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Off-Grid Laws › Wyoming

Off-Grid Living in Big Horn County, Wyoming

Big Horn County, Wyoming has no countywide zoning or building code in unincorporated areas, making it one of the more permissive places for off-grid living, but septic systems and wells still require permits from the county Land Planning Department and the Wyoming State Engineer's Office respectively.

Is it legal to live off-grid in Big Horn County, Wyoming?

There is no outright ban on living off-grid in Big Horn County, Wyoming - it is generally possible. Zoning and land use are generally allowed, putting a cabin, tiny home, or RV on raw land is generally allowed, and building permits are set locally and vary by area. Plan around septic/wastewater (restricted) and disconnecting from utilities (generally allowed). Because these rules are set locally, confirm the specifics with Big Horn County before you buy land or build.

Read this before you act on anything below. This is my researched starting point for Big Horn County, not legal advice and not a guarantee. Rules change, and the deciding facts on any specific parcel (setbacks, perc results, overlay districts, deed restrictions, road frontage) live at the county or town office, not in any database. Before you buy land or build, confirm the current rules directly with the local zoning and health offices - the sources on this page tell you exactly who to call.
Primary-source verified · reviewed Aug 202620 government, statute, or municipal sources are linked below; the verdict card cites them where a match exists.

The verdict for Big Horn County

  • Zoning: Generally allowed
  • Dwellings, tiny homes: Generally allowed
  • Building permits: Varies locally
  • Septic: Restricted
  • Greywater reuse: Unclear - verify
  • Rainwater harvesting: Unclear - verify
  • Private wells: Restricted
  • Living disconnected from utilities: Generally allowed

Big Horn County at a glance

Zoning & raw-land occupancy
Generally allowedBig Horn County has no countywide zoning ordinance; the county Planning & Zoning Commission mainly handles subdivisions, floodplains, and airport zones. Municipalities within the county may have their own zoning that overrides this. source
Dwellings, tiny homes & RVs
Generally allowedNo county-specific rule restricts tiny homes, mobile homes, or RVs in unincorporated Big Horn County; the county has no building codes there. Municipal boundaries may have their own separate requirements. source
Building permits & codes
Varies locallyRural Big Horn County has no adopted building code, but a Development Permit Application is still required through the county Land Planning Department to check for floodplain or airport zone issues; electrical/fire codes fall under the Wyoming State Fire Marshal by default. source
Septic & composting toilets
RestrictedA county-issued septic permit (via a septic application workbook) is required from Big Horn County Land Planning, built to Wyoming DEQ Water Quality Division standards. Composting toilets are not separately addressed at the county level; confirm with the office. source
Greywater reuse
Unclear - verifyNo Big Horn County page addresses greywater specifically; this appears to inherit Wyoming's state DEQ permit-by-rule framework, but it's not confirmed at the county level. Ask the Land Planning Department directly.
Rainwater harvesting
Unclear - verifyNo Big Horn County ordinance on rainwater harvesting was found; it appears to inherit the state's permissive baseline, but this is not confirmed at the county level.
Private wells & water rights
RestrictedAny domestic or stock well requires a permit from the Wyoming State Engineer's Office, Ground Water Division; the county Land Planning Department provides the application forms but does not issue the permit itself. source
Living disconnected from utilities
Generally allowedNo Big Horn County rule requires connecting to grid electric, gas, or municipal water/sewer; off-grid power setups appear to inherit Wyoming's permissive state stance. Utility providers may require an approved address only if you choose to seek their service. source

Who to call in Big Horn County

Offices named on official pages during research. Phone numbers appear only when the official page showed one; confirm hours and jurisdiction before you drive out.

I've been digging through Big Horn County, Wyoming's rules for anyone thinking about going off-grid out there, and the short version is: this is about as light-touch as county regulation gets in the Lower 48, with a few notable exceptions you shouldn't skip.

Zoning. Big Horn County has no countywide zoning ordinance. Under Wyoming statute (W.S. 18-5-202) the county did establish a Planning & Zoning Commission, but per the county's own Land Planning Department, its job is mostly subdivision review, floodplain review, and a couple of localized airport protection zones, not general land-use control. So on raw rural land, you're generally not fighting a zoning map. That said, if you're inside a town's municipal boundary, you're playing by that town's rules, not the county's, so check with the municipality directly.

Dwellings, tiny homes, RVs. I found no county rule specifically targeting tiny homes, mobile homes, or RVs in unincorporated Big Horn County. The county says plainly it has no building codes for unincorporated parcels. This inherits Wyoming's generally permissive state baseline.

Building permits. Even without a building code, the county still requires a Development Permit Application through the Land Planning Department before you start a project, mainly so staff can check whether you're in a 100-year floodplain or an airport zone. Contractors still have to follow applicable electrical and fire codes, which statewide fall under the State Fire Marshal / Council on Fire Prevention and Electrical Safety, since the county hasn't taken over that enforcement itself.

Septic. This is one area where the county is genuinely restrictive: any septic system requires a permit from Big Horn County Land Planning, using a septic workbook application, built to Wyoming DEQ Water Quality Division standards. Composting toilets aren't separately addressed by the county as far as I can find, so I'd assume state DEQ oversight applies and confirm directly.

Greywater and rainwater. No county-specific rules on either turned up in my research. Both appear to just inherit Wyoming's state-level (fairly permissive) baseline, but I'd call the Land Planning office to be sure nothing local has changed.

Wells. You'll need a permit from the Wyoming State Engineer's Office, Ground Water Division, before drilling any domestic or stock well. The county helps by providing the application forms, but the permit itself comes from the state, not the county.

Utilities. Nothing requires you to hook up to grid power, gas, or municipal water/sewer in unincorporated Big Horn County. Off-grid solar, wind, or generator setups appear to fall under Wyoming's generally permissive state stance.

Bottom line: land use is loose here, but septic and wells are where the real paperwork lives, and it's always worth a call to confirm current fees and forms since those change.

Big Horn County in numbers

Worst-month sun
3.0 peak hours/day (4.7 annual average)
Heating degree days
7,461
Precipitation / snow
15.78 in / ? in a year
Elevation
4,072 ft
Hardware
The Home Depot · 6.8 mi
Supermarket
Warehouse Market · 6.8 mi
Hospital
Sheridan Memorial Hospital · 8.8 mi
Fire station
Sheridan Area Rural Fire Protection District · 6.2 mi

Open the full site report for this spot →

30-year climate normals for the nearest ZIP and distances from the town center; a specific parcel will differ. Run the site report on an address for its own numbers.

Planning a build in Big Horn County

The rules above decide what you may build. The numbers below decide what you will have to build, and they come from this place rather than from a national average.

Solar: size for the worst month, not the average

Big Horn County averages 4.7 peak sun hours a day across the year, but its worst month averages 3.0. That is a drop of about 37 percent. An array sized on the annual figure will therefore come up short in the worst month by roughly that much, in the season when lights, pumps, and heating fans all run hardest.

Put another way, meeting the same daily load in the worst month here takes about 1.6 times the array that the annual average implies, or a generator and the fuel budget to run it. Neither is wrong; what is wrong is discovering the gap in the first winter. The solar calculator runs this arithmetic against your own load list, and lesson four covers building that list before buying panels.

Heat: 7,461 heating degree days

That is a genuinely cold heating season, where losing heat for a few days in winter risks the plumbing and the building itself. Heating demand at this level dwarfs everything electrical in the house, which is why almost nobody here heats with electricity from a battery bank.

As a rough order of magnitude, a small, reasonably insulated cabin heated mainly with wood in a climate like this tends to burn in the region of 6.2 cords a season, with the real figure swinging widely on insulation, house size, and how you burn. Treat that as a bracket for planning your woodshed rather than a promise, split and stack a season ahead, and check with a moisture meter before burning. The firewood calculator and heat-loss calculator narrow it down from your own building.

Water: what the roof would actually catch

Big Horn County receives about 15.8 inches of precipitation a year. A 1,000 square foot roof here would shed on the order of 8,356 gallons a year at a realistic 85 percent collection efficiency, before any losses to first-flush diversion, evaporation, or overflow in a heavy storm.

The annual total is the easy part. What sizes a cistern is the longest dry stretch, because catchment is seasonal almost everywhere and a tank that covers the average year can still run empty in August. Check the local rules too: rainwater harvesting is regulated in some states even where it is broadly allowed. The rainwater calculator works from your own roof and rainfall pattern, and lesson three covers why water is chosen before power.

Distance is part of the plan

Measured straight line from the center of Big Horn County: the nearest fire station is about 6.2 miles away (Sheridan Area Rural Fire Protection District), the nearest hospital is about 8.8 miles away (Sheridan Memorial Hospital), the nearest supermarket is about 6.8 miles away (Warehouse Market). Road miles will be longer, and in winter longer again.

The fire distance is worth noting before you buy rather than at renewal: insurers commonly rate rural property partly on how far it is from a responding station and from a water source, and some decline off-grid or owner-built structures outright. Ask an agent who writes rural policies what they would need to see, while the answer can still change what you build. Lesson eleven covers the insurance and financing side.

The hospital distance sets what your first aid kit and your medical plan have to cover in the gap, and it is the number to think about before anyone in the household depends on refrigerated medication or mains-powered equipment.

Confirming this for your own parcel

On this page 3 of the eight topics are recorded as unclear or as varying within Big Horn County: building permits and codes, greywater, rainwater harvesting. Those are the calls to make first, because they are the ones where a general answer cannot be trusted for a specific parcel. Ask for the answer in writing where the office will give it, and note the name and the date where it will not.

Where a topic is recorded as settled here (zoning, what counts as a dwelling, septic and sewage, wells and water rights, mandatory utility connection), the source is cited further down this page. Sources go stale, ordinances get amended, and this site logs corrections publicly rather than editing them away, so if you find something here that no longer matches the county, the corrections page is how to say so.

Before any of those calls, walk the parcel with the land walk checklist and take the questions for the county with you. The parcel check pulls flood, wetland, slope, and access data for a specific parcel and shows its sources, which is a good way to arrive at the office with the questions already framed. Lesson two is the wider version of this list.

Looking at a specific parcel in Big Horn County, WY?The rules above are the jurisdiction. The land check runs the parcel itself: flood zone, soils and septic suitability, wetlands, slope, access, climate, and these verdicts, from a parcel number or coordinates.
Check a parcel →

Sources

Primary sources (statutes, agencies, municipal documents)

Secondary sources (universities, regional bodies)

Only government, statute, municipal, university, and regional-planning sources are listed. Pages used to find an issue but not to substantiate it are not cited. See how this database is researched.

Live here? Help keep Big Horn County accurate.

Residents, landowners, builders, and town officials: confirm what is right or tell me what is wrong. Every note is checked before it appears. Two minutes, no account.

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FAQ

Common questions about off-grid living in Big Horn County

Is it legal to live off-grid in Big Horn County, Wyoming?

There is no outright ban on living off-grid in Big Horn County, Wyoming - it is generally possible. Zoning and land use are generally allowed, putting a cabin, tiny home, or RV on raw land is generally allowed, and building permits are set locally and vary by area. Plan around septic/wastewater (restricted) and disconnecting from utilities (generally allowed). Because these rules are set locally, confirm the specifics with Big Horn County before you buy land or build.

Do I need a permit just to build a small off-grid cabin in unincorporated Big Horn County?

There's no county building code to meet, but you still need to file a Development Permit Application with the Land Planning Department so they can check for floodplain or airport zone issues.

Can I install a composting toilet instead of a septic system?

The county doesn't address composting toilets specifically in the sources I found, so I'd assume Wyoming DEQ oversight applies and call the Land Planning Department to confirm before you skip a septic permit.

Do I need a permit to drill my own well?

Yes, from the Wyoming State Engineer's Office, Ground Water Division, not the county. The county can hand you the application forms, but the state issues the permit.

Is off-grid solar or wind power restricted in Big Horn County?

Not that I could find. There's no county requirement to connect to grid utilities, and it appears to follow Wyoming's generally permissive stance on off-grid power.

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