Bolthole Index

Cassia County, Idaho

Building permits, zoning and land rules in Cassia County, Idaho

53Index Score / 100
#30 of 44 in Idaho

Unincorporated Cassia County, Idaho requires a county building permit to construct, erect, relocate or remodel a covered building, including a one-story detached accessory structure over 200 square feet, subject to stated exceptions1. Cassia County zoning applies in the unincorporated areas, with a general 1-acre dwelling rule, and incorporated cities may have separate rules23. Septic permits for new and repaired systems come from South Central Public Health District, not the county's Zoning and Building Department4.

At a glance

Building permit
Required for covered construction, relocation and remodeling; detached accessory structures over 200 square feet also require permits, subject to stated exceptions1
Zoning
Yes; Cassia County publishes zoning regulations and an official zoning map5
Septic permits
South Central Public Health District issues permits for new and repaired systems4
Agricultural buildings
Building-code exemption may apply, but zoning placement requirements and permits still apply6
Minimum dwelling lot
Generally 1 acre in unincorporated Cassia County, with code, health-authority and approved-subdivision exceptions3
RV or tiny-home living
Not confirmed; ask Zoning and Building about the parcel and proposed occupancy7
Owner-builder exemption
Owners working on their own land may be exempt from contractor registration, but not from applicable permits or inspections89
Private well
An Idaho Department of Water Resources drilling permit is required before drilling10

Who to call

Building permits

Cassia County Zoning and Building Department

Building permits and inspections, zoning and land-use applications, agricultural siting, manufactured-home placement, temporary placement and floodplain development

208-878-7302

bldgdept@cassia.gov

Cassia County Courthouse, 1459 Overland Ave., Room 210, Burley, Idaho 83318

Online permits →

Septic permits

South Central Public Health District - Heyburn Office

Septic-system and land-development questions and permitting for Cassia County

(208) 678-8221

septic@phd5.id.gov

485 22nd Street, Heyburn, ID 83336

Online permits →

Contact details are copied from each office’s official page and were checked against it on October 9, 2026.

Off-grid gear

Going off-grid in Cassia County means bringing your own water and power. The kit we’d start with:

These are affiliate links — we may earn a commission, at no cost to you. As an Amazon Associate, Bolthole Index earns from qualifying purchases.

Do you need a building permit in Cassia County, Idaho?

Yes. Cassia County requires a permit to construct, erect, relocate or remodel a building covered by its adopted building code111. A one-story detached accessory structure over 200 square feet also requires a permit, subject to the county's stated residential-code exceptions1. Agricultural buildings defined by the building code can be exempt from the adopted building codes, but zoning placement requirements and permits still apply6. Manufactured and mobile homes need a placement permit before installation, and older units must meet the stated federal requirements12. Electrical, plumbing and HVAC work requires separate state permits13. County inspections include setbacks, footings, foundation, rough framing, energy, wall board and final stages, and requests require at least six business hours' notice14. Final county approval is required before a permitted structure is used or occupied15.

Who issues building permits in Cassia County, and how do you reach the Zoning and Building Department?

Cassia County Zoning and Building Department is the starting point for building permits, inspections and land-use questions7. The office is in the Cassia County Courthouse at 1459 Overland Ave., Room 210, Burley, Idaho 83318; call 208-878-7302 or email bldgdept@cassia.gov7. Cassia County publishes applications for building permits, accessory dwellings, manufactured-home placement, floodplain development, subdivisions, temporary placement and other land-use reviews16. A building application requires two plan sets covering the site, foundation or basement, floor plan, elevations, exterior and roof details, wall section, and window and door schedule or energy documentation13. Building-permit fees are calculated from square footage and the county's valuation table, and the county lists a $200 residential plan review fee and a $25 floodplain development permit fee; ask the department to confirm the current total before submitting17. Development in a Special Flood Hazard Area requires a floodplain development application before work begins18.

Does Cassia County have zoning, and who sets zoning rules in the cities?

Yes. Cassia County publishes zoning regulations and an official zoning map5. For dwellings in unincorporated Cassia County, the general minimum lot area is 1 acre, with county-code exceptions; the health authority can determine the minimum where groundwater or soil conditions warrant, and approved subdivisions with central sewer or water may qualify for smaller lots3. Outside subdivision lots, principal-building setbacks are generally 54 feet from the center of an adjoining street and 15 feet at the rear and interior side; the Industrial Commercial zone uses 5 feet at the rear and interior side19. Accessory-building placement is different, so confirm the parcel's district and proposed structure with Zoning and Building19. Building-height limits also vary by zoning district20. County zoning regulations apply in unincorporated Cassia County, and incorporated municipalities may have separate rules, so ask the relevant city for zoning approval and building permits if the parcel is inside city limits2; we could not confirm who handles septic permits inside city limits beyond the district's service area, so call South Central Public Health District. Anyone dividing unincorporated land should consult Planning and Zoning before preparing plats or plans21.

Who issues septic permits in Cassia County, and how do they work?

South Central Public Health District serves Cassia County and reviews applications for new and repaired septic systems422. The district's Heyburn office is at 485 22nd Street, Heyburn, ID 83336; call (208) 678-8221 or email septic@phd5.id.gov23. Idaho's public health districts administer the statewide individual and subsurface sewage-disposal rules under an agreement with the Department of Environmental Quality24. A septic system cannot receive wastewater until the required final installation inspection occurs, and inspection preparation can require at least 48 hours' notice excluding weekends and holidays25. Only 26.7% of Cassia County soils are rated without severe limitations for a conventional septic drain field, so evaluate the actual homesite early26. If public or central wastewater treatment is reasonably accessible, the permitting authority may deny an onsite-system permit27.

Can you live in an RV or tiny home on your land in Cassia County?

We could not confirm a general Cassia County rule allowing or prohibiting residential or long-term RV occupancy on private land. Ask the Zoning and Building Department about the parcel's district, the proposed length and purpose of occupancy, and whether a temporary-placement permit applies7. We also could not confirm the operative county rules for tiny-home occupancy or a general minimum dwelling floor area. A small dwelling still has to fit the county zoning, building-permit and septic requirements5122. A manufactured or mobile home has a defined route: Cassia County requires a placement permit before installation, and zoning controls also apply12. Manufactured-home installations must be inspected and approved before occupancy28. Cassia County publishes an accessory-dwelling application, but the specific allowance and limits should be confirmed with Zoning and Building16.

Building a home in Cassia County: what are the steps, in order?

  1. Ask Cassia County Zoning and Building to confirm the zoning district, minimum lot area, setbacks, allowed use and floodplain status before choosing a house location531918.
  1. Contact South Central Public Health District early for septic review, because the district issues the septic permit and much of the county's soil is rated severely limited for a conventional drain field426.
  1. If the project needs a private well, obtain the Idaho Department of Water Resources drilling permit and use a licensed well driller10.
  1. If access connects to a state highway, obtain an Idaho Transportation Department encroachment permit before work in the highway right-of-way29.
  1. Submit two sets of the required building plans, confirm the current fees, and obtain separate state permits for electrical, plumbing and HVAC work1330.
  1. Schedule the county building inspections at least six business hours ahead, and complete final building and septic approvals before occupancy or wastewater discharge141525.

What should you check before buying land in Cassia County?

Start with legal buildability: have Cassia County Zoning and Building confirm the zoning district, allowed dwelling type, setbacks, lot-size exceptions and whether the proposed homesite lies in a Special Flood Hazard Area531918. Check wastewater feasibility before closing, because only 26.7% of county soils are rated without severe limits for a conventional septic drain field26. For an undeveloped parcel, verify a legal and practical water source; Idaho requires a drilling permit before a well is drilled10. Annual precipitation averages 16.2 inches, and severe drought occurs in 15.8% of years, making water planning a central purchase question3132. Federal land makes up 52.8% of Cassia County, so verify boundaries and recorded access rather than assuming adjoining public land provides access33. A driveway connecting to an Idaho state highway needs an encroachment permit29. The effective property-tax rate is about 0.4%, with a median annual bill of $1,1413435.

Watch-outs

  • Agricultural buildings can be exempt from the adopted building codes, but zoning placement requirements and permits still apply6.
  • Idaho's owner-builder exemption concerns contractor registration, not applicable county permits or inspections89.
  • Development in a Special Flood Hazard Area needs a floodplain development application before work begins18.

Sources

  1. Cassia County Idaho - Permit Information, quoted and re-checked
  2. Cassia County Idaho - Permit Information, quoted and re-checked
  3. Cassia County Idaho - Permit Information, quoted and re-checked
  4. phd5.idaho.gov, quoted and re-checked
  5. Cassia County Idaho - Zoning Maps, quoted and re-checked
  6. Cassia County Title 11, Chapter 1 - Building Code, quoted and re-checked
  7. Cassia County Zoning and Building Department (cassia.gov)
  8. Frequently Asked Questions (FAQ) - Division of Occupational and Professional Licenses (Idaho statewide rule), quoted and re-checked
  9. How To Purchase a Trade Permit (Idaho statewide rule), quoted and re-checked
  10. Wells Overview (Idaho statewide rule), quoted and re-checked
  11. Cassia County Title 11, Chapter 1 - Building Code, quoted and re-checked
  12. Cassia County Idaho - Permit Information, quoted and re-checked
  13. Cassia County Building Permit Application, quoted and re-checked
  14. Cassia County Idaho - Permit Information, quoted and re-checked
  15. Cassia County Building Permit Application, quoted and re-checked
  16. Cassia County Planning & Zoning Forms & Applications, quoted and re-checked
  17. Cassia County Idaho - Administrative Fees, quoted and re-checked
  18. Cassia County Code Title 12 - Flood Damage Prevention, Chapter 4, quoted and re-checked
  19. Cassia County Title 9, Chapter 8 - Regulations Within Zones, quoted and re-checked
  20. Cassia County Title 9, Chapter 8 - Regulations Within Zones, quoted and re-checked
  21. Cassia County Title 10, Chapter 3 - Preliminary Plat, quoted and re-checked
  22. phd5.idaho.gov, quoted and re-checked
  23. South Central Public Health District - Heyburn Office (phd5.idaho.gov)
  24. Septic and Septage (Idaho statewide rule), quoted and re-checked
  25. IDAPA 58.01.03 Individual/Subsurface Sewage Disposal Rules (Idaho statewide rule), quoted and re-checked
  26. Share of soils USDA rates "not limited" for a conventional septic drain field (SSURGO). A strict rating: the median county is about 6% and a tenth of counties are 0%, so a low figure means most lots need a site evaluation or an engineered system, not that septic is impossible. Cite it only with that caveat: Bolthole Index county data
  27. IDAPA 58.01.03 Individual/Subsurface Sewage Disposal Rules (Idaho statewide rule), quoted and re-checked
  28. Building Archives - Division of Occupational and Professional Licenses (Idaho statewide rule), quoted and re-checked
  29. Types of Right-of-Way Encroachment Permits (Idaho statewide rule), quoted and re-checked
  30. Cassia County Idaho - Administrative Fees, quoted and re-checked
  31. Annual precipitation: Bolthole Index county data
  32. Share of years in severe drought: Bolthole Index county data
  33. Federal land share: Bolthole Index county data
  34. Effective property tax rate: Bolthole Index county data
  35. Median property tax bill: Bolthole Index county data

Written October 9, 2026 from the rules quoted below, each taken from an official source and re-checked by an independent reviewer. This is research, not legal advice: rules change, so confirm with the office before you buy or build.

Found land here? Start a Property Hunt →

Compared with neighboring counties

Like all 6 of its neighbors, Cassia County requires a building permit for a home.

RuleCassia CountyJerome CountyMinidoka CountyTwin Falls CountyPower CountyLincoln CountyOneida County
Building permitRequiredRequiredRequiredRequiredRequiredRequiredRequired
County zoningYesYesYesYesYesYesYes
Septic permitsSouth Central Public Health DistrictSouth Central Public Health DistrictSouth Central Public Health DistrictSouth Central Public Health DistrictSoutheastern Idaho Public HealthSouth Central Public Health DistrictSoutheastern Idaho Public Health

County locator

Cassia County in Idaho

53
County map
Cassia County highlighted among the Idaho counties · colored by Index score

How Cassia County scores

Seclusion80100% ev.
Self-Sufficiency26100% ev.
Admin Boringness3890% ev.
Durability45100% ev.
Property Autonomy90100% ev.
Carry Cost77100% ev.

Evidence strength: 98%. This reports direct-source completeness and fallback use; it is separate from the score and is not a confidence interval. How it works →

$354kTypical home
0.4%Property tax
$4,486Land / acre
16.2"Annual rain
15.8% of yrsSevere drought
3.2 / yr (+3)Mid-century 100°F days
29.3 daysMid-century dry spell
0.86" (+7.2%)Mid-century 1-day rain
1.16×Wildfire change factor
100%Forward climate coverage
$1,259Home insurance / yr
6.1% / yrInsurance growth
1.1%Nonrenewal rate
county median (2+ published ZIPs)Insurance basis
637,984People within 2 hr
2,794Radius comparison (15 mi)
10People / sq mi
52.8%Federal land
62.2%Land at 15% slope or less
26.7%Soils rated "not limited" for septic (strict USDA rating)
428,237 acWorkable land screen
13%Wooded land
13.6 tonsBiomass / forest ac
46.5°FAvg temp

Scout Cassia County

Camp here before you commitBook a few nights nearby on Hipcamp →Already own land here?Earn money hosting campers — get $100 when you become a Hipcamp host →

Some links are affiliate or referral links — we may earn a commission, at no cost to you.

Property hunt

Find land. Bring the promising ones back.

Search live inventory elsewhere, then cost and vet each candidate here. No copied listings, account, or paid data feed.

View your full hunt →
ZillowLand & lotsRealtor.comLand listingsLandSearchRural & vacant land

Each button opens a current land search for Cassia County. Listing sites control their own results and filters.

Analyze a property
Add setup-cost allowances

Use rough quotes or placeholders. Blank fields count as $0.

Working estimate

—land + entered setup costs
Asking $ / acre
—
Setup allowance
—
All-in $ / acre
—

A planning estimate, not a valuation or contractor quote. The USDA benchmark includes farm land and buildings; it is context, not a parcel comp.

Before an offer

Parcel due diligence

0/8 checked

Saved properties and checklist progress stay on this device. Bolthole Index does not receive them.

Cities and towns in Cassia County

Inside a city or town, that city usually issues building permits and sets zoning; the county’s rules above cover unincorporated land. Septic, wells and floodplain rules usually stay with the county or state everywhere.

Not yet researched: Albion · Declo · Malta · Oakley

Answers from the rulebook for Cassia County

What the ordinances and state agencies actually say — one answer per question, each quoted from the official source and independently re-checked.

Cassia County rules

  • Building permitRequired

    Construction, erection, relocation, remodeling, and covered detached accessory structures in unincorporated Cassia County.

    • One-story detached accessory structures exceeding 200 square feet require permits, subject to 2012 IRC exceptions.
    • Agricultural siting permits apply to qualifying agricultural structures; a building permit is required if the structure is used for another purpose.
    • Manufactured or mobile homes require a placement permit before installation.

    detached accessory structure threshold: > 200 square feet (2012 IRC exceptions)

    “Building permits are required for any person, firm, or corporation desiring to construct, erect, relocate, or remodel a building covered under the terms of the International Building Code as adopted by the county (11-1-4, Cassia County Code)”
    2 more reviewed findings on this topic
    • Required — Construction, erection, relocation, or remodeling of buildings covered by the adopted International Building Code, and one-story detached accessory structures exceeding 200 square feet.
      “Building permits are required for any person, firm, or corporation desiring to construct, erect, relocate, or remodel a building covered under the terms of the International Building Code as adopted by the county (11-1-4, Cassia County Code)”
    • Required — Construction, erection, relocation, or remodeling of buildings covered by the adopted International Building Code, and one-story detached accessory structures over 200 square feet.
      “Building permits are required on any one-story detached accessory structure that exceed 200 square feet in overall floor area (see 2012 IRC for exceptions)”
  • Building code adoptedAdopted (with conditions)

    Buildings and structures subject to Cassia County building regulation.

    • The adopted versions are stated to be effective January 1, 2021.
    • Successive versions adopted or approved by Idaho may supersede the listed versions effective January 1 of the following year unless state statute requires a different date.
    • Agricultural buildings defined by the International Building Code are exempt from the adopted building codes but remain subject to zoning placement requirements and permits.
    “The County of Cassia, Idaho, hereby adopts and elects to enforce the provisions of the 2018 Edition of the International Building Code (IBC), including appendices E, G, H, and I;”
    One more reviewed finding on this topic
    • Adopted (with conditions) — Buildings covered under the International Building Code as adopted by Cassia County.
      “Building permits are required for any person, firm, or corporation desiring to construct, erect, relocate, or remodel a building covered under the terms of the International Building Code as adopted by the county (11-1-4, Cassia County Code)”
  • InspectionsRequired

    County-regulated buildings and manufactured homes.

    • Inspection requests must be made at least six business hours in advance.
    • Listed building inspections include setbacks, footings, foundation, rough framing, energy, wall board/gypsum board, and project/energy final.
    • Manufactured-home inspections include setbacks, footings, foundation, block and tie-down, and final.

    advance notice: >= 6 business hours

    “INSPECTIONS REQUIRED BY BUILDING INSPECTOR”
    One more reviewed finding on this topic
    • Required — County building permit projects subject to Cassia County building inspection requirements.
      “INSPECTIONS REQUIRED BY BUILDING INSPECTOR Request for inspections must be given at least six (6) business hours in advance.”
  • Certificate of occupancyLimited

    Structures subject to the county building-permit application and final inspection process.

    • Approval/final inspection must be obtained before use or occupancy of the structure.
    • The application references revocation of a Certificate of Occupancy under IRC R110.5.
    • The cited source does not establish a universal certificate-of-occupancy requirement for every structure.
    “approval / final inspection will be obtained from the Cassia County Zoning & Building Department, prior to use and/or occupancy of structure for which permit is sought.”
  • County-wide zoningPresent

    Cassia County zoning regulation and zoning mapping.

    • The official zoning map is identified as adopted 02-05-2024.
    “Cassia County Official Zoning Map (Adopted 02-05-2024)”
    One more reviewed finding on this topic
    • Present (with conditions) — Cassia County zoning regulations in unincorporated county areas.
      “The minimum lot area for any dwelling unit, single- or multi-family, within the unincorporated areas of the county shall be one acre (see 9-4-2, of the Cassia County Code for exceptions)”
  • Zoning districtsPublished (with conditions)

    Cassia County zoning districts and official zoning map for county-regulated areas.

    • Cassia County publishes Title 9 zoning regulations, including establishment of zones and regulations within zones.
    • The official zoning-map page identifies the Cassia County Official Zoning Map as adopted February 5, 2024.
    • District-specific permissions and conditions may vary by zone and may not apply inside incorporated municipalities.

    official zoning map adoption date: 02-05-2024

    “Title 9 Zoning Regulations Chapter 1 - Title, Purpose, Declaration, Intent Chapter 2 - Definitions Chapter 3 - General Provisions Chapter 4 - Supplementary Regulations Chapter 5 - Enforcement and Administration Chapter 6 - Establishment of Zones Chapter 7 - General Purposes of Zones Chapter 8 - Regulations within Zones Chapter 9 - Performance Standards”
  • Minimum lot sizeSpecified

    Dwelling lots in unincorporated Cassia County.

    • The general minimum lot area is one acre.
    • The zoning table lists 43,560 square feet for the listed zones.
    • Exceptions apply under Cassia County Code 9-4-2.
    • In seasonal high subwater, low permeability, or shallow-soil areas, minimum lot size is determined by the health authority.
    • If central sewer or water is available, minimum lot size may be reduced in an approved subdivision.

    minimum lot area: 1 acre (See Cassia County Code 9-4-2 for exceptions) · minimum lot area: 43560 square feet (Zoning-table value; health-authority and approved-subdivision exceptions apply)

    “The minimum lot area for any dwelling unit, single- or multi-family, within the unincorporated areas of the county shall be one acre (see 9-4-2, of the Cassia County Code for exceptions)”
    One more reviewed finding on this topic
    • Specified — Any single- or multi-family dwelling unit in unincorporated Cassia County.
      “The minimum lot area for any dwelling unit, single- or multi-family, within the unincorporated areas of the county shall be one acre (see 9-4-2, of the Cassia County Code for exceptions)”
  • SetbacksSpecified

    Principal dwellings and buildings under Cassia County zoning regulations.

    • Front and street-side setbacks are measured from the center of the adjoining street.
    • Corner lots require 54 feet from the center of both roads.
    • The listed setbacks do not apply to subdivision lots.
    • Industrial Commercial interior side and rear setbacks are 5 feet; other listed zones are generally 15 feet.

    front setback: 54 feet (corner lots measured from center of both roads) · rear setback: 15 feet (IC zone requires 5 feet) · interior side setback: 15 feet (IC zone requires 5 feet)

    “See Cassia County Code 9-8-2 (these setbacks do not apply to subdivision lots) · Minimum Front & Street Side Setbacks (including corner lots) · 54 feet from center of the adjoining street. · Yard Rear & Interior Side Setbacks: · 15 feet (except in Industrial Commercial (IC) Zone—5 feet setback is required) · Accessory Buildings from other structures require at least 10 feet.”
    One more reviewed finding on this topic
    • Specified — Principal buildings and dwellings in unincorporated Cassia County zoning districts.
      “See Cassia County Code 9-8-2 (these setbacks do not apply to subdivision lots) · Minimum Front & Street Side Setbacks (including corner lots) · 54 feet from center of the adjoining street. · Yard Rear & Interior Side Setbacks: · 15 feet (except in Industrial Commercial (IC) Zone—5 feet setback is required)”
  • Lot coverageSpecified

    Buildings and structures in county zoning districts.

    • The specific percentage varies by zone and is governed by Title 9 and amendments.
    “Within each of the zones, the height, number of stories, and the size of buildings and structures, and percentage of lot that may be occupied, the size of yards, courts, and other open spaces, the density of population and the location and use of buildings, structures and land for trade, industry, residence or other purposes are hereby regulated and restricted as set forth in this title or as such may be amended.”
  • Building heightSpecified

    Buildings and structures in county zoning districts.

    • The specific height limit varies by zone and is governed by Title 9 and amendments.
    “the height, number of stories, and the size of buildings and structures”
    One more reviewed finding on this topic
    • Specified — Principal buildings in Cassia County zoning districts.
      “RA 35 feet 54 feet 15 feet 15 feet 54 feet NR 43,560 sq. ft. NR AR 35 feet 54 feet 15 feet 15 feet 54 feet NR 43,560 sq. ft. NR AP 75 feet 54 feet 15 feet 15 feet 54 feet NR 43,560 sq. ft. NR”
  • Manufactured homesLimited

    Manufactured or mobile-home placement and occupancy in Cassia County.

    • A placement permit is required before installation.
    • Manufactured homes must meet HUD requirements if manufactured before June 15, 1976.

    HUD cutoff date: < 1976-06-15 (manufactured homes made before this date must meet HUD requirements)

    “require a placement permit prior to installation”
    One more reviewed finding on this topic
    • Limited — Mobile or manufactured homes used as residences on a building site or in a trailer park under Cassia County Title 9.
      “All mobile home/manufactured home owners must obtain an installation permit before installing a home that will be used as a residence on a building site or in a trailer park.”
  • Who permits septicLocal

    Subsurface sewage disposal permitting and related environmental-health administration for Cassia County.

    • South Central Public Health District serves Cassia County and other listed counties.
    • The health district reviews applications and issues permits for new and repaired septic systems.
    “South Central Public Health District serves Blaine, Camas, Cassia, Gooding, Jerome, Lincoln, Minidoka, and Twin Falls counties.”
    One more reviewed finding on this topic
    • Local (with conditions) — Cassia County subsurface sewage disposal permitting and review administered by South Central Public Health District.
      “Must be obtained from the South Central District Health”
  • Septic permitRequired

    New and repaired subsurface sewage disposal systems in Cassia County.

    • Applications are reviewed and permits issued by South Central Public Health District.
    • The cited page does not state a general exception list.
    “Environmental Health Specialists review applications and issue permits for new and repaired subsurface sewage disposal systems (septic tanks).”
  • Septic inspectionRequired

    New or repaired septic systems in Cassia County under SCPHD jurisdiction.

    • The Director may require one or more inspections necessary to determine compliance.
    • The permittee must uncover or make available system components requested for inspection.
    • Advance notice of at least 48 hours is required when preparation is needed, excluding weekends and holidays.
    • No system may receive wastewater before final installation inspection and completion of as-built drawings.

    advance notice: >= 48 hours (excluding weekends and holidays when preparation is required) · as-built delivery: <= 30 days (after final inspection)

    “No system may receive wastewater until the Director conducts a final installation inspection”
  • Agricultural exemptionConditional

    Agricultural buildings as defined by the adopted International Building Code.

    • Agricultural buildings are exempt from the building code under Title 11, section 11-1-7.
    • Agricultural siting permits are issued for structures housing farm implements, hay, grain, poultry, livestock, or horticultural products.
    • Agricultural buildings may not be used for human habitation, public use, or specified employment involving processed agricultural products.
    “Agricultural buildings, as defined by the International Building Code, are exempt from the building codes adopted herein”
    One more reviewed finding on this topic
    • Conditional — Agricultural buildings as defined by the International Building Code.
      “Agricultural buildings, as defined by the International Building Code, are exempt from the building codes adopted herein but shall remain subject to placement requirements and permits established by zoning regulations.”
  • Subdividing landRegulated (with conditions)

    Subdivision of land in unincorporated Cassia County.

    • A preliminary plat must be submitted with the completed conditional-use application and fee.
    • County staff is allowed at least 40 working days for each submittal review.
    • Minor subdivisions may create up to and including four lots when the stated infrastructure and prior-division conditions are met.
    • Minor subdivisions do not require a public hearing or conditional-use permit but must comply with Title 9.

    minor subdivision maximum lots: <= 4 lots (No shared infrastructure or improvements other than qualifying water system or common driveway; prior division limit also applies) · staff review period: >= 40 working days (For each submittal)

    “Each person who proposes to subdivide land in unincorporated Cassia County shall consult with the planning and zoning department before preparing any plats, charts, or plans, in order to become familiar with the requirements of this title 10, title 9 and the comprehensive plan”
  • Building in a floodplainRequired

    Development activities within Special Flood Hazard Areas in Cassia County.

    • A floodplain development permit application must be made before any development activity in a Special Flood Hazard Area.
    • Applications require a scaled plot plan and proposed elevations, and may require floodproofing, foundation, utility, recreational-vehicle/temporary-structure, and watercourse information.
    • Other local, state, and federal permits must be received before floodplain permit issuance.
    • The permit is conditional upon starting construction within 180 days and expires 180 days after issuance unless extended at the floodplain administrator's discretion.

    permit commencement deadline: 180 days (May be extended at floodplain administrator discretion for circumstances beyond permittee control)

    “Application for a Floodplain Development Permit shall be made to the Floodplain Administrator prior to any development activities located within Special Flood Hazard Areas.”
  • Permit feesPublished (with conditions)

    County zoning, development, building, plan-review, floodplain, and manufactured-home placement applications.

    • Building permits are calculated based on square footage and the IBC 2003 Valuation Table 1.
    • Permit and plan-review fees are determined by Board resolution and generally must be paid before issuance.
    • Published administrative fees include residential plan review, commercial plan review, floodplain development, manufactured-home placement, subdivision, and zoning applications.

    residential plan review: 200 USD · commercial plan review: 500 USD · floodplain development permit: 25 USD · minor subdivision: 500 USD · standard subdivision base fee: 700 USD (plus $10.00 per lot)

    “Building Permit = calculated based on square footage, and IBC 2003 Valuation Table 1”
    One more reviewed finding on this topic
    • Published (with conditions) — Cassia County zoning, development, building, and floodplain permit fees.
      “Building Permit = calculated based on square footage, and IBC 2003 Valuation Table 1 Plan Review-Residential | $200.00 Plan Review-Commercial | $500.00 Floodplain Development Permit | $25.00”
  • Permit processPartial

    County zoning, building, floodplain, subdivision, manufactured-home, and related permit processes.

    • The county publishes online applications and forms, including required building plans, floodplain permits, subdivision applications, and manufactured-home placement applications.
    • The building permit application requires two sets of plans and a non-refundable plan-review fee.
    “Building Permit Application for Cassia County”
    One more reviewed finding on this topic
    • Published (with conditions) — Cassia County building permit applications and associated county zoning/building review in unincorporated areas.
      “15. REQUIRED SUBMITTALS: ** (two sets of plans that include the following are required with application) **”

Idaho rules that apply here

  • Owner-builder exemptionConditional

    Homeowners personally performing plumbing work on their own residential premises in Idaho.

    • The homeowner must own the residential property and personally perform the permitted work.
    • The homeowner permit is valid only for a primary or secondary residence and associated outbuildings.
    • Associated outbuildings must not be used for commercial purposes or rented by a tenant.
    • The homeowner must accept responsibility for all work performed.
    • All work must be inspected by the Division of Occupational and Professional Licensing.
    • A plumbing permit must be obtained by application to the Division.
    • The application must be submitted with payment.
    • The application form states that an additional $65 fee may be assessed if the location is not clearly provided by directions or an attached map.
    • The application was revised 8/17/2022; this revision date is not treated as an effective date.

    unclear-location fee: 65 USD (May be assessed if the location is not clearly given by directions or an attached map.)

    “I certify that I am the owner of the residential property and will personally perform the work covered by this permit.”
    4 more reviewed findings on this topic
    • Available — An owner performing their own construction work on the owner's own land in Idaho.
      “A: Any person who engages in a construction job with a dollar amount exceeding $2000.00 (materials & labor) and is not otherwise exempt (The exemptions are listed below); [...] Owners: Owners who do their own work on their own land and do not intend to sell the property within 12 months are exempt from registration.”
    • Conditional — An Idaho homeowner undertaking construction or trade work for which a state-administered permit process applies.
      “Public (Homeowners Only) [...] *Public: “Homeowner” is pre-selected. [...] Once payment is processed, you may choose “Request Inspection” and/or “Print Permit””
    • Conditional — Owners performing construction work on their own land in Idaho under the state contractor-registration system.
      “Owners who do their own work on their own land and do not intend to sell the property within 12 months are exempt from registration.”
    • Conditional — Homeowners personally performing electrical work on a primary or secondary residence and related outbuildings in Idaho.
      “Homeowners may purchase a permit only when they themselves are doing electrical work on their primary or secondary residence and/or related outbuildings.”
  • Camping on your landLimited

    Camping or parking a vehicle or trailer on Idaho Fish and Game Wildlife Management Areas and access sites separate from a WMA.

    • The restriction applies in areas posted against camping or parking.
    • Leaving an unattended camp, vehicle, or trailer for more than 48 hours is prohibited without authorization.
    • Camping or parking for more than 10 days during any 30-day period on one WMA or one separate access site is prohibited without authorization.
    • The rule permits authorization by the Commission, Director, Regional Supervisor, or designee.

    unattended duration: > 48 hours (Unless specifically authorized by the Commission, Director, Regional Supervisor, or designee.) · camping or parking duration: > 10 days during any 30-day period per WMA or separate access site (Unless specifically authorized by the Commission, Director, Regional Supervisor, or designee.)

    “camp or park a vehicle or trailer for more than ten (10) days during any thirty (30) day period”
  • Accessory dwellingsLimited

    Accessory dwelling units for Idaho DEQ wastewater-flow and septic-system sizing purposes; this claim does not establish statewide zoning permission.

    • An ADU is sized as a single-family dwelling for the cited wastewater-flow guidance.
    • An ADU may combine flows with another structure into one system.
    • Any common septic tank must be large enough to hold the required capacity from both structures.
    • Local land-use, building, and septic authorities may impose additional requirements.

    wastewater flow basis: single-family dwelling

    “Size as a single family dwelling. Can combine with another structure's flows into one system”
  • Well permitRequired

    Construction or drilling of wells in Idaho, including domestic wells.

    • Before drilling, the well owner or driller must obtain a drilling permit from IDWR.
    • All wells must be constructed by a well driller with a valid IDWR license.
    • The separate water-right permit exemption for domestic purposes does not eliminate the drilling-permit requirement.
    • For new diversions in qualifying subdivisions filed on or after July 1, 2025, a water-right permit is required in a moratorium area, critical groundwater area, or groundwater management area, except for in-home uses and watering livestock.
    • Well construction rules apply to wells and other artificial openings more than 18 vertical feet below land surface.

    well depth threshold: > 18 vertical feet below land surface (The cited well-construction rules describe covered wells and artificial openings.) · subdivision application date: >= 2025-07-01 (Applies to qualifying new diversions described in Idaho Code § 42-227(4).)

    “Prior to drilling a well, the well owner or well driller must first obtain a drilling permit from IDWR.”
  • Mandatory utility hookupConditional

    Proposed individual or subsurface sewage disposal systems where public or central wastewater treatment facilities may be available.

    • The Director may deny a septic permit when public or central wastewater treatment facilities are reasonably accessible.
    • The cited rule does not establish a universal statewide requirement to connect every property to public sewer.
    • Subsurface septic discharge remains an identified onsite disposal method.
    “Public or central wastewater treatment facilities are reasonably accessible.”
  • Driveway accessRequired

    Private and public driveways or streets connecting to Idaho state highway right-of-way.

    • An ITD encroachment permit is required for private and public approaches, including driveways and streets.
    • No activity may occur on state highway rights-of-way until the Department or a delegated local highway agency issues an approved permit, except emergency approval affecting highway operations and motorist safety may precede processing.
    • A Traffic Impact Study may be required for new or expanded development seeking direct access to a state highway when the stated thresholds are met, unless waived by the District Engineer.

    peak-hour trips for possible TIS requirement: >= 100 new trips (unless waived by the District Engineer) · daily traffic for possible TIS requirement: >= 1000 vehicles per day (unless waived by the District Engineer)

    “Encroachment permits approved by the Department are required for private and public approaches (driveways and streets), utilities and other miscellaneous encroachments.”
  • Campground & park staysLimited

    Temporary camping in Idaho State Parks administered by the Idaho Department of Parks and Recreation.

    • Camping is permitted only in designated areas.
    • Stays are limited to 14 nights in a 30-day period; the same page's FAQ separately states a 15-day limit, creating an unresolved internal discrepancy.
    • Individual-site occupancy is limited to one family unit or no more than 8 persons unless otherwise specified; companion-site and site-design restrictions apply.
    • Camping is not permitted on beaches, parking lots, or day-use facilities.
    • Check-in is at 2 p.m. for campsites and checkout is at 1 p.m.; late checkouts may incur additional fees unless prior arrangements have been made.

    state-park stay limit: 14 nights in 30 days (FAQ on the same page states 15 days in any 30-day period) · individual-site people limit: <= 8 people (one family unit or site-specific limits may apply)

    “Camping is permitted only in designated areas. [...] Stays are limited to 14 nights in a 30-day period.”
  • county zoning authorityGeneral

    Idaho counties adopting zoning for unincorporated areas through their boards of county commissioners.

    • A board of county commissioners is a governing board and may exercise the powers authorized by the Local Land Use Planning Act.
    • The county board's powers under the chapter apply to the unincorporated area of the county.
    • Zoning must be adopted, amended, or repealed by ordinance using the notice and hearing procedures in Idaho Code § 67-6509.
    • Zoning districts must conform to the adopted comprehensive plan.
    • Within zoning districts, standards may regulate or restrict building height, number of stories, size, construction, reconstruction, alteration, repair or use of buildings and structures; lot occupancy; courts, yards and open spaces; population density; and building and structure location and use.
    • Standards must be uniform for each class or kind of building throughout each district, but may differ between districts.
    • Overlay zoning districts require clear and objective standards and must not constitute a regulatory taking under Idaho or federal law.
    “The powers of the board of county commissioners conferred by this chapter shall apply to the unincorporated area of the county.”
  • county building authorityGeneral

    Idaho counties' authority to adopt and enforce building codes and require permits for residential construction in unincorporated areas when the county operates a building-code enforcement program.

    • The statute defines local government as any city or county of Idaho.
    • A local government that had not previously implemented a code-enforcement program may elect to implement one by ordinance evidencing its intent to do so.
    • Construction in a local-government jurisdiction enforcing building codes requires a permit under the applicable local ordinance.
    • A local government issuing permits and performing enforcement must adopt the specified state-adopted codes and may amend them only within the limits stated in Idaho Code § 39-4116(4).
    • Local amendments must generally provide at least an equivalent level of protection; accessibility amendments are restricted, and additional residential-code amendments require the statutory good-cause, necessity, ordinance, public-hearing, publication, and notice procedures.
    • Single-family homes and multiple-family dwellings up to two units are exempt from automatic fire-sprinkler requirements in the enumerated codes.
    • Agricultural buildings must be exempted; a county may issue farm-building permits only for road setbacks and utility easements, at no more than actual issuance cost.
    • Permits are governed by the laws in effect when the application is received.
    • The state division retains jurisdiction for in-plant inspections and installation standards for manufactured or mobile homes and for in-plant inspections and enforcement of modular-building and commercial-coach construction standards.
    “"Local government" means any city or county of this state.”

Still unanswered

We looked and could not find an official answer yet. Silence is not permission — ask the county directly.

  • Local zoning — Whether incorporated municipalities and other local authorities within Cassia County have independently adopted zoning controls.
  • Minimum dwelling size — Minimum floor area of dwelling units.
  • Living in an RV — Residential or long-term recreational-vehicle occupancy on private land.
  • Tiny homes — Tiny-house occupancy in Cassia County.
  • Off-grid sanitation — Off-grid sanitation and non-septic sanitation systems in Cassia County.
1 more unanswered
  • Short-term rentals

Each answer was extracted from an official source and independently re-checked against that source by a second reviewer. That is an evidence check, not legal advice. Rules change; confirm with the authority before you buy or build.

Water rights & wells in Cassia County

Whether a new home can legally get its own water here — the sub-state groundwater regime, from Idaho’s water agency.

Over-appropriated / declining

The aquifer here is over-appropriated and declining. A domestic well is usually still permit-exempt, but long-term supply is a genuine risk.

Household wellExempt — no permit or water right

Groundwater for domestic purposes up to 13,000 gpd is exempt from permitting; critical-area and moratorium closures generally target new PERMITTED (non-exempt) appropriations, so a household can still drill a domestic-exempt well even inside a critical groundwater area.

Limit: 13,000 gpd (homes, stockwater, irrigation of ≤0.5 acre) under Idaho Code 42-227

Idaho Dept of Water Resources — Domestic Exemption ↗

Prior-appropriation state (first in time, first in right). Groundwater rules change and basin boundaries follow the aquifer, not the county line — confirm current well and appropriation rules with the Idaho state water agency before you buy or drill.Groundwater governance as of Jul 2026, cited to each administering agency.

Living off-grid in Cassia County, Idaho

Is Cassia County a good place to live off-grid or homestead?

Cassia County scores 53/100 on the Bolthole Index, a solid county profile. Its strengths: a stronger property-autonomy legal backdrop and sparse surroundings — about 2,794 people within 15 miles. Watch-outs: thin water margin (16.2″/yr rainfall) and more administrative friction around building and land use.

Do you need a building permit in Cassia County, Idaho?

Cassia County generally requires a residential building permit, and it enforces county zoning. Onsite septic is permitted by South Central Public Health District (District 5). Owner-builders may act as their own contractor to build their home. These answers are quoted from official sources and independently re-checked. Rules change and cities within the county differ — always confirm with the county before you buy or build.

How much does land cost in Cassia County, Idaho?

Land in Cassia County runs about $4,486 per acre, based on the latest county data.

What is the water situation in Cassia County?

Cassia County gets about 16.2" of rain a year, with severe drought in roughly 15.8% of years. On water rights, Cassia County lies in the Eastern Snake Plain Aquifer (ESPA) Ground Water Management Area — Designated a GWMA (2016); the Snake River Basin Moratorium (2022, amended 2024) bars new/pending permit applications above Swan Falls Dam, effectively closing new appropriative groundwater rights — domestic-exempt wells excepted..

How remote is Cassia County?

A typical private-land location has about 2,794 people within 15 miles and 1,201,526 within 100 miles. These radius catchments are the published fallback where road routing is unavailable.

How Cassia compares in Idaho

Compare side-by-side →See all 44 Idaho counties ranked →