This is PermitBase’s published record for Unincorporated Jefferson County as of 2026-07-07. It has since been superseded — see the current record. A historical record reflects what PermitBase had verified at that time; it may not capture a real-world change the jurisdiction had made but PermitBase had not yet verified, and it includes any errors we later corrected. Snapshots are never edited retroactively.
Unincorporated Jefferson County building permits
VerifiedUnincorporated Jefferson County, Idaho — as published 2026-07-07.
Verified 2026-07-08 · Source
Codes adopted
2018 International Building Code (IBC) — adopted by Jefferson County Ordinance 2022-02, effective March 7, 20222018 International Residential Code (IRC) — adopted by Jefferson County Ordinance 2022-02, effective March 7, 2022
Permit types & fees
Residential Building Permit (Single-Family Dwelling / New Construction, Additions, ADUs)
VerifiedRequired for new single-family dwellings, additions, accessory dwelling units, remodels, and most accessory structures over 120 sq ft in unincorporated Jefferson County. Governed by the 2018 IRC as adopted by Ordinance 2022-02. Applications are submitted through the Jefferson County Planning, Zoning & Building Cityworks public portal; mechanical, electrical, and plumbing trade permits/inspections are handled separately by the Idaho Division of Occupational and Professional Licenses (DOPL), not the county.
Verified 2026-07-08 · Source
Requirements
- Building permit required for new single-family dwellings, additions, ADUs, remodels, and accessory structures exceeding 120 sq ft in unincorporated Jefferson County
- All construction must comply with the 2018 IRC
- Register for and activate an account on the Jefferson County Cityworks public portal (Chrome or Firefox browser required) before applying
- Submit Parcel Number, Parcel Size, County Zoning, Location Address/Subdivision info, flood zone status, full dimensional/square-footage data, and setback distances (N/E/W/S) as part of the online application
- Site Plan showing all property lines, setbacks, easements, North arrow, existing/proposed structures with dimensions, driveway location, and canals/rivers/roads
- Complete set of plans: floor plan(s) with room dimensions, footing/foundation details with steel requirements, truss layout, engineered truss design (stamped by an Idaho-licensed engineer), and all four building elevations
- Recorded warranty deed demonstrating ownership or authorization to build
- Idaho Contractor's License, or a completed Contractor Exemption form if owner-built
- Access Permit from Jefferson County Public Works (county roads) or Idaho Transportation Department (state highways)
- Septic Permit (approved) from Eastern Idaho Public Health, or an EIPH authorization-to-connect letter if tying into an existing/private sewer system
- If in a mapped flood zone: Flood Plain Development Permit and Elevation Certificate
- Mechanical (HVAC), electrical, and plumbing systems must be separately permitted and inspected by Idaho DOPL — not submitted as part of the county building permit package
- All required attachments must be individually labeled PDF files uploaded through the portal
Required documents
- RequiredSingle Family Dwelling Help Information (Date of Form: January 2, 2024)County checklist of information and documents needed before starting a single-family dwelling application in the Cityworks portal
- OptionalAccessory Dwelling Unit (ADU) Building Permit Application – Help Guide (Date of Form: June 26, 2025)County checklist specific to ADUs, including the 1,200 sq ft / 2-bedroom cap and required documents
- RequiredSite PlanScaled site plan showing property lines, setbacks, easements, structures, driveway, canals, and North arrow — see county Sample Site Plan resource
- RequiredComplete Set of Plans (Floor Plan, Truss Layout, Engineered Truss Design, Elevations)Full architectural/structural plan set uploaded as individually labeled PDF attachments in the Cityworks portal
- RequiredRecorded Warranty DeedProof of ownership or authorization to build on the parcel; obtained from the Jefferson County Clerk's Office if not already on hand
- RequiredIdaho Contractor's License or Contractor Exemption FormRequired for the contractor of record, or a completed exemption form for owner-builders
- RequiredAccess PermitFrom Jefferson County Public Works/Road & Bridge (county roads) or Idaho Transportation Department (state highways)
- RequiredSeptic Permit (or EIPH Authorization to Connect)From Eastern Idaho Public Health
- OptionalFlood Plain Development Permit and Elevation CertificateRequired only if the parcel is within a mapped flood zone
Fee schedule
| Fee type | Amount | Notes |
|---|---|---|
| Building permit fee — Total Valuation $1 to $500 | $26.46 | Jefferson County Fee Schedule 2026, Exhibit A (adopted 4-6-2026) |
| Building permit fee — Total Valuation $501 to $2,000 | $26.46 for the first $500, plus $3.30 for each additional $100 or fraction thereof | Jefferson County Fee Schedule 2026, Exhibit A |
| Building permit fee — Total Valuation $2,001 to $40,000 | $75.96 for the first $2,000, plus $12.13 for each additional $1,000 or fraction thereof | Jefferson County Fee Schedule 2026, Exhibit A |
| Building permit fee — Total Valuation $40,000 to $100,000 | $536.90 for the first $40,000, plus $9.92 for each additional $1,000 or fraction thereof | Jefferson County Fee Schedule 2026, Exhibit A |
| Building permit fee — Total Valuation $100,001 to $500,000 | $1,132.10 for the first $100,000, plus $7.71 for each additional $1,000 or fraction thereof | Jefferson County Fee Schedule 2026, Exhibit A |
| Building permit fee — Total Valuation $500,001 to $1,000,000 | $4,216.10 for the first $500,000, plus $5.52 for each additional $1,000 or fraction thereof | Jefferson County Fee Schedule 2026, Exhibit A |
| Building permit fee — Total Valuation $1,000,001 to $5,000,000 | $6,976.10 for the first $1,000,000, plus $3.30 for each additional $1,000 or fraction thereof | Jefferson County Fee Schedule 2026, Exhibit A |
| Building permit fee — Total Valuation $5,000,001 and over | $20,176.10 for the first $5,000,000, plus $2.20 for each additional $1,000 or fraction thereof | Jefferson County Fee Schedule 2026, Exhibit A |
| Manufactured Home — Single Wide | $250.00 | Jefferson County Fee Schedule 2026, Exhibit A |
| Manufactured Home — Double Wide | $500.00 | Jefferson County Fee Schedule 2026, Exhibit A |
| Manufactured Home — Triple Wide | $750.00 | Jefferson County Fee Schedule 2026, Exhibit A |
| Plan Review Fee | 15% of Building Permit Fee | Jefferson County Fee Schedule 2026, Exhibit A |
| GIS/Mapping Review Fee | $30.00 added to each application | Jefferson County Fee Schedule 2026, Exhibit A |
| Technology Fee | $30.00 added to each application | Jefferson County Fee Schedule 2026, Exhibit A |
| Inspection Fee | $90.00 | Jefferson County Fee Schedule 2026, Exhibit A |
| Re-Inspection Fee | $90.00 | Jefferson County Fee Schedule 2026, Exhibit A |
| Agricultural Exempt Building Permit | $250.00 | Jefferson County Fee Schedule 2026, Exhibit A |
Sources & verification
Verified against official sources. Last reviewed 2026-07-08.
Fee schedules
Applications & forms
Codes & ordinances
Department & other records
Fees, timelines, and adopted codes are researched from each jurisdiction's published records — see how we verify. Requirements change and vary by project, so always confirm the current details with the Unincorporated Jefferson County building department before you submit. PermitBase is an independent reference and is not affiliated with any government agency.