Building permits, zoning and land rules in Fremont County, Wyoming

Unincorporated Fremont County does not require a general residential building permit for an ordinary home outside the county's special regulated areas¹. Fremont County has not adopted county-specific building codes; it recommends following the Wyoming-adopted codes for new construction, but does not describe them as county-adopted³. Development in a county-regulated floodplain requires a Floodplain Development Permit, and work cannot start until the Floodplain Administrator issues an Authorization to Construct². Certain public, commercial, assembly and other covered projects, including site plans for RV and camping parks, need Wyoming State Fire Marshal plan review³. Fremont County does not issue certificates of occupancy; a project under State Fire Marshal jurisdiction may need that office's certificate instead³. Inside Riverton and the county's other incorporated places, the city's own rules apply, not the county's¹.

Fremont County has no separate general residential building-permit office, because ordinary rural homes outside special regulated areas do not need a general county building permit¹. The Fremont County Planning Department handles building-code guidance, rural addressing, floodplain zoning, subdivision review and small wastewater work; call (307) 332-1077 or visit 450 North 2nd Street, Room 360, Lander, Wyoming 82520⁶. For land in a floodplain, the application goes to the Fremont County Floodplain Administrator, and a new building in a Special Flood Hazard Area needs an Elevation Certificate showing the lowest floor at least 1 foot above Base Flood Elevation². The county's published fee schedule, effective February 2023, lists a $500 floodplain development permit fee, $700 for a simple or regular subdivision application and a $95 to $100 address fee; the county lists a newer FY 2026 schedule we could not read, so confirm current amounts with Planning before filing⁴. Projects inside an incorporated city go to that city, and reservation zoning is administered by the Intertribal Business Council¹.

Fremont County does not have countywide zoning across ordinary unincorporated land³. Exceptions: county floodplain zoning covers FEMA-designated flood-hazard areas around Lander, Riverton, Dubois and Hudson, with the regulated areas viewable on the county website mapserver; incorporated cities run their own zoning and building codes; South Pass City has historic appearance zoning; and the Wind River Reservation is zoned Residential/Agricultural, administered by the Intertribal Business Council¹. Riverton zones its own land through its Community Development Department⁷. Outside those special areas, unincorporated Fremont County has no county minimum dwelling size or minimum residential lot size¹. The same ordinary areas have no countywide setback, lot-coverage or building-height standard, although septic, floodplain and subdivision rules can still shape a buildable site¹. Land divisions remain regulated even where zoning is absent⁸.

Fremont County requires a permit for every small wastewater system generating less than 2,000 gallons per day, and the Fremont County Planning Department runs that program¹. Wyoming DEQ handles high-strength commercial wastewater and residential systems above 2,000 gallons per day¹. The county recommends a pre-permit conference because soil conditions change substantially around the county¹. Only 29% of county soils are rated without severe limitations for a conventional drain field, so expect a site evaluation and possibly a nonconventional design⁹. On the county's published schedule, a new standard system permit is $575, a new nonconventional system $600, a replacement $525 and a new commercial system $750; an as-built permit for an unpermitted system is $2,000, so permit before you dig⁴. A Planning Department representative must inspect the system before backfilling, and the application requests 48 hours of notice when possible¹⁰. Inside the Town of Hudson, installing a small wastewater system also requires a permit to construct under state rules¹¹. Call the Small Wastewater Program at (307) 332-1077 before excavating⁶.

Fremont County has no countywide zoning ordinance on ordinary unincorporated land, so no county zoning district sets rules for RVs or tiny homes there³. We could not confirm a county rule on long-term RV living, temporary camping, tiny homes, manufactured homes or accessory dwellings, so ask the Fremont County Planning Department before you commit to one⁶. Any answer does not reach incorporated cities, South Pass City, the Wind River Reservation or county-regulated flood-hazard areas, which follow separate rules¹. Unincorporated land outside those areas has no county minimum dwelling size¹. A small residential wastewater system serving an occupied unit still requires county approval when it generates less than 2,000 gallons per day¹. We also could not confirm whether composting toilets, holding tanks, graywater systems or other off-grid sanitation methods satisfy Fremont County requirements, so ask the Planning Department before relying on an alternative system⁶.

1. Ask the Planning Department which authority covers the parcel, because incorporated cities, South Pass City, the Wind River Reservation and county-regulated flood-hazard areas follow different controls^1,6.

1. Check floodplain status before site work; development in an unincorporated Special Flood Hazard Area needs a permit, and work cannot begin before the Authorization to Construct is issued².

1. Arrange a small-wastewater pre-permit conference and obtain the required county septic permit before covered work starts¹.

1. Keep the septic excavation open for the required Planning Department inspection before backfilling¹⁰.

1. If the property needs a well, obtain an approved State Engineer permit before drilling⁵.

1. Confirm subdivision status and recorded access, especially for a recently divided tract⁸.

1. Wyoming does not issue a statewide general-contractor license, but local approvals can still apply and electrical work remains separately regulated¹².

Check legal access, subdivision history, water, septic feasibility and floodplain status before closing. Fremont County regulates subdivisions in unincorporated areas, while parcels of at least 35 acres generally need binding, recordable access and utility easements at least 40 feet wide to a public road unless properly waived⁸. Agricultural and family land-division exemptions are conditional, so verify that the proposed division and its documentation satisfy the applicable Wyoming rule⁸. A groundwater well needs State Engineer approval before drilling, and a typical domestic or stock application has a $50 filing fee⁵. Septic deserves early attention because only 29% of county soils are rated without severe limitations for a conventional drain field⁹. Federal land covers 57.7% of Fremont County, so verify legal access rather than relying on map appearance⁹. Typical effective property tax is about 0.6%, with a median annual bill near $1,591⁹.