Accessory Residential Unit (ARU) in Unincorporated Teton County, Wyoming

Unincorporated Teton County requires an accessory residential unit (aru) permit for: No more than 1 ARU permitted accessory to a dwelling unit; ARU floor area is included in the maximum floor area/FAR calculation for the primary dwelling unit; Occupancy restricted to: (a) persons employed within Teton County per Teton County Housing Authority guidelines, OR (b) family members of the principal dwelling's occupants, OR (c) intermittent nonpaying guests of the family occupying the primary Detached Single-Family Unit; Minimum ARU rental period is 90 days; Outside storage limited to daily-travel vehicles; other possessions (recreational/secondary vehicles, boats, construction materials, etc.) must be stored in an enclosed structure; ARUs built after 6/4/2018 are deed-restricted as Workforce housing; ongoing compliance requires an annual Tenant Qualification Packet (Accessory Residential Unit Checklist, current Affidavit of Current Employment, Certification and Oath forms) submitted to the Teton County Housing Department. If your project isn't listed, confirm with Teton County Planning & Building Services Department — Building Division at 307-733-3959 (Building Official/fee estimates: 307-733-7030; Inspection Line: 307-732-5745) before starting work.

In Unincorporated Teton County, the published ARU construction permit fee is: No separate ARU permit fee; charged under the standard valuation-based Residential Building Permit fee schedule (ARU floor area included in total valuation). These are the jurisdiction's own published figures — see the fee schedule table and source citations on this page.

Plan review for an accessory residential unit (aru) permit in Unincorporated Teton County typically runs 5–20 business days. This is an estimate, not a published figure — confirm current review times with Teton County Planning & Building Services Department — Building Division at 307-733-3959 (Building Official/fee estimates: 307-733-7030; Inspection Line: 307-732-5745).

You'll need: Residential Building Permit application (standard — no separate ARU permit); Accessory Residential Unit Checklist; 2026 Affidavit of Current Employment; Certification and Oath — Tenant / Owner of Restricted Unit. See the required-documents checklist on this page for details on each.

Apply through Teton County Planning & Building Services Department — Building Division at 200 S. Willow Street, Jackson, WY 83001 (P.O. Box 1727, Jackson, WY 83001-1727). Phone: 307-733-3959 (Building Official/fee estimates: 307-733-7030; Inspection Line: 307-732-5745), email: permittech@tetoncountywy.gov. Office hours: Applications submitted through the Teton County Online Portal (SmartGov); New Residential Construction, Commercial New Construction, and Miscellaneous (under 500 sq ft) permits require a scheduled submission/take-in week booked via the Bookings page. Trade permits (mechanical, plumbing, demolition, re-roof) do not require a submission week and are typically issued within 48 hours.. Official information: https://www.tetoncountywy.gov/560/Building.

Unincorporated Teton County, Wyoming has adopted: 2024 International Building Code (IBC), including Appendix C (Group U-Agricultural Buildings) and Appendix I (Patio Covers) — Teton County Building Codes Resolution, effective February 1, 2025; 2024 International Residential Code (IRC), including Appendix BB (Tiny Houses) and Appendix AF (Radon Control Methods) — effective February 1, 2025; 2024 International Plumbing Code (IPC), including Appendix E (Sizing of Water Piping System); 2024 International Mechanical Code (IMC), including Appendix A (Combustion Air Openings and Chimney Connector Pass-Throughs); 2024 International Fuel Gas Code (IFGC), all appendices excluded; 2021 International Energy Conservation Code (IECC), all appendices excluded; 2024 International Existing Building Code (IEBC), including Appendix A (Guidelines for the Seismic Retrofit of Existing Buildings); 2024 International Property Maintenance Code (IPMC), applied only to the extent referenced provisions relate to fire and life safety; 2023 National Electrical Code (NEC) — enforced by the Electrical Division of the Jackson Hole Fire/EMS Department (Section 101.4.8 Electrical, County Building Codes Resolution); 2024 International Wildland-Urban Interface Code (IWUIC) — adopted jointly by the Town of Jackson and Teton County; enforced by Jackson Hole Fire/EMS. Local amendments apply — see the Unincorporated Teton County overview page for the full list.

No — an ARU is built under the standard residential building permit. It is, however, subject to Land Development Regulations Section 6.1.11.B use standards (occupancy, floor-area, rental-period restrictions) and, for units built after 6/4/2018, an ongoing Workforce deed-restriction compliance program administered by the Teton County Housing Department.