All the licenses given out by the DOL’s State Board of Plumbing expire exactly two years from the date they are issued. The Board will give you notice of upcoming renewal about two months before expiration, including instructions on how to renew your license through the DOL’s online renewal portal.
What happens if my plumbing license expires?
If you think your Maryland plumbing license may have expired, you need to stop all work immediately. Working without a license can result in a range of penalties, from fines of $100 per day up to six months of jail time or $5,000 per violation.
Next, you can use the DOL’s license search tool to determine if your license is still valid. From there, you just need to go through the renewal process and pay all necessary late fees. In Maryland, your plumbing license can expire for up to four years before you need to go through the examination process again.
How to start a plumbing business in Maryland
After going through all of the Maryland DOL’s plumber licensing steps and gaining work experience as a fully licensed master plumber, you’re ready to take the next step in your career: starting your own plumbing business.
The state website has a Business Express page that helps you quickly progress through the administrative steps, including:
- Forming a legal entity with the Department of Assessments and Taxation
- Obtaining a Federal Tax ID Number from the IRS
- Applying for Maryland tax accounts and insurance coverage
- Obtaining any necessary licenses and permits
There are other practical steps to starting a plumbing business, too, like naming your business, figuring out how to price your services, finding the right plumbing apps, and hiring employees.
To learn more about getting a business up and running, check out our guide to starting a plumbing business.
Does a plumbing license in Maryland increase your earning potential?
Yes, getting your plumbing license in Maryland definitely increases your earning potential by providing access to lucrative work that’s regulated by the Department of Labor.
When you first get your journeyman license, you can expect to earn around $49,000 per year, but after building up a good deal of experience, you can bring in closer to $60,000. And remember—you can earn a lot more if you start your own plumbing business.