Kentucky Master Plumber Requirements

Experience Requirement After Journeyman

To qualify for the master plumber exam in Kentucky, you must hold an active journeyman plumber license and have at least two years of post-licensure employment under a licensed master plumber's supervision. That experience must fall within the five years immediately preceding your application — older work does not count.

This means you cannot let your journeyman license lapse and then try to claim old work history. If you spent time on inactive status or working outside of plumbing, only the years you actually practiced under a master's oversight during the most recent five-year window satisfy the requirement.

Exam Registration

Register using Form PLB-3, the same exam registration form used for the journeyman level. Submit it to the DHBC Licensing Branch in Frankfort at least three weeks before the scheduled exam date. The master exam fee is $150 (non-refundable, payable to the Kentucky State Treasurer), and you must include a current passport-sized color photograph.

Exams are held quarterly — February, May, August, and November — at testing centers across the state. Check-in begins at 7:30 AM with testing starting at 8:00 AM.

What the Master Exam Covers

Unlike the journeyman exam, the master exam is written only — there is no practical portion. You have 2.5 hours to complete a test covering:

• Advanced code application and system design
• Project management and supervision requirements
• Business law provisions under KRS Chapter 318 and 815 KAR Chapter 20

You may bring a tabbed copy of the Kentucky Plumbing Code. The passing standard is higher than the journeyman level: 80% overall with a minimum of 75% on each section. The same one-year retake rule applies — if you do not pass within a year of your first exam notice, your application voids completely and you start over with new fees and paperwork.

Activating the Master License

After passing, submit Form PLB-1 (Master Plumber License Application) with:

• A $250 license fee
• Proof of general liability insurance of at least $250,000, with the certificate naming the DHBC as certificate holder
• Proof of workers' compensation and unemployment insurance compliance, if you employ anyone

The insurance requirement is not optional and not deferrable. Your license will not activate without the ACORD certificate on file. Some Louisville and Lexington projects require $1,000,000 or more in coverage, but the state minimum is $250,000.

What the Master License Unlocks

The master plumber credential is the highest individual technical tier in Kentucky. It authorizes you to:

• Assume responsible charge, direction, and supervision of journeymen and apprentices
• Pull plumbing construction permits directly from the state Division of Plumbing
• Serve as the technical "qualifier" for a plumbing contracting business entity

This is where the licensing system shifts from technical skill validation to business authority. A master plumber employed by a contracting firm oversees all work performed under the company's permits. A master who wants to run their own operation must take the additional step of registering a business entity and filing a Letter of Representation with the DHBC.

The Contractor Step

Holding a master license does not automatically make you a contractor. The contracting entity — whether an LLC, corporation, or sole proprietorship — must be registered with the Kentucky Secretary of State, must employ or be owned by an active master plumber as its designated qualifier, and must carry a $10,000 surety license bond on top of the insurance already required.

Every form, fee, and compliance step from journeyman through contractor setup is covered in the Kentucky Plumber License Guide.

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