Maryland Master Plumber License Requirements (2026)

The Maryland State Board of Plumbing, housed in the Maryland Department of Labor under Md. Code, Business Occupations and Professions Article §12-101 et seq., licenses plumbers statewide through a three-tier path: Apprentice Plumber, Journey Plumber, and Master Plumber, with an additional Master Plumber/Gas Fitter endorsement available for natural gas work. The path begins with apprentice registration, advances through a four-year apprenticeship of 7,500 documented hours plus the ICC Journey Plumber examination, and culminates in the Master Plumber license after two additional years of journey-level experience plus the ICC Master Plumber examination. Master Plumbers may serve as the qualifying individual for a plumbing contracting business statewide.

The Licensing Authority

Maryland State Board of Plumbing (MD Plumbing Board) is the statutory authority responsible for issuing and enforcing this license under Md. Code, Business Occupations and Professions §12-101 et seq.; COMAR 09.20. The Maryland Department of Labor houses the occupational boards that license home improvement contractors, master electricians, plumbers, and HVACR contractors statewide, adopts technical codes by reference, and conducts disciplinary proceedings.

Official portal: https://www.dllr.state.md.us/license/plumb/
Address: 1100 North Eutaw Street, Baltimore, MD 21201
Phone: (410) 230-6231

Baseline Eligibility

Eligibility begins with two baseline checks: the applicant must be 18 or older and must provide a valid Social Security Number. No Maryland residency requirement.

Good moral character

The Board reviews each applicant for good moral character. Felony and plumbing-related convictions are reviewed individually.

Background investigation

Mandatory criminal history disclosure on the application. The Board may request a full background check before issuing the license.

Experience and Education Requirements

At least four years and 7,500 hours of documented apprenticeship experience to qualify for the Journey Plumber examination, plus two additional years of journey-level experience to qualify for the Master Plumber examination has to be evidenced and confirmed. Retain payroll, tax, project, or supervisor records, since the board may audit the experience claimed.

Accepted proof of experience or eligibility

Apprentice Plumber registration and time sheets signed by the supervising master plumber
Journey Plumber license records
W-2 statements, pay stubs, or 1099 records covering the qualifying period
Approved plumbing apprenticeship completion certificate

Education substitution

Approved plumbing apprenticeship and accredited plumbing technology coursework substitute for portions of the experience requirement on a sliding scale set by Board rule.

The Licensing Examination

Testing is handled by PSI Services LLC delivering the ICC Journey and Master Plumber examinations under contract to the Maryland State Board of Plumbing. The applicant has to pass each part listed here before the credential is granted:

ICC Maryland Journey Plumber Examination — Maryland Plumbing Code, business and law — 80 questions, 240 minutes, passing score 70%
ICC Maryland Master Plumber Examination — Maryland Plumbing Code, business and law — 100 questions, 300 minutes, passing score 70%
ICC Maryland Master Plumber/Gas Fitter Endorsement Examination (optional) — 50 questions, 150 minutes, passing score 70%

Examination fee: $63 per examination paid to PSI on the day of testing.

Retake policy: Failed examinations may be re-taken by paying a new $63 fee. Each application remains valid for one year.

Financial Security and Insurance

There is no statewide surety bond tied to this credential in the cited record. Bonding can still surface at the project level — permit, license, or public-works bonds — so check before you bid.

General liability

No state-mandated general liability minimum for the master plumber license. Most counties require $300,000 to $1,000,000 liability for the contracting business.

Workers' compensation

Workers' compensation insurance is mandatory in Maryland for any business with one or more employees under Md. Code, Labor and Employment §9-402.

Additional financial requirements

No financial statement requirement.

Fee Schedule

Fee	Amount
Application (non-refundable)	$37
Examination	$63
Initial license	$37
Renewal (every 2 years)	$37

License Renewal

The Maryland Master Plumber must be renewed every 2 years. The fee to renew is presently $37. Maryland Master Plumber licenses renew every two years.

Continuing education: Continuing education is required for renewal as set by Board rule. Confirm current CE hours with the Board before renewing.

Downloadable Asset

2026 Maryland Plumber License Roadmap (PDF) — a printable step-by-step checklist for the application process.

Download the PDF roadmap →

Reciprocity Map

Maryland grants no NASCLA reciprocity for this classification.

Reciprocal State	Accepted Exam	Conditions
Virginia	Trade exam waived	Bilateral Maryland–Virginia DPOR reciprocity for active master plumbers in good standing.
Delaware	Trade exam waived	Bilateral Maryland–Delaware reciprocity for active master plumbers.
West Virginia	Trade exam waived	Bilateral Maryland–West Virginia reciprocity.

Reciprocity waives the trade examination but not Maryland-specific application requirements. The gas fitter endorsement is not automatically reciprocal and must be obtained separately.

Weighing more than one jurisdiction? The national hub compares Plumber license requirements in every state — exam, bond, fee, and experience thresholds side by side.

The Licensing Roadmap

Register as an Apprentice Plumber. File the apprentice registration with the Board before starting work. Apprentices must work under the direct supervision of a Maryland Master Plumber.
Complete the four-year, 7,500-hour apprenticeship. Document the apprenticeship hours on time sheets signed by the supervising master plumber.
Pass the ICC Journey Plumber examination at 70%. Score 70% or better on the 80-question Maryland Journey Plumber exam.
Earn two additional years of journey-level experience. Work as a Maryland Journey Plumber for at least two years after passing the journey exam.
Submit the Master Plumber application. File the Master Plumber application with experience verification, application fee, and good character documentation.
Pass the ICC Master Plumber examination at 70%. Score 70% or better on the 100-question Maryland Master Plumber exam.
Add the Gas Fitter endorsement (optional). Pass the additional ICC Gas Fitter examination to perform natural gas piping work statewide.

Common Application Pitfalls

The errors below are the ones that most frequently cost Maryland Plumber applicants time, drawn from the cited board guidance.

Skipping apprentice registration

Working as an apprentice without registering with the Board does not count toward the 7,500-hour requirement. Register before starting work.

Letting the journey license lapse before the master exam

The two years of journey-level experience must be earned while actively licensed. A lapsed journey license breaks the experience clock.

Confusing master plumber with gas fitter

The Master Plumber license alone does not authorize natural gas piping work. The gas fitter endorsement is a separate examination and must be added explicitly.

Underestimating the apprenticeship hours

7,500 hours over four years is a documented full-time commitment. Time sheets must be signed by the supervising master plumber on a regular cadence.

Skipping county registration

A Maryland Master Plumber license does not exempt the holder from county-level contractor registration. Several counties impose additional plumbing contractor rules.

Before Filing: A Checklist

Before submitting to MD Plumbing Board, the applicant should have each of the following ready:

☐ Apprentice Plumber registration with the Board
☐ Four-year, 7,500-hour apprenticeship documentation
☐ ICC Journey Plumber exam pass certificate at 70%+
☐ Two additional years of journey-level experience
☐ Master Plumber application with $37 fee
☐ ICC Master Plumber exam pass certificate at 70%+
☐ Workers compensation coverage certificate (if any employees)

Preparation Resources

The following references are cited by the regulator, used in the application process, or commonly used to prepare for the trade scope. Listed for reader convenience; CLR receives no compensation for these recommendations.

Maryland Plumbing Code (current adopted edition) — State of Maryland. Primary technical reference. Open-book at the PSI test center.
ICC Journey and Master Plumber Candidate Information Bulletins — International Code Council. Free PDFs covering exam outline, references, and sample questions.
Md. Code, Business Occupations §12-101 et seq. and COMAR 09.20 — State of Maryland. Licensing law and rules.

Other Maryland Trade Licenses

For a different Maryland credential, see these companion guides published by CLR:

Answers to Common Questions

What are the Maryland plumbing license tiers?

Maryland licenses Apprentice Plumbers, Journey Plumbers, Master Plumbers, and offers an additional Master Plumber/Gas Fitter endorsement for natural gas piping work. The path is sequential — each tier requires the prior credential.

How long is the Maryland plumbing apprenticeship?

Four years and 7,500 documented hours of work under a licensed Maryland Master Plumber, followed by the ICC Journey Plumber examination.

How do I become a Maryland Master Plumber?

Hold a Maryland Journey Plumber license, complete two additional years of journey-level experience, and pass the ICC Master Plumber examination at 70%.

Do I need a separate gas fitter license?

Yes if you perform natural gas piping work. The Master Plumber/Gas Fitter endorsement is an additional ICC examination beyond the Master Plumber license.

How often does the Maryland Master Plumber license renew?

Every two years. Renewal requires payment of the renewal fee and any continuing education the Board imposes.

Primary Sources

Regulatory requirements on this page are drawn from the official board, statute, and exam-provider materials listed below.

Verified 2026-05-12 · Next scheduled review 2026-08-10