Montana building permits

Where to get a building permit in Montana

Apply to the building department of the city, town or county where the property is (the steps).

State rules on which work needs a permit

Mont. Code Ann. §§ 50-60-102, -108, -503, -506, -602

• State building code does not apply to the listed buildings. Except as provided in subsection (5), the state building code, as defined in 50-60-203(3), does not apply to…³
• Excludes residential buildings under five dwelling units, farm and ranch buildings and private owner-use garages or storage structures unless locally adopted. …residential buildings containing less than five dwelling units or their attached-to structures, any farm or ranch building of any size, and any private garage or private storage structure of any size used only for the owner's own use, located within a county, city, or town, unless the local legislative body by ordinance or resolution makes the state building code applicable to these structures…³
• State may not enforce for the excluded buildings. Except as provided in subsection (5), the state may not enforce the state building code under 50-60-205 for the buildings and equipment referred to in subsection (1).³
• Permit required for covered buildings. Any person who desires to construct a building which is subject to the provisions of parts 1 through 4 must apply for a permit from the appropriate authorities.⁴
• No state plumbing permit for minor replacement or repair work that does not have a significant potential for creating a condition hazardous to public health and safety. A permit is not required for any minor replacement or repair work, the performance of which does not have a significant potential for creating a condition hazardous to public health and safety.⁵
• Owner of residential property who personally installs sanitary plumbing and potable water supply piping needs no state plumbing permit. This part does not prohibit the owner of residential property from making an installation for all sanitary plumbing and potable water supply piping without a permit if the owner personally does the work.⁵
• State plumbing law (part 5) does not apply to plumbing on farms having their own individual water supply or sewage disposal system. This part shall not be construed to apply to or to affect plumbing installations in any mines, mills, smelters, refineries, public utilities, railroads, or plumbing installations on farms having their own individual water supply or sewage disposal system.⁶
• State electrical law (part 6) does not apply to installation, alteration or repair of low-voltage electrical signal and communications equipment and optical fiber cable. …the installation, alteration, or repair of low-voltage electrical signal and communications equipment and optical fiber cable.⁷
• Plugging in an appliance is not installation. A person who plugs in an electrical appliance where an approved electrical outlet is already installed may not be considered as an installer.⁷

Homeowners doing their own work

Mont. Code Ann. §§ 37-45-104(13), 37-68-103(3), 37-69-102(1)(a), 50-60-506(4)

• Owner may do own electrical work without a license. Except as provided in subsection (3)(b), this chapter does not require an individual to hold a license to perform electrical work on the individual's own property or residence if the property or residence is maintained for the individual's own use.⁸
• Exception for grid-tied generators. Subsection (3)(a) does not include an exemption for an individual who is performing electrical work on a grid-tied generator located at the individual's own property or residence.⁸
• Owner of a personal-use single-family residence may do plumbing without a license. …when an owner of a single-family residence used exclusively for the owner's personal use installs all sanitary plumbing and potable water supply piping…⁹
• No state plumbing permit if the owner personally does the work. This part does not prohibit the owner of residential property from making an installation for all sanitary plumbing and potable water supply piping without a permit if the owner personally does the work.⁵
• Owner working on own property exempt from contractor law, with resale limit. …to an owner working on the owner's property, whether occupied by the owner or not, but this exemption does not apply to an owner who is otherwise covered by this chapter who constructs an improvement on the owner's property with the intention and for the purpose of promptly selling the improved property, unless the owner has continuously occupied the property as the owner's primary residence for at least the last 12 months…¹⁰
• Owner or licensed electrical contractor delivers the permit to the power supplier. …power suppliers may not connect with or energize an electrical installation under this part unless the owner or a licensed electrical contractor has delivered to the power supplier an electrical permit covering the installation…¹¹

Contractor licensing

Mont. Code Ann. §§ 37-45-201, 37-68-301, 37-69-301 · in effect January 1, 2026¹⁸

• State construction contractor license required. An individual or business entity may not engage in business as a construction contractor without a current license from the department.¹²
• Definition of construction contractor. …in the pursuit of an independent business, offers to undertake, undertakes, or submits a bid to construct, alter, repair, add to, subtract from, improve, move, wreck, or demolish for another a building, highway, road, railroad, excavation, or other structure, project, development, or improvement attached to real estate, including the installation of carpeting or other floor covering, the erection of scaffolding or other structures or works, or the installation or repair of roofing or siding…¹³
• Application fee set by the department, amount not in statute. Each applicant for a construction contractor license shall pay an application fee established by the department.¹⁴
• Penalty up to $5,000 for unprofessional conduct. …a penalty of up to $5,000, as determined by the department…¹⁵
• Electricians must be licensed. A person may not engage in or work at the business or trade of or hold out to the public that the person is an electrician, electrical contractor, residential electrician, journeyman electrician, or master electrician in this state until the person has received from the department a license or permit to work as an electrical contractor, residential electrician, journeyman electrician, or master electrician.¹⁶
• Plumbers must be licensed. Except as provided in 37-69-102, a person working at the field of plumbing in this state, either as a master plumber or as a journeyman plumber, shall first obtain a license as provided in Title 37, chapter 69, part 3.¹⁷

Can local rules be stricter?

Local governments may not require registrations, licenses or bonds for the same purpose¹⁹

Handyman limits

Mont. Code Ann. § 37-45-104(8), (24)

• $2,500. …to work or operation on one undertaking or project considered of a casual, minor, or inconsequential nature, by one or more contracts, the aggregate contract price of which, for labor and materials and all other items, is less than $2,500 a job.¹⁰
• No splitting to evade the limit. The exemption prescribed in this subsection does not apply when the work or construction is only a part of a larger or major operation, whether undertaken by the same or a different construction contractor, or in which a division of the operation is made into contracts of amounts of less than $2,500 a job for the purpose of evasion of this chapter or otherwise.¹⁰
• Independent contractors with no employees exempt. …to an independent contractor who has no employees. However, an independent contractor may voluntarily elect to register under this chapter.¹⁰

Deadlines for permit decisions and inspections

Mont. Code Ann. §§ 50-60-106(2)(c), 50-60-118(5)(d), 50-60-119

• 7 business days. The department or local building department shall provide the text or citations requested under subsection (1) within 7 business days.²⁰
• $50. …it shall pay to the requesting party a sum of $50 for each day beyond the required response period until the text or citation is provided to the requesting party.²⁰
• Zoning or subdivision review may come first. If a project also requires zoning, subdivision, or other approval, the department or local building department may require those reviews to be completed before determining a building application is complete.²⁰

Private plan review and inspections

No private-inspector statute found; Mont. Code Ann. §§ 50-60-106(4), 50-60-304(3) are related

• Local government may contract out enforcement. A county, city, or town may contract for the enforcement of its building code.²¹
• Certified programs may inspect outside their limits on written request. The inspections are requested in writing by the owners or builders of the buildings to be inspected.¹

Limits on permit fees

Mont. Code Ann. §§ 50-60-106(2)(g), 50-60-301(4), 50-60-118(3)

• Local fees must be necessary, reasonable and uniform. …ensure that all construction-related fees or charges imposed and collected by the county, city, or town are necessary, reasonable, and uniform and are…¹
• 0.5%. …allocated and remitted to the department, in an amount not to exceed 0.5% of the building fees or charges collected, for the building codes education program established in 50-60-116.¹
• Fees reduced above 36 months of need. …reduced if the amount of the fees or charges accumulates above the amount needed to enforce building codes for 36 months.¹
• Plan fees reduced for approved model plans. Local building departments shall reduce plan examination fees commensurate with the reduced time and effort expended resulting from the department's examination provided for in subsection (1).²²

Selling a home with unpermitted work

Mont. Code Ann. §§ 70-20-501 to -504

• Written disclosure of known adverse material facts required. In any transfer of residential real property in the state, the seller shall provide a disclosure statement to a buyer disclosing any adverse material facts that concern the residential real property and of which the seller has actual knowledge.²³
• Unpermitted substantial additions or alterations must be disclosed if known. …whether any substantial additions or alterations have been made to the residential real property without a building permit…²³
• Timing: before or with contract execution. The disclosure statement must be provided by the seller prior to or contemporaneously with the execution of a contract, either directly or via the real estate agent or other authorized representative of the seller, and must be provided to the buyer or the real estate agent or other authorized representative of the buyer.²³
• Buyer may waive in the contract. …transfers when in the contract the buyer has waived the right to receive a disclosure statement at the time of submitting the offer to purchase to the seller.²⁴
• 3-day rescission if delivered after contract. …if a disclosure statement is provided by a seller to a buyer after the execution of a contract, the buyer shall have 3 days from the day the seller or the real estate agent or other authorized representative of the seller delivers the disclosure statement to rescind the contract…²⁵

Applies to

One to four dwelling units or an individually owned unit²⁶

What local governments may change

Mont. Code Ann. §§ 50-60-301(2), 37-45-204

• Statewide; local amendments not allowed. Except as provided in subsection (2)(b), a county, city, or town may not adopt or enforce a building code that is more stringent than the building code adopted by the department or as required by state law.²⁷
• Voluntary energy incentives may exceed the state code. New construction is not required to meet local standards that exceed state energy conservation standards unless the building contractor elects to receive a local incentive.²⁷
• Local governments may not license contractors for the same purpose. A political subdivision of the state may not require or issue any registrations, licenses, or bonds for the same or a similar purpose.¹⁹

Accessory dwelling units (ADUs)

Mont. Code Ann. §§ 76-2-345 (municipal), 76-2-215 (county)

• At least one ADU by right in municipal zoning. A municipality shall adopt regulations under this chapter that allow a minimum of one accessory dwelling unit by right on a lot or parcel that contains a single-family dwelling.²⁸
• Attached, detached or internal. An accessory dwelling unit may be attached, detached, or internal to the single-family dwelling on a lot or parcel.²⁸
• 1,000 square feet. If the accessory dwelling unit is detached from or attached to the single-family dwelling, it may not be more than 75% of the gross floor area of the single-family dwelling or 1,000 square feet, whichever is less.²⁸
• No required added parking. …require that a lot or parcel have additional parking to accommodate an accessory dwelling unit or require fees in lieu of additional parking…²⁸
• No owner-occupancy requirement. …require that the single-family dwelling or the accessory dwelling unit be occupied by the owner…²⁸
• No impact fees. …assess impact fees on the construction of an accessory dwelling unit…²⁸
• $250. The one-time application fee may be up to $250 for each accessory dwelling unit.²⁸
• Usual building fees still allowed. Nothing in this section prohibits a municipality from requiring its usual building fees in addition to the application fee.²⁸
• Noncompliant regulations void. Regulations in effect on or after January 1, 2024, that apply to accessory dwelling units and do not comply with this section are void.²⁸
• Building and fire codes still apply. The provisions of this section do not supersede applicable building codes, fire codes, or public health and safety regulations adopted pursuant to Title 50, chapter 2.²⁸
• At least one ADU by right in zoned county areas. In jurisdictional areas where the board of county commissioners has established zoning regulations under this part, the regulations must allow a minimum of one accessory dwelling unit by right on a lot or parcel that contains a single-family dwelling.²⁹
• Expedited sanitation provisions terminate September 30, 2029. Section 4. Termination. [Sections 1(7) and 2] terminate September 30, 2029.³⁰

Can local rules be stricter?

Local rules may be more permissive only²⁸