Montana Plumber License Requirements (2026) | Official Board of Plumbers Guide

The Montana Board of Plumbers, part of the Department of Labor and Industry Business Standards Division, licenses plumbers statewide under Montana Code Annotated Title 37 Chapter 69. The Board issues Apprentice, Journeyman, and Master Plumber credentials. All plumbing work performed for hire must be done by a licensed plumber, and Montana enforces the Uniform Plumbing Code (UPC) as adopted by the State Building Codes Division. Master Plumbers may own and operate plumbing contracting businesses; Journeymen work under the supervision of a Master.

The Licensing Authority

Authority over this credential rests with Montana Department of Labor and Industry — Business Standards Division (MT DLI), which issues and polices it under Montana Code Annotated Title 37 (Professions and Occupations) and Title 39 Chapter 9 (Independent Contractor Central Unit). The Montana Department of Labor and Industry administers the Construction Contractor Registration program, the Independent Contractor Exemption Certificate, and houses the State Electrical Board and Board of Plumbers that license individual electricians and plumbers statewide.

Official portal: https://dli.mt.gov/business-standards
Address: 301 South Park Avenue, 4th Floor, PO Box 200513, Helena, MT 59620
Phone: (406) 444-3555

Baseline Eligibility

The applicant must be at least 18 years of age and possess a valid Social Security Number. No Montana residency requirement.

Good moral character

The Board of Plumbers reviews prior discipline and felony convictions individually.

Background investigation

Applicants disclose criminal history on the application. No fingerprint background check is required.

Experience and Education Requirements

The experience bar is four years and 8,000 hours of plumbing work under a Montana-licensed Master Plumber for Journeyman eligibility, plus two additional years as a licensed Journeyman before Master eligibility, and it must be backed by verifiable records — typically payroll, tax, project, or supervisor documentation covering the claimed period.

Accepted proof of experience or eligibility

Board of Plumbers Experience Verification Affidavit signed by each supervising Master Plumber
W-2 statements or certified payroll records covering the qualifying period
Montana Registered Apprenticeship completion certificate (where applicable)

Education substitution

Completion of an approved plumbing apprenticeship program counts toward the 8,000-hour requirement on a sliding scale set by Board rule.

The Licensing Examination

The exam, administered by PSI Services LLC (under contract to the Montana Board of Plumbers), breaks into the parts shown below — all must be passed before licensure:

Montana Journeyman Plumber Examination — Uniform Plumbing Code and Montana law — 80 questions, 240 minutes, passing score 70%
Montana Master Plumber Examination — UPC, theory, business and law — 100 questions, 300 minutes, passing score 75%

Examination fee: $85 examination fee paid to PSI per attempt.

Retake policy: Failed examinations may be retaken by paying a new $85 fee. Applications remain active 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

The Board of Plumbers does not mandate a general liability minimum for individual plumbers. Most commercial jobs contractually require $1,000,000/$2,000,000.

Workers' compensation

Mandatory under Title 39 Chapter 71 MCA for any plumbing business with employees.

Additional financial requirements

No financial statement requirement for individual Journeyman or Master licensure.

Fee Schedule

Fee	Amount
Application (non-refundable)	$100
Examination	$85
Initial license	$120
Renewal (every year)	$120

License Renewal

The Montana Master Plumber / Journeyman Plumber must be renewed every year. The fee to renew is presently $120. Montana plumber licenses renew annually through the Board of Plumbers.

Continuing education: Continuing education each renewal cycle as set by Board administrative rule, including UPC update hours.

Downloadable Asset

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

Download the PDF roadmap →

Reciprocity Map

Montana grants no NASCLA reciprocity for this classification.

Reciprocal State	Accepted Exam	Conditions
North Dakota	Journeyman exam waived	Bilateral reciprocity for active Journeyman Plumbers in good standing.
South Dakota	Journeyman exam waived	Bilateral reciprocity for active Journeyman Plumbers.
Wyoming	Journeyman exam waived	Bilateral reciprocity for active Journeyman Plumbers.

Montana maintains bilateral Journeyman plumber reciprocity with neighboring states. Master reciprocity is reviewed case by case.

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. Enroll with the Board of Plumbers as an Apprentice and begin working under a Master Plumber.
Log 8,000 hours over four years. Document every hour with your supervising Master Plumber.
Apply for the Journeyman examination. Submit the application, experience affidavits, and fee to the Board of Plumbers.
Pass the PSI Journeyman examination at 70%. Score 70% or better on the 80-question UPC-based examination.
Work two years as a Montana Journeyman. Accumulate two years of licensed Journeyman experience before Master eligibility.
Apply for and pass the Master Plumber examination. Score 75% or better on the 100-question Master examination.
Renew annually. The Board issues the license and requires annual renewal with continuing education.

Common Application Pitfalls

The following pitfalls summarize the issues most likely to delay, return, or derail a Montana Plumber application based on the published board instructions and source materials cited on this page.

Undocumented apprentice hours

The Board rejects applications without signed affidavits from each supervising Master Plumber. Keep contemporaneous records.

Skipping the Journeyman step

Master Plumber requires two years of licensed Journeyman experience. Direct-entry to Master is not allowed.

Studying the wrong code

Montana uses the UPC, not the IPC. Candidates who study from the wrong codebook fail the Journeyman examination.

Forgetting CCR or ICEC

The individual Master Plumber license does not authorize running a contracting business without DLI registration.

Missing annual renewal

Working under a lapsed license triggers disciplinary action and may void contracts.

Before Filing: A Checklist

Have each of the following squared away before the packet goes to MT DLI:

☐ 8,000 hours and four years of documented experience
☐ Signed experience affidavits from supervising Master Plumbers
☐ Journeyman exam application with fee
☐ PSI Journeyman exam pass at 70%+
☐ Two years of Montana Journeyman experience
☐ Master exam application and PSI exam pass at 75%+
☐ Continuing education compliance for annual renewal

Preparation Resources

These materials are drawn from the regulator's own citations and the references applicants commonly use to prepare. CLR receives no compensation for listing them.

Uniform Plumbing Code (current Montana-adopted edition) — IAPMO. Primary technical reference. Open-book at the PSI test center.
Montana Code Annotated Title 37 Chapter 69 — State of Montana. Plumber licensing statute.
Montana Board of Plumbers Administrative Rules — Montana DLI. Procedural rules for licensing and discipline.

Other Montana Trade Licenses

Looking at a different trade? CLR also publishes these Montana licensing guides:

Answers to Common Questions

What plumbing code does Montana enforce?

Montana adopts the Uniform Plumbing Code (UPC) through the State Building Codes Division. The Board of Plumbers examinations are UPC-based.

How long does it take to become a Master Plumber in Montana?

Four years to reach Journeyman (8,000 hours) plus two additional years as a licensed Journeyman before Master eligibility.

Does Montana reciprocate plumbing licenses?

Yes. Montana has bilateral Journeyman reciprocity with North Dakota, South Dakota, and Wyoming.

How often does the license renew?

Annually. Renewal requires continuing education each cycle including UPC updates.

Do I need a business registration on top of the Master license?

Yes. To run a plumbing contracting business you also need DLI Construction Contractor Registration or an Independent Contractor Exemption Certificate.

Primary Sources

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

Verified 2026-05-27 · Next scheduled review 2026-08-25