Off-Grid Living in Teton County, Montana

Teton County, Montana (county seat Choteau) is one of the more open-feeling places in the state for off-grid living, mostly because it has no countywide zoning ordinance. But "no zoning" doesn't mean "no rules" - there's still subdivision regulation, floodplain review, septic permitting, and a state water-rights system that treats this county's river basin as closed. Here's what I found, dimension by dimension, and where the honest gaps are.

Zoning. The Teton County Planner's office confirms it issues letters on the "absence of zoning" in the county when asked, and administers the Subdivision Regulations, Growth Policy, and Floodplain Regulations instead of a use-based zoning code. So raw land use is largely unregulated at the county level, though any parcel could still be subject to floodplain rules or subdivision review depending on its history.

Dwellings, tiny homes, RVs. I couldn't find a Teton County-specific page addressing tiny homes or RV occupancy. Absent local rules, this falls back to the Montana state baseline: IRC Appendix Q covers foundation-built tiny homes, and tiny homes on wheels are typically treated as RVs under state law.

Building permits. Montana's state building code program generally exempts single-family homes from state permit jurisdiction unless a county has locally adopted the code. I didn't find an official Teton County building department page confirming local adoption for unincorporated areas, so this is genuinely unclear - confirm directly with the county Planning or Clerk's office before you build.

Septic and composting toilets. This is one area Teton County does regulate closely. The county Sanitarian's office explains that parcels under 20 acres generally need DEQ-approved wastewater and well siting, while parcels over 20 acres may have county-based approval depending on when the parcel was created. If no prior approval exists, a site evaluation is required, including a soil test pit of specific depth and width near the proposed drainfield. Composting toilets aren't separately addressed, so treat them as an alternative system needing sign-off from the Sanitarian or DEQ.

Greywater. No county-specific greywater rule turned up; I'd expect it to run through the same Sanitarian/septic permitting process under state DEQ rules.

Rainwater harvesting. Nothing in my research suggests a state or county prohibition on basic rooftop collection for personal, non-potable use.

Wells and water rights. Here's the twist: Teton County sits partly in a river basin that Montana closed to new surface water allocation back in the 1990s. That means new water use generally must be offset (mitigated) elsewhere. The statewide exempt-well threshold (10 acre-feet/year, 35 gpm max) still applies, but starting in 2026 well owners using the permit exception must file a Notice of Intent with DNRC beforehand. Well approvals on smaller parcels also get cross-checked by the County Sanitarian against DEQ records during septic permitting.

Utility disconnection. No ordinance found requiring or banning grid disconnection. In practice, septic and water approvals act as the real gatekeepers for habitability, not the electrical hookup itself.

Bottom line: zoning is refreshingly light here, but water and wastewater compliance are not optional, and the closed-basin status makes well permitting worth extra homework.