Treasure County, MT Building Permits & Septic Rules

In Treasure County, Montana, a single-family home generally does not need a state building permit unless it lies within a local jurisdiction that requires one; covered larger or commercial projects may need a state permit¹. Treasure County's countywide zoning is absent, but the Town of Hysham is a separate jurisdiction². A local health department drainfield permit is still required for septic work even when the property has state subdivision sanitation approval³.

At a glance

Building permit: A single-family home generally does not need a state permit unless a local jurisdiction requires one; covered larger or commercial work may need a state permit¹
Zoning: Countywide zoning is absent; Hysham and Crow Tribe lands may have separate authority²
Septic permits: County Sanitarian / Environmental Health, delegated by Montana DEQ⁴
Owner-builder: Exempt from Montana contractor licensing when working on your own property, subject to conditions⁵⁶
Well / water permit: Beneficial Water Use Permit generally required over 35 gpm or 10 acre-feet/year; smaller exempt wells need a Notice of Intent starting 2026⁷
Floodplain development: Permit required in a mapped Special Flood Hazard Area from the county Floodplain Administrator⁸
Land-division filing fees: $25 plus per-lot charges to file a plat or certificate of survey; a $400 engineer review fee applies to divisions under 76-3-207(4)⁹
State building code: Montana's code applies statewide; the state handles areas without a certified local program¹⁰

Who to call

Floodplain permits

Treasure County Floodplain Administrator (Courthouse)

Floodplain development permits for new development within a designated Special Flood Hazard Area in Treasure County; Montana DNRC lists a local floodplain administrator for the county at this courthouse address and phone number

(406) 342-5547

307 Rapelje Ave, Hysham, MT 59038

Septic permits

Treasure County Sanitarian / Environmental Health

Drainfield (septic) permits for Treasure County, delegated by Montana DEQ; the local health department issues this permit even when DEQ has already approved subdivision sanitation through a Certificate of Subdivision Approval (COSA)

Contact details are copied from each office’s official page and were checked against it on September 28, 2026.

Do you need a building permit in Treasure County, Montana?

A single-family residence in Treasure County generally does not need a Montana state building permit unless it is inside a local jurisdiction that requires one by ordinance or resolution¹. Montana requires a state building permit before covered construction, remodeling, moving, or a change of occupancy in areas under state jurisdiction, while exempting farm and ranch buildings, owner-use garages and storage buildings, and residential buildings with fewer than five dwelling units unless they serve transient guests¹. Areas without a certified local building-code program remain under the State Building Codes Bureau¹⁰. Separate electrical, plumbing, or mechanical permits may still apply, and a required building permit must issue before those permits or their work can begin¹. Montana contractor-licensing law allows an owner to work on the owner's own property, but that exemption does not erase applicable trade or building permits and is limited when the owner builds for prompt resale⁶.

Who handles floodplain and septic permits in Treasure County?

Treasure County's Floodplain Administrator works out of the courthouse in Hysham, at 307 Rapelje Ave, Hysham, MT 59038, phone (406) 342-5547¹¹. That office issues the floodplain development permit required for new construction, fill, or manufactured-home placement inside a mapped Special Flood Hazard Area¹¹⁸. Septic systems follow a separate track: the local health department issues the drainfield permit even when Montana DEQ has already issued a Certificate of Subdivision Approval¹²¹³. To reach the County Sanitarian / Environmental Health office, start with the Treasure County courthouse at (406) 342-5547¹¹.

Does Treasure County have zoning?

Treasure County's countywide zoning is absent: the county Growth Policy is non-regulatory and discusses zoning as a possible future action rather than a currently adopted county ordinance². Montana law allows a county with an adopted growth policy to adopt zoning regulations, but the growth policy itself is not zoning¹⁴². The Town of Hysham is a separate jurisdiction, and Crow Tribe lands may also fall under separate authority, so the countywide answer does not settle the rules in either place². Treasure County has not confirmed a numeric minimum dwelling size, minimum lot size, general building setback, lot-coverage limit, building-height limit, or private-land RV and tiny-home occupancy rule. Ask the county courthouse about the parcel and contact Hysham directly for land in or near town.

How do septic and well permits work in Treasure County?

Montana law requires a drainfield permit from the local health department for any new septic system, even on a property that already has a Certificate of Subdivision Approval from the state¹⁵. In Treasure County, the County Sanitarian / Environmental Health office is that local authority, issuing the drainfield permit regardless of any state-level sanitation approval already on file¹⁶¹³. Soils here make that more than paperwork: only 12.9% of the county's land is free of severe limitations for a conventional drain field, so budget for a site evaluation and likely an engineered or alternative system¹⁷. If your land needs more than a small domestic well, Montana generally requires a Beneficial Water Use Permit for groundwater use over 35 gallons per minute or 10 acre-feet a year; smaller 'exempt' wells at or under that threshold still need a Notice of Intent filed with the state water agency before use, with a $400 filing fee under the current process⁷. If you're dividing land and want to use Montana's agricultural exemption from full subdivision review, the divided parcel generally needs a covenant restricting its use exclusively to agriculture, on top of a certificate of survey and proof that taxes are paid¹⁸.

Can you live in an RV or tiny home on your land in Treasure County?

Treasure County has not confirmed whether long-term occupancy of an RV or a stand-alone tiny home is allowed on private unincorporated land. The absence of countywide zoning does not by itself answer sanitation, floodplain, subdivision, or occupancy questions². Montana's published RV limits for state trust land apply only to that public land, not to private acreage: RVs must remain within 50 feet of a customary access point, with stays limited to 2 days on leased trust land or 16 days within a 30-day period on unleased trust land or in a designated campground¹⁹. Ask the Treasure County courthouse about private-land occupancy before buying or moving an RV or tiny home onto a parcel, and contact Hysham separately for property within or near town.

What are the steps to build a home in Treasure County?

Ask whether the parcel is under state building-code jurisdiction or a separate local jurisdiction, then confirm whether the project is exempt; a single-family residence generally does not need a state building permit unless a local jurisdiction requires one¹.
For covered work, submit plans and the state Building Permit/Plan Review Application; the additional plan-review charge is 35 percent of the building-permit fee²⁰²¹.
Obtain the local health department's drainfield permit before septic installation, even if the parcel already has state subdivision sanitation approval¹³.
Address water rights before using groundwater; uses over 35 gallons per minute or 10 acre-feet per year require a permit, while a qualifying smaller well requires a Notice of Intent⁷.
Ask the Floodplain Administrator whether the site is in a designated Special Flood Hazard Area and obtain a development permit when required⁸.
For access onto a state highway, obtain an MDT approach permit or right-of-way agreement before construction²².

What should you check before buying land in Treasure County?

Water and soils are the headline concern here: annual precipitation runs just 15.1 inches a year, with severe drought hitting 12.5% of years, and only 12.9% of the county's soils are free of severe septic limitations, so a reliable well and a well-designed septic system both deserve real budget²³²⁴¹⁷. Land is a mix of terrain, with 55.6% at 15% slope or less and only 12.6% forested, so expect open range and cropland more than woods on most parcels²⁵²⁶. Zoning status is unconfirmed at the parcel level even though the county has no adopted ordinance, so before you buy, ask the county directly whether your specific parcel, or the nearby Town of Hysham, is subject to any zoning, subdivision or floodplain rule²⁷. If the tract you're buying was recently split from a larger parcel, confirm whether it needed a certificate of survey or subdivision plat, and whether it qualified for Montana's agricultural-use exemption from full subdivision review¹⁸. Property tax runs low here: about 0.6% effective, with a median bill near $1,326 a year, against a typical home value around $245,565²⁸²⁹³⁰.

Watch-outs

Treasure County has not confirmed minimum lot size, setbacks, or private-land RV, tiny-home, and manufactured-home occupancy rules; call the county courthouse at (406) 342-5547 before assuming either way¹¹.
The Town of Hysham is a separate jurisdiction inside Treasure County; confirm directly with Hysham if your land is in or near town².
Montana's state building-permit exemptions for farm buildings, personal garages and small residential buildings don't cover every project; a larger or commercial building, or one serving transient guests, may still need a state permit even though the county has none³¹.

Sources

Written September 28, 2026 from the rules quoted below, each taken from an official source and re-checked by an independent reviewer. This is research, not legal advice: rules change, so confirm with the office before you buy or build.

How Treasure County scores

Seclusion90100% ev.

Self-Sufficiency23100% ev.

Admin Boringness82100% ev.

Durability42100% ev.

Property Autonomy83100% ev.

Carry Cost8394% ev.

Evidence strength: 100%. This reports direct-source completeness and fallback use; it is separate from the score and is not a confidence interval. How it works →

$246kTypical home

0.6%Property tax

$996Land / acre

15.1"Annual rain

12.5% of yrsSevere drought

14.1 / yr (+11.2)Mid-century 100°F days

22.9 daysMid-century dry spell

1.01" (+4.4%)Mid-century 1-day rain

1.24×Wildfire change factor

100%Forward climate coverage

state median fallbackInsurance basis

651Radius comparison (15 mi)

0.8People / sq mi

0.1%Federal land

55.6%Land at 15% slope or less

12.9%Septic soil without severe limits

79,409 acWorkable land screen

12.6%Wooded land

12.2 tonsBiomass / forest ac

45.9°FAvg temp

Answers from the rulebook for Treasure County

What the ordinances and state agencies actually say — one answer per question, each quoted from the official source and independently re-checked.

Treasure County rules

County-wide zoningAbsent
Countywide zoning administered by Treasure County, including unincorporated Treasure County; the source separately identifies Hysham as an incorporated community with separate jurisdiction.
- The county growth policy is non-regulatory and is not zoning.
- The source states that county zoning would be adopted in the future, indicating no county zoning adoption in the policy.
- Hysham has a separate jurisdiction and is not covered by this county-administered absence claim.
“County zoning and future land use are complementary, and should the county adopt zoning in the future [...]”
Treasure County Growth Policy 2023 ↗Re-checked Sep 11, 2026
One more reviewed finding on this topic
- Absent — County zoning in Treasure County, excluding any separate zoning authority that may apply within the Town of Hysham or on Crow Tribe lands.
  “County zoning and future land use are complementary, and should the county adopt zoning in the future, both should be occasionally reviewed to ensure they are coordinated and compatible.”
  Treasure County Growth Policy 2023 ↗Re-checked Sep 26, 2026
Who permits septicCounty (with conditions)
Drainfield permitting for septic systems in Treasure County, including properties with a Certificate of Subdivision Approval
- The local health department administers the drainfield permit requirement even when DEQ has issued a COSA.
“Yes, even thought you have a COSA, a drainfield permit is still required by the local health department.”
Engineering Infrastructure & Subdivisions ↗Re-checked Sep 11, 2026
Septic permitRequired
Installation of a residential drainfield in Treasure County, including property that already has a Certificate of Subdivision Approval.
- A Certificate of Subdivision Approval does not eliminate the local health department drainfield permit requirement.
- The cited state page describes the requirement for local health departments generally and does not provide a Treasure County-specific fee, application process, inspection schedule, or exemptions.
“Yes, even thought you have a COSA, a drainfield permit is still required by the local health department.”
Engineering Infrastructure & Subdivisions ↗Re-checked Sep 26, 2026
One more reviewed finding on this topic
- Required — Installing a septic drainfield in Treasure County, including on a lot that already has a COSA
  “Yes, even thought you have a COSA, a drainfield permit is still required by the local health department.”
  Engineering Infrastructure & Subdivisions ↗Re-checked Sep 11, 2026
Building in a floodplainRequired
New development in designated Special Flood Hazard Areas within Treasure County, including development subject to the county floodplain program.
- A local floodplain administrator must determine whether an SFHA is designated for the stream of interest.
- Treasure County is listed by Montana DNRC as having a local floodplain administrator: Lindsey Kimball, 307 Rapelje Ave., Hysham, Montana, telephone 406-342-5547.
- The cited state guidance describes the permit requirement for new development within designated SFHAs; it does not establish a countywide permit requirement outside mapped or designated flood hazard areas.
“Anyone planning new development within a designated Special Flood Hazard Areas (SFHA). Check with local floodplain administrator to determine whether a Special Flood Hazard Areas (SFHA) has been designated for the stream of interest.”
Stream Permitting ↗Re-checked Sep 11, 2026
Permit feesPublished (with conditions)
Published Treasure County Clerk & Recorder fees for subdivision and townsite plats, certificates of survey, amendments, and examination of a division of land.
- The schedule is headed Effective Oct 1, 2025.
- Subdivision and townsite plat filings are charged $25.00 plus per-lot charges.
- Certificate of survey filings and amendments are charged $25.00 plus a per-tract or per-lot charge.
- Examination of a division of land includes a $400.00 engineer review fee under 76-3-207(4).
subdivision or townsite plat filing fee: 25 USD (plus $0.50 for each lot up to 100 and $0.25 for each lot over 100) · certificate of survey or amendment filing fee: 25 USD (plus $0.50 for each tract or lot) · division of land engineer review fee: 400 USD (76-3-207(4))
“FILING SUBDIVISION and TOWNSITE PLATS $25.00 Plus: for each lot up to 100 .50 for each lot over 100 .25 FILING CERTIFICATE OF SURVEY and AMENDMENTS Thereto $25.00 Plus: for each tract or lot .50 Examine a division of land –Engineer Review Fee 76-3-207(4) $400.00”
Recording and Filing Fees ↗Re-checked Sep 11, 2026

Montana rules that apply here

Building permitLimited
Building construction, remodeling, moving, or change of occupancy in Treasure County where Montana state building-code jurisdiction applies, including areas not covered by a certified local government program.
- A state building permit is required before construction for non-exempt buildings.
- State law exempts farm and ranch buildings; mining buildings on mining property; petroleum refineries and pulp and paper mills except office and shop buildings; residential buildings containing fewer than five dwelling units except when serving transient guests; and private garages and private storage buildings used for the owner's own use and not part of a commercial enterprise or business.
- A single-family residence does not require a state building permit unless located inside a local government's jurisdiction that requires one by ordinance or resolution.
- Projects within the jurisdictional limits of a certified local government program are excepted from the state permit process and may be subject to local requirements.
- Building permits must be issued before plumbing, mechanical, or electrical permits can be issued or related work begins.
residential dwelling units: < 5 dwelling units (Buildings containing fewer than five dwelling units are exempt from the state building permit requirement unless serving transient guests.)
“In the State's jurisdiction, state law exempts the following from the need to obtain state building permits: 1. farm and ranch buildings 2. mining buildings on mining property 3. petroleum refineries and pulp and paper mills (except office and shop buildings) 4. residential buildings containing less than five dwelling units (except when serving transient guests) 5. private garages and private storage buildings used for the owner's own use (not part of a commercial enterprise or business)”
Building Permits ↗Re-checked Sep 26, 2026
2 more reviewed findings on this topic
- Limited — Construction in Montana, including Treasure County, that is within the State Building Codes Program's jurisdiction and is not exempt.
  “In Montana a state building permit is required prior to the start of construction”
  Building Permits ↗Re-checked Sep 11, 2026
- Limited — Construction, remodeling, moving, alterations, additions, repairs, or changes of occupancy for buildings subject to Montana state building-code jurisdiction.
  “In Montana a state building permit is required prior to the start of construction for certain types of new buildings, and/or for alterations, additions, and repairs.”
  Building Permits ↗Re-checked Sep 11, 2026
Owner-builder exemptionConditional
Montana construction-contractor licensing, including owner work on property in Treasure County; this is not an exemption from applicable building, electrical, plumbing, mechanical, or other permits.
- The exemption covers an owner working on the owner's property, whether or not the owner occupies it.
- The exemption does not apply to an otherwise-covered owner constructing an improvement with the intention and purpose of promptly selling the improved property, unless the owner has continuously occupied the property as the owner's primary residence for at least 12 months.
primary-residence continuous occupancy: >= 12 months (Applies where the owner otherwise constructs an improvement for prompt sale of the improved property.)
“unless the owner has continuously occupied the property as the owner's primary residence for at least the last 12 months;”
MCA — Construction Contractors, Chapter 45 ↗Re-checked Sep 11, 2026
Building code adoptedAdopted (with conditions)
Montana's uniform state building code for residential and commercial buildings statewide.
- The currently listed codes are amended and adopted through Administrative Rules of Montana Title 24, Chapter 301.
- Cities, counties, and towns may enforce local building codes, all or in part, only through certified local building-code-enforcement programs.
- State-owned agencies must be permitted through the Montana Department of Labor and Industry.
- The listed 2021 International Building, Residential, and Existing Building Codes and related codes are effective June 11, 2022; the listed ASME boiler and pressure-vessel codes are effective November 6, 2021.
International Building Code edition: 2021 · International Residential Code edition: 2021 · effective date for listed principal codes: 2022-06-11 (ASME boiler and pressure-vessel codes listed on the official page are effective 2021-11-06)
“In addition, the program is responsible for adopting a uniform state building code, which is enforced statewide for residential and commercial buildings across Montana.”
Current Codes ↗Re-checked Sep 11, 2026
2 more reviewed findings on this topic
- Adopted — Residential and commercial buildings statewide in Montana, including areas of Treasure County under state jurisdiction.
  “In addition, the program is responsible for adopting a uniform state building code, which is enforced statewide for residential and commercial buildings across Montana.”
  Montana Building Codes Program ↗Re-checked Sep 26, 2026
- Adopted (with conditions) — Montana's uniform state building code, including projects in Treasure County that are not under a certified local building-code enforcement program.
  “In addition, the program is responsible for adopting a uniform state building code, which is enforced statewide for residential and commercial buildings across Montana.”
  Montana Building Codes Program ↗Re-checked Sep 26, 2026
InspectionsLimited
Buildings in Treasure County subject to Montana state building-code permitting and inspection.
- Inspections apply to projects requiring a state building permit.
- The permit holder must notify the inspector when work is ready for inspection and provide access.
- The permit holder is responsible for calling the building inspector at least 24 hours before a requested inspection.
- The inspector has 72 hours from notification to perform the requested inspection.
- Projects within certified local-government jurisdictions are inspected by the certified local jurisdiction rather than the state.
advance inspection notice: >= 24 hours · inspector response period: <= 72 hours (Measured from notification of a requested inspection.)
“It is the responsibility of the permit holder to call the building inspector at least 24 hours before a requested inspection, and that the inspector have 72 hours from the notification to perform the requested inspection.”
Is a State Building Permit Needed? ↗Re-checked Sep 26, 2026
2 more reviewed findings on this topic
- Limited — Projects in the State Building Codes Program's jurisdiction requiring inspection, including Treasure County projects assigned a State Building inspector.
  “TREASURE Jackson Payer 406-465-8874 Robert Spargo 406-475-0478 Nicholas Crowe 406-202-4347”
  Building Permits ↗Re-checked Sep 11, 2026
- Limited — Buildings and other projects requiring permits under Montana state building-code jurisdiction; certified local governments may perform inspections within their certified jurisdictional areas.
  “The BC Program establishes and enforces statewide codes by issuing permits and performing inspections.”
  Building Permits ↗Re-checked Sep 11, 2026
Certificate of occupancyLimited
Buildings constructed in accordance with the Montana state building code or a county, city, or town building code.
- The certificate must certify that the building conforms to the applicable building regulations.
- The statute addresses certificates for buildings constructed under the state or local building code; it does not establish a universal certificate requirement for every structure or every occupancy.
“A certificate of occupancy for a building constructed in accordance with the provisions of the state building code or county, city, or town building code must certify that the building conforms to the requirements of the building regulations applicable to it.”
50-60-107. Certificate of occupancy, MCA ↗Re-checked Sep 11, 2026
Living in an RVTemporary only (with conditions)
RV camping and temporary RV occupancy on Montana state trust land, including any such land within Treasure County.
- A Conservation License is required for dispersed camping unless camping is incidental to hunting or fishing under the conservation license.
- Group camping requires a special recreational use license.
- RV camping must be within 50 feet of a customary access point; motorized vehicles must be parked within 50 feet, and the camper or trailer may not be set up farther away.
- Stay is limited to 2 days on leased or licensed land.
- Stay is limited to 16 days within a 30-day period on unleased or unlicensed land.
- Stay is limited to 16 days within a 30-day period within a designated campground.
- Campfires are not allowed on leased land.
- The page states that most trust land east of the Continental Divide is leased and advises contacting the local DNRC field office to confirm whether land is leased.
RV distance from customary access point: <= 50 feet (Motorized vehicles must be parked within 50 feet; the camper or trailer may not be set up farther away.) · stay on leased or licensed land: 2 days · stay on unleased or unlicensed land: 16 days per 30-day period · stay within designated campground: 16 days per 30-day period
“TRAILER/RV etc. Camp within 50 ft of a customary access point. Motorized vehicles must be parked within 50 ft of a customary access point. You may not drive further to set up a camper or trailer.”
Camping ↗Re-checked Sep 11, 2026
Camping on your landLimited
Temporary camping on Montana state trust land, including any such land within Treasure County.
- A Conservation License is required for dispersed camping unless camping is incidental to hunting or fishing under the conservation license.
- Group camping requires a special recreational use license.
- Tent camping must be within 200 feet of a customary access point or navigable water body.
- Trailer/RV camping must be within 50 feet of a customary access point; motorized vehicles must be parked within 50 feet, and the camper or trailer may not be set up farther away.
- Stay is limited to 2 days on leased or licensed land.
- Stay is limited to 16 days within a 30-day period on unleased or unlicensed land.
- Stay is limited to 16 days within a 30-day period within a designated campground.
- Campfires are not allowed on leased land.
- The page states that most trust land east of the Continental Divide is leased and advises contacting the local DNRC field office to confirm whether land is leased.
tent distance from customary access point or navigable water body: <= 200 feet · trailer/RV distance from customary access point: <= 50 feet (Motorized vehicles must be parked within 50 feet; the camper or trailer may not be set up farther away.) · stay on leased or licensed land: 2 days · stay on unleased or unlicensed land: 16 days per 30-day period · stay within designated campground: 16 days per 30-day period
“TENT Camp within 200 ft of a customary access point or navigable water body. | TRAILER/RV etc. Camp within 50 ft of a customary access point.”
Camping ↗Re-checked Sep 11, 2026
Well permitLimited
New groundwater uses and wells in Treasure County under Montana water-rights law
- A water permit is required for groundwater uses over 35 gallons per minute or 10 acre-feet per year.
- Groundwater developments using 35 gallons per minute or less and no more than 10 acre-feet per year may qualify for an exception to the water-permit process.
- Beginning January 1, 2026, users intending to develop water through a permit exception must file a Notice of Intent with DNRC before using water from an exempt well.
- If a combined appropriation exceeds 10 acre-feet, a permitted water right is required regardless of flow rate.
groundwater flow threshold: <= 35 gallons per minute (Uses over this threshold require a water permit.) · annual groundwater volume threshold: <= 10 acre-feet per year (Uses over this threshold require a water permit; combined appropriations exceeding this threshold require a permitted water right.) · Notice of Intent filing fee: 400 USD (Applies to the Form 602I process described by DNRC.)
“Water Permits: A water permit is required for all surface water use and groundwater uses over 35 gallons per minute (gpm) or 10 acre-feet per year. [...] Permit Exceptions, a.k.a. Exempt Wells: Small groundwater developments that use 35 gpm or less and do not exceed 10 acre-feet per year are known as “exempt wells” and may qualify for an exception to the water permit process.”
Exempt Well Updates and Information ↗Re-checked Sep 11, 2026
Agricultural exemptionConditional
Certain land divisions in Treasure County under Montana's Subdivision and Platting Act, including transfers involving a covenant that limits use exclusively to agriculture.
- The exemption applies only to qualifying divisions under Title 76, chapter 3, part 2, MCA.
- The agricultural example requires a covenant running with the land that limits the use of the land exclusively to agriculture.
- Applicable zoning regulations still apply where the source states they apply.
- Exemptions may not be used to evade the Montana Subdivision and Platting Act.
- Local governments must adopt evasion criteria to evaluate whether a proposed exemption represents an intention to evade the Act.
- A certificate of survey and certification that property taxes and special assessments have been paid are required for the listed example divisions.
“provides that the divided land will be used exclusively for agricultural purposes”
Subdivisions ↗Re-checked Sep 11, 2026
Subdividing landRegulated (with conditions)
Subdivision activity in Treasure County subject to Montana's state sanitation-in-subdivisions review, including divisions creating parcels of less than 20 acres and condominiums, recreational camping vehicle parks, and mobile home parks regardless of parcel size.
- Montana DEQ review is limited to sanitation facilities, including water supply, sewage disposal, solid waste disposal, and storm drainage systems.
- Review occurs prior to creating the parcels.
- The review is intended to assure that adequate sanitation facilities can be constructed, operated, and maintained to support each parcel.
- This claim addresses the state sanitation-review component and does not establish the existence or scope of a separate Treasure County local subdivision-platting ordinance.
parcel size threshold: < 20 acres (Condominiums and recreational camping vehicle and mobile home parks are reviewed regardless of parcel size.)
“The DEQ Subdivision Program reviews divisions of land comprising less than 20 acres [...] This review is limited to sanitation facilities”
Engineering Infrastructure & Subdivisions ↗Re-checked Sep 26, 2026
Driveway accessLimited
New or modified driveway approaches and changes in property or approach use abutting MDT-maintained state highways in Treasure County.
- All new or modified approaches require either an approach permit or a right-of-way agreement.
- A change in use of property abutting a state highway or a change in use of an existing approach requires a new approach permit.
- The landowner must obtain the new permit; the owner must sign the application before review and approval.
- The MDT District Office determines whether an approach permit can be granted or whether the Systems Impact Process is necessary.
- For approaches on an existing or proposed access-control highway, approaches generating significant traffic volume, or approaches with significant environmental impacts, approval must follow the Systems Impact Process.
- A site plan and environmental checklist are required; construction cannot begin until required review, conditions, and permits are completed.
“ALL NEW OR MODIFIED APPROACHES REQUIRE EITHER AN APPROACH PERMIT OR A RIGHT-OF-WAY AGREEMENT. CHANGES IN THE USE OF PROPERTY ABUTTING A STATE HIGHWAY OR CHANGE IN USE OF AN EXISTING APPROACH REQUIRE A NEW APPROACH PERMIT.”
Approach Manual for Landowners and Developers ↗Re-checked Sep 11, 2026
One more reviewed finding on this topic
- Limited — New or modified driveway approaches intersecting Montana state highways, and changes in use of property abutting a state highway or an existing approach.
  “ALL NEW OR MODIFIED APPROACHES REQUIRE EITHER AN APPROACH PERMIT OR A RIGHT-OF-WAY AGREEMENT.”
  Approach Manual for Landowners and Developers ↗Re-checked Sep 11, 2026
Short-term rentalsLimited
Short-term rentals operated in Montana.
- A Property Manager license is required unless the operator qualifies for an exemption under MCA § 37-56-104 or MCA § 50-51.
- Local land-use, lodging, tax, and public-accommodation requirements may also apply.
application fee: 50 USD
“Short Term Rentals: A Property Manager license is required for short term rentals unless an operator qualifies for an exemption”
Property Management Program ↗Re-checked Sep 11, 2026
Permit processPartial
Projects in Treasure County that connect to Montana’s state highway system and may affect state highways, including commercial, residential, or industrial developments.
- SIAP applies to projects connecting to Montana’s state highway system.
- SIAP evaluates traffic, drainage, and environmental effects and defines mitigation requirements.
- The published process lists submission of a permit application and environmental checklist, technical review, design and approval, construction authorization, construction oversight and inspection, and permit issuance.
- MDT states that initial feedback typically takes 4–5 weeks; more complex projects may require multiple review iterations.
- SIAP applies when a project generates 150 or more trips per peak hour, requests new or modified highway access, involves land-use or zoning changes that increase highway impacts, or requires engineering solutions such as turn lanes, signals, or access modifications.
- If impacts are minimal and no off-site improvements are needed, the project may proceed under standard permit review instead.
initial MDT feedback timeframe: 4–5 weeks (varies by project complexity) · SIAP trip threshold: >= 150 trips per peak hour
“If your project connects to Montana’s state highway system, SIAP provides a structured review to ensure safety, efficiency, and sustainability. [...] Generates 150 or more trips per peak hour [...] If impacts are minimal and no off-site improvements are needed, the project may proceed under a standard permit review instead.”
System Impact Action Process (SIAP) ↗Re-checked Sep 11, 2026
One more reviewed finding on this topic
- Published (with conditions) — State-administered Montana building permits for covered non-exempt construction outside certified local-government jurisdictions.
  “To obtain a state building permit, submit construction plans and a Building Permit/Plan Review Application to the Building Codes Program for review and approval.”
  Building Permits ↗Re-checked Sep 11, 2026
Campground & park staysLimited
Camping in Montana Fish, Wildlife & Parks public-use sites.
- Camping is prohibited except in areas specifically designated or marked for camping.
- A camping unit, vehicle, equipment, or personal items may not be left overnight without a person present.
- Camping longer than 7 nights at one or more campsites in a public use area during any consecutive 30-day period is prohibited unless otherwise posted by the department.
- Designated occupancy limits must not be exceeded.
- Special-use-permit terms must be followed unless otherwise posted.
- Campsites must be vacated by 1 p.m. on the day of departure; camping facilities must be vacated by 12 p.m. on the day of departure.
maximum camping duration: <= 7 nights per consecutive 30-day period (unless otherwise posted by the department) · campsite departure time: 1 p.m. · camping-facility departure time: 12 p.m.
“Unless otherwise posted by the department, within a public use site it is prohibited to: [...] camp at one or more campsites in a public use area for a period of longer than 7 nights during any consecutive 30-day period, beginning with the first night occupied unless otherwise posted by the department;”
Public Use Rules and Regulations ↗Re-checked Sep 11, 2026
county zoning authorityGeneral
Montana boards of county commissioners adopting zoning regulations for all or parts of their jurisdictional areas, including unincorporated land.
- The board of county commissioners must have adopted a growth policy pursuant to Montana Code Annotated chapter 1.
- Zoning regulations must be adopted in accordance with Title 76, chapter 2.
- The statute also contains a temporary provision for counties that adopted a master plan before October 1, 1999; that provision authorized adoption or revision only until October 1, 2006.
“a board of county commissioners that has adopted a growth policy pursuant to chapter 1 is authorized to adopt zoning regulations”
76-2-201. County zoning authorized, MCA ↗Re-checked Sep 21, 2026

Still unanswered

We looked and could not find an official answer yet. Silence is not permission — ask the county directly.

Local zoning — Local zoning within Treasure County, including the separately governed Town of Hysham and unincorporated areas.
Zoning districts — Zoning districts published or administered by Treasure County.
Minimum dwelling size — Minimum dwelling size in unincorporated Treasure County.
Minimum lot size — Minimum lot size in unincorporated Treasure County.
Setbacks — Building setbacks in unincorporated Treasure County.

8 more unanswered

Lot coverage
Building height
Tiny homes
Manufactured homes
Accessory dwellings
Septic inspection
Off-grid sanitation
Mandatory utility hookup

Each answer was extracted from an official source and independently re-checked against that source by a second reviewer. That is an evidence check, not legal advice. Rules change; confirm with the authority before you buy or build.

Living off-grid in Treasure County, Montana

Is Treasure County a good place to live off-grid or homestead?

Treasure County scores 59/100 on the Bolthole Index, a solid county profile. Its strengths: deep seclusion — about 651 people within 15 miles and manageable long-term carry cost. Watch-outs: thin water margin (15.1″/yr rainfall) and elevated current hazard exposure.

Do you need a building permit in Treasure County, Montana?

Treasure County does not require a county building permit for a home in unincorporated areas, and it has no county-wide zoning. Onsite septic is permitted by Treasure County Sanitarian / Environmental Health (DEQ-delegated). Owner-builders may act as their own contractor to build their home. These answers are quoted from official sources and independently re-checked. Rules change and cities within the county differ — always confirm with the county before you buy or build.

Can you live in an RV or tiny home on your land in Treasure County?

Living in an RV on your own land in Treasure County is allowed on a temporary basis only: Statewide rule. RV camping and temporary RV occupancy on Montana state trust land, including any such land within Treasure County. A Conservation License is required for dispersed camping unless camping is incidental to hunting or fishing under the conservation license. Group camping requires a special recreational use license. Confirm with the county before relying on it.

How much does land cost in Treasure County, Montana?

Land in Treasure County runs about $996 per acre, based on the latest county data.

What is the water situation in Treasure County?

Treasure County gets about 15.1" of rain a year, with severe drought in roughly 12.5% of years.

How remote is Treasure County?

A typical private-land location has about 651 people within 15 miles and 210,851 within 100 miles. These radius catchments are the published fallback where road routing is unavailable.

Building permits, zoning and land rules in Treasure County, Montana

At a glance

Who to call

Do you need a building permit in Treasure County, Montana?

Who handles floodplain and septic permits in Treasure County?

Does Treasure County have zoning?

How do septic and well permits work in Treasure County?

Can you live in an RV or tiny home on your land in Treasure County?

What are the steps to build a home in Treasure County?

What should you check before buying land in Treasure County?

Watch-outs

Sources

Treasure County in Montana

How Treasure County scores

Find land. Bring the promising ones back.

Parcel due diligence

Answers from the rulebook for Treasure County

Treasure County rules

Montana rules that apply here

Still unanswered

Living off-grid in Treasure County, Montana

Is Treasure County a good place to live off-grid or homestead?

Do you need a building permit in Treasure County, Montana?

Can you live in an RV or tiny home on your land in Treasure County?

How much does land cost in Treasure County, Montana?

What is the water situation in Treasure County?

How remote is Treasure County?

How Treasure compares in Montana