Montana — plumbing code & licensing
Verified
The code
| Code family | UPC |
| Edition in force | Uniform Plumbing Code, 2024 Edition, adopted and incorporated by reference with appendices and amendments at ARM 24.301.301 |
| Effective date | 2026-09-26 |
| Adopted by | Montana Department of Labor and Industry, Building Codes Bureau (Building Standards Division), under Title 50, ch. 60, MCA |
| Adoption source | https://bsd.dli.mt.gov/building-codes-permits/current-codes |
| State amendments | State amendments at their own official document — https://rules.mt.gov/api/policy-library-public/collections/aec52c46-128e-4279-9068-8af5d5432d74/policies/1c5bd255-c8a7-4f8c-924e-426fbecc5244/document/de8759c1-f2d5-4df5-8d28-d0bafc79b238 |
Licensing
| Model | State individual licensing - two classes only: Journeyman Plumber and Master Plumber (MCA Title 37, ch. 69, pt. 3). A license is required to work in the field of plumbing (37-69-301 MCA); a journeyman may perform work only in the employment of a licensed master plumber unless board rule permits otherwise |
| Authority | Montana Board of Plumbers (Department of Labor and Industry) |
| Licensing source | https://boards.bsd.dli.mt.gov/plumbers/faq |
| License classes | https://boards.bsd.dli.mt.gov/plumbers/license-information/plumber-master |
Permits & inspections
Permits are handled through the Building Codes Bureau, and only Master plumbers are authorized to apply for and obtain plumbing permits (Board of Plumbers FAQ). ARM 24.301.301 replaces the UPC's permit-fee table with the state's own fee schedule for department enforcement.
How this record was verified
| Adoption | Verified |
| Amendments | Verified |
| Licensing | Verified |
| Permits & inspections | Verified |
Working notes
UPC 2024 replaced the UPC 2021 adoption effective September 26, 2026 (Dept. of Labor and Industry Current Codes page; the current ARM 24.301.301 text at rules.mt.gov adopts the 2024 edition). Some third-party compilations still show the 2021 edition - the ARM text and the DLI page control. Journeyman reciprocity only, with Oregon, Idaho, North Dakota and South Dakota; no master reciprocity.
Reference only. Compiled from the cited official sources as of the date shown; adoptions and rules change. Confirm with the authority having jurisdiction before designing or permitting work.