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

Statewide.

Oklahoma licenses plumbers and plumbing contractors across the state through the Construction Industries Board (CIB) under the Plumbing License Law of 1955, and the plumbing credentials run registered apprentice, journeyman (unlimited or residential) and contractor (unlimited or residential).

The contractor license is the one a plumbing business contracts on: a journeyman may not contract or furnish labor and materials on their own and must be employed and supervised by a licensed plumbing contractor.

One boundary matters for how you set the company up: Oklahoma does not require general contractors to hold a state license, while trade contractors in mechanical, plumbing and electrical do need state licenses.

The Oklahoma Construction Industries Board (CIB) issues the plumbing contractor license in two classes: unlimited or residential.

The journeyman license underneath carries the same unlimited-or-residential split, and registered apprentice sits at the entry rung.

Our research captured the class names the license law sets out but not the scope line the CIB draws between unlimited and residential plumbing contracting, so confirm which class fits the work you bid before you apply.

The qualifier is the contractor licensee.

An applicant meets the journeyman requirements plus one more year of experience.

The journeyman requirements are at least 18 years old and three years of plumbing experience while employed by a licensed plumbing contractor, with school substituting part of that — for example, a 1,000-hour approved program counts for two years.

Two consequences matter when you staff the business.

First, a journeyman, however skilled, cannot contract or furnish labor and materials on their own: contracting is what the contractor license is for.

Second, apprentice hours feed the pipeline only if the paperwork is current — Oklahoma plumbing apprentices must register with the CIB every year, with a licensed contractor or approved school instructor signing each year's application, for their hours to count toward licensing, unless the experience was lawfully obtained while exempted.

Two portions.

A plumbing contractor applicant must pass both the business-and-law portion and the trade portion.

The pass mark is the same across the CIB's plumbing exams: an examinee must make 75% or more on each part.

The out-of-state route the rules set out: a plumber from a state with no Oklahoma reciprocity agreement may apply for exam equivalency if the Board has approved that jurisdiction's exam, and the contractor applicant still has to pass Oklahoma's business-and-law section.

Our research did not capture the vendor, format or fee for the current plumbing exams, so check those with the CIB before you book.

Active plumbing contractors keep two financial filings with the Board: a $5,000 corporate surety bond payable to the Board — the rules also allow $5,000 in cash or a certificate of deposit in its place — and general liability insurance of at least $50,000.

These are standing requirements for an active contractor, not one-time application paperwork: the rules say each active plumbing contractor must maintain the bond.

The plumbing contractor fees are a $30 application, a $300 initial license and a $200 annual renewal, with a $100 late fee, per the CIB plumbing rules effective October 1, 2024.

Renewal runs on a birthday calendar: the CIB's mechanical and plumbing licenses last up to one year and expire on the last day of the licensee's birth month.

Renewal also carries continuing education — journeymen and contractors need six hours of approved CE every three years (36 months).

The qualifier's own journeyman license carries separate fees: $25 to apply, $50 for the initial license and $75 to renew.

Narrowly, and at the journeyman level.

The agreement our research verified is with Arkansas: the CIB signed a multi-year plumbing reciprocity agreement with the Arkansas Committee of Plumbing Examiners effective October 21, 2024, under which eligible licensed plumbers — a license held at least one year and a state exam passed — can get an unlimited journeyman license without the journeyman test, and it is not automatic.

Note the level: the agreement's benefit is the journeyman license, and our research does not describe contractor-level plumbing reciprocity beyond exam equivalency.

Within that equivalency route — open to a plumber from a state with no Oklahoma reciprocity agreement, where the Board has approved the jurisdiction's exam — the contractor applicant still takes and passes Oklahoma's business-and-law section.

The CIB announced the Arkansas agreement, so treat the Board as the authority on its current terms.

Start with what the plumbing rules our research read do not say: whether one plumbing contractor licensee may qualify more than one firm, and any deadline for replacing a departed contractor licensee, was not found in the plumbing rules.

The CIB's mechanical rules do contain a one-firm rule for mechanical contractors, but our research did not find a plumbing equivalent, so do not assume either way — ask the Board before you structure two companies around one qualifier, or before riding out a gap without a contractor licensee.

The dependable path is internal: the contractor application takes the journeyman requirements plus one more year, and a candidate's apprentice hours only bank toward that if they registered with the CIB every year, unless the experience was lawfully obtained while exempted.

No. In Oklahoma, medical gas is a mechanical category, not a plumbing one, and the CIB lists it as journeyman only: it requires certification under the current NFPA 99 standard or an approved medical gas certification.

If your plumbing company plans to bid work that includes medical gas systems, ask the CIB which license combination covers that scope before you commit to the bid.