Plumbing Contractor License in Hawaii: Requirements, Qualifier, Bond and Exams

Yes.

Hawaii licenses plumbing contracting businesses statewide: plumbing contracting is specialty class C-37, Plumbing contractor, defined in the Contractors License Board's rules (HAR 16-77) under Hawaii's contractor-licensing law, HRS chapter 444.

The plumber worker license is a separate credential: the state's application form states that the electrician's or plumber's license does not allow one to contract to perform electrical or plumbing work — a contractor's license pursuant to 444, HRS is required.

So the C-37, not the Journey Worker or Master Plumber license, is what your business contracts under.

Contractor licensing runs through the Contractors License Board (DCCA Professional and Vocational Licensing Division), and its rules (HAR 16-77) define the classes.

For a plumbing business the class is C-37, Plumbing contractor, plus six sub-classifications: C-37a sewer and drain line, C-37b irrigation and lawn sprinkler systems, C-37c vacuum and air, C-37d water chlorination, C-37e treatment and pumping, and C-37f fuel dispensing.

HVAC contracting sits alongside it as class C-52, Ventilating and air conditioning contractor, issued by the same board.

Hawaii calls its qualifier the Responsible Managing Employee (RME) — the role Florida and Tennessee call a qualifying agent, and Arizona and Louisiana a qualifying party.

A contracting company must employ a licensed individual designated as its RME: the RME must be at least 18, have 4 years of supervisory experience within the past 10 years, and pass the exam.

The requirement rests on the company employing a qualified RME; our research does not state that the owner must personally serve as the RME, so confirm your ownership structure with the board before you file.

The Hawaii contractor exam has two parts: Part I covers business and law, and Part II covers trade knowledge in the classification — for a C-37 application, plumbing.

A grade of 75% is the minimum passing grade on each part.

Prometric administers the exams: the board approves your application first, then you register and pay exam fees to Prometric.

The board pages we read did not state current Prometric exam fees, so confirm those with the board or Prometric before you budget.

Hawaii sets minimum liability insurance for contractors: $100,000 bodily injury per person, $300,000 per occurrence and $50,000 property damage, plus workers' compensation.

Bonds work differently — the rules set no fixed bond amount.

As proof of financial integrity, the board may require the applicant to post a surety bond as a condition for licensure, and it can waive the bond after at least one year, so whether a bond applies to you rests with the board.

The application costs a $50 non-refundable fee, and the entity application form we read (October 2025) lists the license fee at $260 plus a recovery fund fee of $74 or $148.

Licenses renew on or before September 30 of each even-numbered year.

The research we read lists no renewal fee, and our reading of the contractor rules (HAR 16-77) found no continuing-education hours for contractors or RMEs — both are gaps in our research, not board statements, so confirm current fees and any continuing education with the board before you budget or renew.

Our research found no reciprocity provision in the Hawaii contractor rules we read — an absence from our reading, not a board statement — so an out-of-state plumbing company should plan to apply and pass both parts of the Hawaii exam.

Applicants may request board approval to take the licensing examination out of state.

Because agreements change, ask the board whether any reciprocity now exists before you assume none does.

If your RME dies, leaves the company or becomes disabled, two clocks start: the entity must notify the board within 60 days, and submit an application to qualify a new RME — or place the license on inactive status — within 90 days, or the license is forfeited.

For a plumbing shop whose qualification hangs on one person's license, treat those windows as a standing hiring risk: know your next qualifier before your current one gives notice.

Yes.

Hawaii's contractor-licensing law exempts any project or operation whose aggregate contract price for labor and materials is not more than $1,500; above that amount, the license requirement applies.

The exemption does not hold where a building permit is required for the work, and it does not protect a job split into smaller contracts to evade the law — so check how your small service work and your permit-triggering jobs are treated before you bid.