Bolthole Index

Madison County, Montana

Zoning, building permits and sewer rules in the Town of Ennis, Montana

The Town of Ennis, Montana adopts and enforces its own zoning, including in an extraterritorial area shown on its zoning map1. Every property inside town limits must connect to the town's central sewer system2. We could not confirm how building permits for a new house work inside Ennis, so call Town Hall before you buy. Madison County's septic permits are a separate process3.

At a glance

Zoning
Yes: the Town of Ennis zones town limits and an extraterritorial area1
Zoning districts
Agricultural, residential, mixed, nonresidential and overlay districts4
Lot size, low-density residential (R-LD)
7,500 sq ft lot, 0.5 acre per dwelling unit5
Sewer
Connection to the town's central sewer is required inside town limits2
Building permit
Not confirmed for Ennis; state permits cover certain buildings, with exemptions6
Septic (county)
Madison County requires a permit for new or replaced wastewater systems3

Who to call

Planning & zoning

Town of Ennis

Town zoning permits (site zone, conditional use, temporary use, sign and fence permits) and encroachment permits inside Ennis

(406) 682-4287

328 W Main Street, Ennis, MT 59729

Septic permits

Madison County Sanitarian

Madison County wastewater-system (septic) permits and construction/demolition permits

(406) 898-4338

7 Placer Loop, Virginia City, MT 59755

Contact details are copied from each office’s official page and were checked against it on October 23, 2026.

Off-grid gear

Going off-grid in Town of Ennis means bringing your own water and power. The kit we’d start with:

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Does Ennis, Montana have zoning, and what does it mean for lot size and setbacks?

Yes. The Town of Ennis zones the land inside its corporate limits and the extraterritorial area shown on its official zoning map1. The zoning code divides that area into agricultural districts (AG-640, AG-160, AG-80), residential districts (R-RD, R-LD, R-MD, R-TD), mixed and nonresidential districts, and overlays4. Rules depend on the district, so find your parcel's district on the zoning map first.

In the R-LD low-density district, a lot needs at least 7,500 square feet and 0.5 acre per dwelling unit5. Required yards there are 20 feet in front, 10 feet on the sides and 20 feet in the rear7, and buildings top out at 25 feet8. In R-MD, lots start at 5,000 square feet and 0.25 acre per dwelling unit9. The rural R-RD district needs a 3-acre lot and 10 acres per dwelling unit10, and AG-160 needs 160 acres11. Hardship variances and overlay districts can modify these figures5.

Do you need a building permit in Ennis, and who issues it?

We could not confirm whether Ennis issues its own building permits for a new house or relies on the state. The Town of Ennis website lists site zone, conditional use, temporary use, sign, fence and encroachment permits12, and that menu does not settle the building permit question12.

At the state level, Montana requires a state building permit for certain new buildings, alterations, additions and repairs, but the state permit does not apply inside a certified local government program6. State exemptions include residential buildings with fewer than five dwelling units, unless they serve transient guests6. Call the Town of Ennis at (406) 682-428713 to ask whether a certified local program covers your address.

How do septic permits work in Ennis?

Inside town limits, septic is probably not your route: the town's zoning code says all properties within town limits must connect to the town's central sewer system2. We could not confirm whether a new home at the edge of town must connect when the sewer main is not adjacent, so ask the town before you plan a septic system.

For land outside town sewer, Madison County requires a permit for any new, repaired, replaced or altered wastewater treatment system3. The Madison County Sanitarian14 handles those permits, and the county's application requires a Madison County licensed installer3. Water-well rules inside Ennis were not confirmed.

Can you live in an RV or tiny home in Ennis?

We could not confirm Ennis's rules on RV occupancy, tiny homes, accessory dwellings or manufactured homes. The town website lists a temporary use permit12, but its terms were not confirmed, so do not assume a camper is allowed on a vacant lot. Ask the Town of Ennis13 in writing before you buy or move a unit onto a lot.

Building a home in Ennis: the steps, in order

  1. Find the parcel's zoning district on the official zoning map, then check lot size, yards and height for that district4.
  2. Call the Town of Ennis13 to confirm which permits apply, including any site zone permit12.
  3. Confirm whether a state or certified local building permit is needed for your project6.
  4. Plan to connect to the town's central sewer system2.
  5. If the lot is outside town sewer, apply to the Madison County Sanitarian14 for a wastewater permit3.

What stays with Madison County (and what to check before you buy)

Land outside the Ennis zoning area is governed by Madison County, not the town. The county has no comprehensive countywide zoning and relies on subdivision regulations15. Land splits are reviewed under Madison County's subdivision regulations, and parcels created under the agricultural exemption cannot take a house unless the covenant is revoked through subdivision review16. For land outside town, see the Madison County page.

Madison County's effective property tax rate is 0.4%17. Only about 16.3% of county soils rate as not limited for a conventional drain field, so expect a site evaluation outside town sewer18.

Watch-outs

  • Ennis's building permit, inspection and certificate-of-occupancy rules inside town were not confirmed, so ask the Town of Ennis before you sign a purchase contract13.
  • Zoning also reaches an extraterritorial area outside town limits, so a parcel with an Ennis address or just beyond the town line may still fall under town zoning1.
  • Montana's state building codes move to the 2024 International Building Code and International Residential Code editions effective September 26, 202619.

Sources

  1. Ennis Title 11 Zoning Regulations, Chapter 1 Legal and Administrative Provisions (Town of Ennis), quoted and re-checked
  2. Ennis Title 11 Zoning Regulations, Chapter 3 Zoning Districts and Overlay Districts (Town of Ennis), quoted and re-checked
  3. Septic System Information, quoted and re-checked
  4. Ennis Title 11 Zoning Regulations, Chapter 3 Zoning Districts and Overlay Districts (Town of Ennis), quoted and re-checked
  5. Ennis Title 11 Zoning Regulations, Chapter 3 Zoning Districts and Overlay Districts (Town of Ennis), quoted and re-checked
  6. Building Permits (Montana statewide rule), quoted and re-checked
  7. Ennis Title 11 Zoning Regulations, Chapter 3 Zoning Districts and Overlay Districts (Town of Ennis), quoted and re-checked
  8. Ennis Title 11 Zoning Regulations, Chapter 3 Zoning Districts and Overlay Districts (Town of Ennis), quoted and re-checked
  9. Ennis Title 11 Zoning Regulations, Chapter 3 Zoning Districts and Overlay Districts (Town of Ennis), quoted and re-checked
  10. Ennis Title 11 Zoning Regulations, Chapter 3 Zoning Districts and Overlay Districts (Town of Ennis), quoted and re-checked
  11. Ennis Title 11 Zoning Regulations, Chapter 3 Zoning Districts and Overlay Districts (Town of Ennis), quoted and re-checked
  12. Town of Ennis home page (permitting menu) (Town of Ennis), quoted and re-checked
  13. Town of Ennis (ennismontana.org)
  14. Madison County Sanitarian (madisoncountymt.gov)
  15. Madison County - Planning Office Publications/Regulations (2026 county census)
  16. Planning Regulations and Plans, quoted and re-checked
  17. Effective property tax rate: Bolthole Index county data
  18. Share of soils USDA rates "not limited" for a conventional septic drain field (SSURGO). A strict rating: the median county is about 6% and a tenth of counties are 0%, so a low figure means most lots need a site evaluation or an engineered system, not that septic is impossible. Cite it only with that caveat: Bolthole Index county data
  19. Current Codes, quoted and re-checked

Written October 23, 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.

Answers from the rulebook for Town of Ennis

Town of Ennis’s own rules

  • Local zoningPresent

    Land inside Ennis town's corporate limits and the extraterritorial zoning jurisdiction shown on the official zoning map (Title 11, section 11-1-4)

    • Zoning ordinance is adopted under the municipal zoning enabling act, MCA 76-2-301 through 76-2-328 (section 11-1-2).
    • The posted code is current through Ord. 159-2024, passed 10-30-2024 per the American Legal Publishing overview; the publisher's disclaimer says the official printed code should be consulted.
    • Extraterritorial zoning boundaries are on the official zoning map, which this research did not open.
    “the zoning jurisdiction of the town shall include the land within the town's corporate limits and within the extraterritorial zoning jurisdiction boundaries”
  • Zoning districtsPublished

    Land inside Ennis town's zoning jurisdiction

    • Districts listed in 11-3-2: agricultural ag-640, ag-160, ag-80; residential r-rd, r-ld, r-md, r-td; mixed l-cr, c-cr; nonresidential hc, c-i, p-i; overlays tnd, fpm, cs.
    • The district map (official zoning map) was not opened; only the text list was read.
    “the ennis planning and zoning jurisdictional area is divided into the following zoning districts:”
  • Minimum lot sizeSpecified

    R-LD residential - low density district inside Ennis town (main low-density single-family district)

    • Requirements are observed in all circumstances unless modified under an overlay district or a hardship variance (11-3-4a).
    • Parcels nonconforming by size that were subdivided before the title may be used if the proposed uses are treated as conditional uses (11-3-4b).

    lot area: >= 7500 sq ft · minimum area per dwelling unit: >= 0.5 acre

    “r-ld 1 / 2 acre 7,500 sq. ft. 20 ft. 10 ft. 20 ft. 75 ft. 25 ft. none”
    3 more reviewed findings on this topic
  • SetbacksSpecified

    AG-160 agricultural - 160 district inside Ennis town zoning jurisdiction

    • Footnote 1 applies to the marked side and rear values: the distance shall be equal to the height of buildings within 200 feet but no less than 10 feet.
    • Footnote 2 applies to the height and intensity columns, not to setbacks.

    front yard: >= 50 ft · side yard: >= 10 ft (footnote 1: equal to height of buildings within 200 feet but no less than 10 feet) · rear yard: >= 10 ft (footnote 1: equal to height of buildings within 200 feet but no less than 10 feet) · street frontage: >= 1200 ft

    “ag-160 160 acres 160 acres 50 ft. 1) 10 ft. 1)10 ft. 1,200 ft. 2) none 2) none”
    3 more reviewed findings on this topic
  • Building heightSpecified

    R-LD residential - low density district inside Ennis town

    • Maximum from the 11-3-4 matrix; the height column applies in all circumstances unless modified by overlay or hardship variance.

    maximum building height: <= 25 ft

    “r-ld 1 / 2 acre 7,500 sq. ft. 20 ft. 10 ft. 20 ft. 75 ft. 25 ft. none”
    3 more reviewed findings on this topic
  • Mandatory utility hookupSewer (with conditions)

    Properties inside Ennis town limits: connection to the town's central sewer system

    • Stated as a note to section 11-3-1 of the zoning chapter; the Title 10 sewer and water chapter was not opened.
    • Water connection requirement not found in this research: utility_connection water remains unknown.
    • Whether a new home must connect when the sewer is available at a distance is not stated in the text read.
    “1. all properties within the town limits must connect with the town's central sewer system.”
  • Permit processPartial

    Town of Ennis zoning-related permits listed on the town website (site zone, conditional use, temporary use, sign, fence permits)

    • The home page navigation lists the permit types only; review steps, fees, forms and timelines were not opened.
    • Permit types listed on the menu do not establish whether a building permit is required for a house.
    “permitting conditional use permit encroachment permit fence permit sign permit site zone permit temporary use permit special event”

Still unanswered

We looked and could not find an official answer yet. Silence is not permission; ask Town of Ennis or Madison County directly.

  • Building permit — New dwelling construction inside Ennis town
  • Owner-builder exemption — Owner-builder construction inside Ennis town
  • Building code adopted — Building construction inside Ennis town
  • Inspections — Building inspections inside Ennis town
  • Certificate of occupancy — Certificate of occupancy for new homes inside Ennis town
18 more unanswered
  • Minimum dwelling size
  • Lot coverage
  • Living in an RV
  • Camping on your land
  • Tiny homes
  • Manufactured homes
  • Accessory dwellings
  • Who permits septic
  • Septic permit
  • Septic inspection
  • Off-grid sanitation
  • Well permit
  • Agricultural exemption
  • Subdividing land
  • Driveway access
  • Building in a floodplain
  • Short-term rentals
  • Permit fees

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.

Unanswered questions are usually a sign that Town of Ennis publishes no rule on the point, not that none exists. Madison County’s page lists the county offices to call.

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