Plumbing license requirements in Maryland: Quick Reference Table
Label | Value |
|---|---|
License type(s) | Apprentice, Journeyman, Master Plumber/Gas Fitter, Natural Gas Fitters, Propane Gas Fitter, Plumbing Inspector |
Regulating agency | Maryland State Board of Plumbing (Department of Labor) |
Required experience (Master) | 2 years as journeyman, 3,750 hours under master plumber |
Required experience (Journeyman) | 4 years as apprentice, 7,500 hours under master plumber, 32 hours backflow training |
Exam required | Yes, written exam by PSI, 70% passing |
Renewal cycle | Every 2 years |
Continuing education | 32-hour backflow prevention training for Journeyman (initial only) |
Original license fees (2025) | Master: $25, Journeyperson: $18.50, Apprentice: $12 (COMAR fees) |
Exam fees | $65 Master/Journeyman (as of Jan 2025, verify at PSI), $25 Natural Gas Fitter (verify at PSI) |
Renewal fee (2025) | Master: $31.50; Journeyperson: $18.50; Apprentice: $12 |
Apply/renew portal | |
Complete requirements & links |
Who Needs a License in Maryland?
Any individual or business that performs plumbing or gas fitting work in Maryland, except within Baltimore County or WSSC areas, must hold the appropriate state license. There is no dollar-amount threshold or exemption for small jobs. All paid plumbing and gas fitting requires licensure statewide under Plumbing license requirements in Maryland.
According to Maryland state law, all plumbing work must be performed or supervised by a licensed master plumber. Employees acting as apprentices or journeypersons must work under direct supervision. If you are a subcontractor, you must be licensed or work under a master license holder. Working unlicensed is illegal other than in exempt local jurisdictions (Baltimore County and WSSC, both of which run their own licensing programs).
No handyman, property owner, or builder exemption is stated in official sources. In summary, you cannot legally advertise or provide plumbing services in Maryland without the corresponding state license, unless your entire work is within an exempt area that issues its own licenses. Always verify local rules, as some counties reserve licensing for their own regulatory boards.
Plumbing License Types
Main Classifications
Maryland recognizes multiple license classes that define the scope of plumbing and gas fitting work you may perform. Each type carries its own training, supervision, and examination requirements. The Plumbing license requirements in Maryland describe these classes as:
Apprentice Plumber/Gas Fitter: Entry-level registration for those at least 16 years old. Apprentices may assist on plumbing or gas work but must be under direct supervision of a licensed master or, in some cases, a journeyperson. Apprentices cannot contract or work independently.
Journeyman Plumber/Gas Fitter: Workers with at least four years' apprenticeship, 7,500 hours of training under a master plumber, and 32 hours of approved backflow prevention device training. Journeymen can provide plumbing services but only under the direction and control of a master license holder.
Master Plumber/Gas Fitter: Highest licensing tier. Requires at least two years as a journeyman and 3,750 hours under a master plumber. Masters can offer, contract, perform, and supervise both plumbing and gas fitting work and are responsible for projects and employee oversight.
Gas Fitter Specialty Licenses
Apprentice Natural Gas Fitter: Must be at least 16 years old. Assists on natural gas fitting work under direct supervision of a master gas fitter or master plumber.
Journeyman Natural Gas Fitter: Completing 3,750 hours as an apprentice natural gas fitter plus approved training and exam, or holding an equivalent county/city certification. Allows hands-on gas fitting work under direction of a master.
Master Natural Gas Fitter: Applicants may qualify by holding a current master gas fitter license from Baltimore County or WSSC, or by experience and board-approved training. Masters supervise and may contract for natural gas fitting projects.
Propane Gas Fitter (Certificate): Requires NPGA-certified training (or equivalent), or prior local certification. Scope is limited to qualified propane gas fitting operations only.
Inspector Certification
Plumbing Inspector Certification: Applicants must be licensed as a master or journeyman plumber, have four years’ experience, pass a Board exam, and place their master license on inactive status. This certification allows inspection and code enforcement work.
You may hold multiple licenses if you meet the requirements. Inspector certification requires deactivation of master plumbing privileges. To comply with Plumbing license requirements in Maryland, always check that you hold the appropriate license type for your work.
How to Get Licensed in Maryland
Step-by-Step Process
To earn any level of plumbing license in Maryland, follow these concrete steps. Plumbing license requirements in Maryland are enforced by the Maryland State Board of Plumbing. Meet all prerequisites before moving to the next tier.
Meet Minimum Age
Ensure you are at least 16 years old for apprentice plumber/gas fitter or apprentice natural gas fitter levels.Register as an Apprentice
Apply to the Board for apprentice registration. You may not begin accumulating experience hours until properly registered.Complete Required Hours and Training
As an apprentice, log at least 7,500 supervised hours for the plumbing journeyman track, or 3,750 hours for natural gas. Attend board-approved 32-hour backflow prevention training if pursuing the journeyman plumber track.Apply for the License Exam
For journeyman and above, complete the PSI Candidate Information Bulletin. Submit all supporting documents, including proof of completed hours, training certificates, and a copy of your driver’s license. As of March 31, 2025, all applications must be online via the PSI portal. Mailed or faxed applications will be rejected.Schedule and Take Exam
Register for your exam through PSI. Bring required ID and documentation on exam day. You must earn at least 70% to pass the exam. Exam outlines and specifics are detailed in the PSI Board Bulletin.Submit Final License Application
After you pass, the Board will send your license application notice. Submit required proof of liability insurance and pay the applicable license fee. No bond amount is stated in official sources, but liability insurance is always required for master-level licensees offering services directly.Receive Your License
Once all documentation is complete and fees are paid, the Board issues your license. You may not contract or advertise for plumbing work until you receive your active license.
Apprentice-Level Path
Those at least 16 may register as apprentices. Apprentices may start accruing hours only after formal registration. Natural gas fitter apprenticeships follow a similar process.
Journeyman and Master Progression
Upgrading to journeyman or master plumber or gas fitter requires documented work history, completion of required training, and passing the exam for each level. Maintain documentation of all hours and coursework. The Board and PSI will require detailed proof.
Application Requirements
Each plumbing license type in Maryland has specific application requirements enforced by the State Board. Some requirements are common to all levels, while others are unique to journeyman or master applicants. Always consult the latest Plumbing license requirements in Maryland before applying.
Experience and Age
Age: Minimum 16 years for apprentice-level licenses (both plumbing and natural gas).
Experience: Journeyman plumbers/gas fitters must document four years as a registered apprentice, 7,500 hours under supervision, and 32 hours backflow device training. Master applicants must have at least two years as a journeyman and 3,750 additional hours under supervision.
Inspector: Four years' inspection or craftsman experience required, plus licensing as a master or journeyman.
Documentation: All applicants for advanced licenses must provide written evidence from previous supervisors, proof of backflow certification, and ID copies to the Board and exam provider (PSI).
Bond and Insurance
Bond: The Board does not specify a surety bond in state statutes or Board rules as of 2026.
Insurance: Master-level licensees must submit proof of liability insurance before license issuance. The statute (12-306) mandates this for all contractors contracting work in their own name. No license is given without this documentation.
Other Requirements
No citizenship or residency requirements are listed in official Board criteria.
No fingerprinting or criminal background check is mentioned in Board regulations as of 2026. This could change, so always check the Board site before applying.
Journeyman and higher applicants must complete 32 hours of approved backflow prevention training at an authorized school.
Natural Gas Fitter and Propane Gas Fitter candidates may have additional requirements based on national or local certifications.
Applicants must have all documentation ready before starting the application. Incomplete submissions will delay the review process. Strictly following Plumbing license requirements in Maryland ensures a smooth process.
Exams
For most plumber and gas fitter license types in Maryland, you must pass a Board-approved exam administered by PSI Examination Services. This requirement applies to journeyman and master levels for both plumbing and gas fitting, as well as for the plumbing inspector certificate.
The exam is a comprehensive, proctored written test covering plumbing law, code, safety, installation, materials, and relevant trade math.
No separate business law exam is listed; all major topics are combined into the single Board exam per license type.
PSI administers the test at professional test centers throughout Maryland. Computer-based testing is standard.
Passing score for all levels is 70%. The Board allows exam retakes after a mandatory one-month waiting period if you do not pass.
Exam outlines and candidate instructions appear in the official PSI Candidate Bulletin and on the board exam page.
Exact test length and number of questions for each discipline are summarized in the PSI Candidate Bulletin. Exam fees are set by PSI and must be paid directly through their portal. Confirm all exam steps with the most current Plumbing license requirements in Maryland.
Fees
The Maryland State Board of Plumbing sets all license and renewal fees by regulation. The following amounts are effective January 24, 2025. Always check the official COMAR fee schedule before payment.
Original License Fees (as of Jan 2025): Apprentice – $12, Journeyperson – $18.50, Master – $25 (COMAR .03)
Renewal Fees (as of Jan 2025): Master – $31.50; Journeyperson – $18.50; Apprentice – $12
Reactivation – $63
Reinstatement (late): $31.50 (≤30 days), $63 (31-60 days), $126 (61+ days)
Uninsured Status Certificate: $63 initial/renewal, $126 after expiration
Other documentation or transaction: Local registration assignment ID – $63; Status change – $63; Letter of good standing – $50
Exam Fees (as of Jan 2025): $65 for master/journey plumber/gas fitter, $25 for journey natural gas fitter (verify current amount at PSI)
Bond: Not specified (verify at Board requirements); liability insurance is required for contractors
Renewal and Continuing Education
All plumbing and gas fitting licenses in Maryland must be renewed every two years. Renewal is managed by the State Board through the same online portal as application and lookup.
Renewal Period: Biennial (every two years) for apprentice, journeyperson, and master levels.
Deadline: See renewal schedule in the online portal; specific due dates are not itemized in official sources but are included on your Board-issued license materials.
Late Penalties: Reinstatement fees escalate with lateness: $31.50 (≤30 days), $63 (31-60 days), $126 (61+ days); after five years, you must retake the Board exam for reinstatement.
Continuing Education: Journeyman applicants must complete 32 hours of Board-approved backflow prevention device training before initial licensure. Ongoing continuing education is not required for renewal, but the Board can require cross-connection or further safety training for certain roles.
Providers: CE and initial training must be completed at Board-approved centers (e.g., University of Florida Treeo, ASSE, USC, see COMAR).
Lapsed Licenses: If you fail to renew for five years, you will need to retake and pass the licensing exam.
Renewal notices come from the Board before expiration. Always maintain up-to-date contact information to avoid missing your renewal window and accruing additional fees. Be sure your renewal follows Plumbing license requirements in Maryland each cycle.
Reciprocity
Maryland recognizes certain licenses held in other local jurisdictions and, to a limited extent, out-of-state applicants. As of 2026, there is no broad multi-state reciprocity. However, there are two main exceptions in the Plumbing license requirements in Maryland:
Baltimore County and WSSC Jurisdictions: If you hold a master or journeyman license from Baltimore County or WSSC and have passed their equivalent exam, you may obtain the Maryland state license. You must apply, establish you are in good standing, and sometimes pass the state exam.
Equivalent Experience: Out-of-state applicants with demonstrated experience and Board-approved training may apply for licensure, but approval is at Board review and not automatic.
No other formal interstate reciprocity agreements are listed. Contractors with out-of-state credentials must apply and provide full documentation. The Board will decide if any portion of your background meets Maryland standards.
