Bolthole Index

Mills County, Iowa

Building permits, zoning and land rules in Mills County, Iowa

56Index Score / 100
#40 of 99 in Iowa

Unincorporated Mills County, Iowa requires a building permit for construction from Mills County Building & Zoning, with a conditional exemption for qualifying agricultural buildings.12 The county applies its own zoning on unincorporated land, while Mills County Environmental Health issues septic permits and inspects systems before and after construction.345 Inside a city, confirm building requirements with city officials.6

At a glance

Building permit
Required for construction in unincorporated areas; qualifying agricultural buildings are conditionally exempt12
Zoning
County zoning applies in unincorporated areas, with district-specific standards37
Septic
A county permit and pre- and post-construction inspections are required45
Private well
A permit is required through the Mills County Board of Health or its agent8
Owner-builder
Owner may act as general contractor only at the Building Official's discretion; county permits and inspections still apply910
RV or tiny home
Occupancy rules were not confirmed; ask Building & Zoning about the parcel and proposed use311
Lot size and setbacks
AG and AR need 2 acres, LH 3 acres; AG, AR and LH setbacks are 75 ft front, 10 ft side, 25 ft rear1213
County-road entrance
A county permit is required for each entrance on a county-jurisdiction road14

Who to call

Building permits

Mills County Building & Zoning

Building permits, zoning applications, parcel-use questions and county construction-code questions

712-527-4347

buildingsafety@millscountyiowa.gov

403 Railroad Avenue, Glenwood, IA 51534

Online permits →

Septic permits

Mills County Environmental Health Office

Septic and private-well permits and inspections in Mills County

712-527-9699 Option 4

eh@millscountyiowa.gov

Online permits →

Roads & driveways

Mills County Engineer / Secondary Roads

County-road entrance applications and county floodplain-development application forms

712-527-4873

engineer@millscountyiowa.gov

305 Railroad Avenue, Glenwood, IA 51534

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

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Do you need a building permit in Mills County, Iowa?

Yes. Unincorporated Mills County requires a building-permit application for construction, and the Building Official receives applications, reviews construction documents and issues permits.115 The county administers adopted codes that include the 2024 International Building Code and 2024 International Residential Code, along with adopted mechanical, plumbing, electrical, fuel-gas, existing-building, energy-conservation and property-maintenance codes.16 Work begun before the necessary permit is issued can bring an investigative fee and a county infraction, and a permit is not valid until its fees are paid.17 Construction documents must be submitted in writing, and the Building Official retains a set.15 Each residential construction phase must be inspected by a licensed and certified agency, contractor or individual; the county Building Official does not conduct those inspections for permits issued after July 16, 2021.18 Submit the resulting written compliance reports or certificates before seeking a certificate of occupancy.18 A farmhouse or other farm building primarily adapted to agricultural purposes is conditionally exempt from the county building code while used, or being built, for that purpose; the exemption does not itself remove zoning, septic, floodplain or subdivision requirements.2 Utilities may not be connected to a building that needs a permit until a licensed and certified agency, contractor or individual has inspected the work.19

Who is the Mills County building department, and how do you reach it?

Mills County Building & Zoning is the first call for a project on unincorporated land. The office is at 403 Railroad Avenue, Glenwood, IA 51534; call 712-527-4347 or email buildingsafety@millscountyiowa.gov.11 The county publishes its building-permit application through that department.11 If the parcel is inside city limits, the county page directs applicants to confirm requirements with city officials instead.11 Building-permit fees follow the county's fee schedule adopted by resolution, and electrical permits come from the Iowa Department of Public Safety rather than the county.20 For septic and well work, contact the Mills County Environmental Health Office at 712-527-9699 Option 4 or eh@millscountyiowa.gov; the office states that online septic permits do not apply.21 For an entrance on a county road, contact Mills County Engineer / Secondary Roads at 305 Railroad Avenue, Glenwood, IA 51534, phone 712-527-4873 or engineer@millscountyiowa.gov.22

Does Mills County have zoning?

Yes. Mills County zoning applies within the county's planning jurisdiction on unincorporated land; incorporated municipalities may impose separate requirements.7 Before designing, ask Building & Zoning to confirm the parcel's district, allowed use and dimensional standards.11 Minimum lot size for a conventional home is 2 acres in the AG and AR districts and 3 acres in LH, and the OS district requires a quarter-quarter section.12 In the AG, AR and LH districts the minimum front yard is 75 feet, the side yard 10 feet and the rear yard 25 feet; OS requires a 100-foot front yard.13 Maximum building height is 35 feet in AG, AR and LH and 25 feet in OS.23 Maximum building coverage is 5% in AG, 15% in AR and 5% in LH.24 Planned unit developments may vary these standards.25 Iowa generally removes qualifying agricultural land and structures from county zoning while they remain primarily adapted to agricultural use, except that floodplain regulation can still apply.26 Mills County's building-code agricultural exemption is similarly tied to actual agricultural adaptation and use, so confirm eligibility with Building & Zoning rather than assuming every rural outbuilding qualifies.211

How do septic permits work in Mills County?

Mills County Environmental Health issues permits to construct or repair septic systems, and every such project requires a permit.274 The county inspects septic systems before and after construction to verify both location and construction.5 Contact Environmental Health before finalizing the house site because only about 28.5% of mapped Mills County soils are rated without severe limitations for a conventional septic drain field; that rating does not prohibit a system, but it makes site evaluation and design an early priority.28 Iowa shares private-sewage oversight between county boards of health and the Department of Natural Resources, with counties required to enforce standards at least as stringent as state standards.29 A qualifying ownership transfer also requires a certified septic inspection before transfer, subject to statutory exceptions, and that inspection is valid for 2 years.30

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

Mills County's specific rule for long-term RV occupancy or temporary camping on private land could not be confirmed, so ask Building & Zoning about the parcel's district, proposed duration, utilities and sanitation before relying on an RV as housing.311 A county-specific tiny-home occupancy rule and minimum dwelling floor area also could not be confirmed.3 A manufactured home has a clearer route: in unincorporated Mills County it may be placed where single-family dwellings are permitted if the county's conditions are met, including removal of transport gear, an approved permanent foundation and direct utility connections.31 Iowa law also prevents a county from rejecting a residential structure solely because it is manufactured, while allowing the same foundation, setback and minimum-square-footage standards applied to a site-built single-family dwelling on the same lot.32 Ask Environmental Health how any proposed occupancy will obtain approved sanitation.21

Building a home in Mills County: the steps, in order

  1. Ask Mills County Building & Zoning to confirm the parcel's zoning district, residential use, lot standards and setbacks.311
  2. Contact Environmental Health for septic and private-well permitting before fixing the house location; both types of work require county authorization.48
  3. Secure a county-road entrance permit from Secondary Roads when access connects to a road under county jurisdiction.1422
  4. File the county building-permit application and written construction documents with Building & Zoning.15
  5. Arrange qualified third-party inspections for each residential construction phase and submit written compliance reports or certificates.18
  6. Ask Building & Zoning what occupancy documentation applies to the project; the county's reviewed commercial process requires specified verification before a certificate is issued, but the same requirement was not confirmed for every residence.3311
  7. An owner doing work on their own property is exempt from state contractor registration, not from county permits or inspections.10 A building permit is issued only to a State Registered General Contractor unless the Building Official allows the owner to act as general contractor, so ask before you apply.9

What should you check before buying land in Mills County?

Confirm the zoning district and development type first because Mills County's minimum lot size, yards and maximum building height vary by district.253435 Evaluate septic feasibility before choosing a homesite: about 28.5% of mapped soils are rated without severe limitations for a conventional drain field, even though about 91.9% of county land has a slope of 15% or less.2836 Ask Environmental Health about a well permit before drilling.8 Check mapped floodplain with the county before development; Secondary Roads publishes the county's floodplain-development application.22 If a seller is splitting land, property splits, line adjustments and subdivisions go through county plat review, and an agricultural split that does not change land use is exempt only from the sewer, septic and water requirements.37 Verify legal access because each entrance onto a public road under county jurisdiction needs a county permit.14 For budgeting, the effective property-tax rate is about 1.5%, the median annual property-tax bill is about $3,334, and USDA census farmland value is about $8,944 per acre.383940 The nearest city of 100,000 or more is about 27 miles from the county center.41

Watch-outs

  • Mills County does not perform the required residential phase inspections itself for permits issued after July 16, 2021; arrange qualified inspectors and submit their written compliance records.18
  • A county-road entrance requires its own permit, separate from building and zoning approval.14
  • Mills County's RV-living, temporary-camping, tiny-home and minimum-dwelling-size rules could not be confirmed; ask Building & Zoning before buying for one of those uses.11

Sources

  1. Chapter 24 Code of Ordinances (2026 county census)
  2. Chapter 24 - Building and Property Maintenance, quoted and re-checked
  3. Chapter 27 - Zoning Ordinance (2026 county census)
  4. Environmental Health, quoted and re-checked
  5. Environmental Health, quoted and re-checked
  6. Chapter 27 - Zoning Ordinance, quoted and re-checked
  7. Chapter 27 - Zoning Ordinance, quoted and re-checked
  8. Chapter 15 - Construction and Abandonment of Private Water Wells, quoted and re-checked
  9. Chapter 24 Code of Ordinances, quoted and re-checked
  10. Iowa Code 2026, Chapter 91C — Construction Contractors (Iowa statewide rule), quoted and re-checked
  11. Mills County Building & Zoning (millscountyiowa.gov)
  12. Chapter 27 - Zoning Ordinance, quoted and re-checked
  13. Chapter 27 - Zoning Ordinance, quoted and re-checked
  14. Chapter 4 - Entrance and Driveway, quoted and re-checked
  15. Chapter 24 - Building and Property Maintenance, quoted and re-checked
  16. Building & Zoning, quoted and re-checked
  17. Chapter 24 Code of Ordinances, quoted and re-checked
  18. Chapter 24 - Building and Property Maintenance, quoted and re-checked
  19. Chapter 24 - Building and Property Maintenance, quoted and re-checked
  20. Chapter 24 Code of Ordinances, quoted and re-checked
  21. Mills County Environmental Health Office (millscountyiowa.gov)
  22. Mills County Engineer / Secondary Roads (millscountyiowa.gov)
  23. Chapter 27 - Zoning Ordinance, quoted and re-checked
  24. Chapter 27 - Zoning Ordinance, quoted and re-checked
  25. Chapter 27 - Zoning Ordinance, quoted and re-checked
  26. Iowa Code 2026, Chapter 335 — County Zoning (Iowa statewide rule), quoted and re-checked
  27. Environmental Health, quoted and re-checked
  28. 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
  29. Iowa Code §455B.172, Jurisdiction of department and local boards (Iowa statewide rule), quoted and re-checked
  30. Iowa Code §455B.172, Jurisdiction of department and local boards (Iowa statewide rule), quoted and re-checked
  31. Chapter 27 - Zoning Ordinance, quoted and re-checked
  32. Iowa Code §335.30, Manufactured and modular homes (Iowa statewide rule), quoted and re-checked
  33. Commercial Construction Permit Application, quoted and re-checked
  34. Chapter 27 - Zoning Ordinance, quoted and re-checked
  35. Chapter 27 - Zoning Ordinance, quoted and re-checked
  36. Share of land at 15% slope or less: Bolthole Index county data
  37. Chapter 25 - Subdivision Regulations, quoted and re-checked
  38. Effective property tax rate: Bolthole Index county data
  39. Median property tax bill: Bolthole Index county data
  40. Farmland value per acre (USDA census): Bolthole Index county data
  41. Straight-line distance from the county center to the nearest city of 100,000+ people: 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.

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Compared with neighboring counties

Like all 6 of its neighbors, Mills County has countywide zoning.

RuleMills CountyFremont CountyPottawattamie CountyMontgomery CountyPage CountyCass CountyHarrison County
Building permitRequiredRequiredRequiredLimitedRequiredRequiredRequired
County zoningYesYesYesYesYesYesYes
Septic permitsCounty Env. HealthCounty Board of HealthCounty Public HealthCounty Public HealthCounty Env. Health OfficeCounty Env. Health OfficeCounty Env. Health Dept.

County locator

Mills County in Iowa

56
County map
Mills County highlighted among the Iowa counties · colored by Index score

How Mills County scores

Seclusion43100% ev.
Self-Sufficiency48100% ev.
Admin Boringness48100% ev.
Durability53100% ev.
Property Autonomy51100% ev.
Carry Cost56100% ev.

Evidence strength: 100%. This reports direct-source completeness and fallback use; it is separate from the score and is not a confidence interval. How it works →

$288kTypical home
1.5%Property tax
$8,944Land / acre
34.1"Annual rain
8.5% of yrsSevere drought
8.9 / yr (+7.5)Mid-century 100°F days
18.5 daysMid-century dry spell
1.97" (+6.1%)Mid-century 1-day rain
1.69×Wildfire change factor
100%Forward climate coverage
$2,121Home insurance / yr
2.7% / yrInsurance growth
1.07%Nonrenewal rate
county median (2+ published ZIPs)Insurance basis
15,362People within 30 min
1,874,753People within 2 hr
75,043Radius comparison (15 mi)
33.5People / sq mi
0.4%Federal land
91.9%Land at 15% slope or less
28.5%Soils rated "not limited" for septic (strict USDA rating)
77,215 acWorkable land screen
10.1%Wooded land
37 tonsBiomass / forest ac
51.1°FAvg temp

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Cities and towns in Mills 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.

Emerson · Glenwood · Hastings · Henderson · Malvern · Pacific Junction · Silver City

Answers from the rulebook for Mills County

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

Mills County rules

  • Building permitRequired

    Construction regulated by the Mills County adopted codes.

    • A permit is not valid until prescribed fees are paid.
    • Work begun before obtaining necessary permits may incur an investigative fee and county infraction.
    • Permits have expiration periods and a 90-day commencement rule.
    “Any person who commences any work on a building, structure, electrical, gas, mechanical, plumbing or utility system before obtaining the necessary permits shall be subject to an investigative fee for actual costs incurred by the County that shall be in addition to the required permit fees and/or subject to a Citation of County Infraction.”
  • Owner-builder exemptionConditional

    An owner seeking to act as general contractor for a building permit.

    • A building permit is issued only to a State Registered General Contractor unless the Building Official, in discretion, allows the owner to be the General Contractor.
    • Electrical permits must be obtained from the Iowa Department of Public Safety, State Fire Marshal Division, Electrical Bureau.
    “A building permit shall only be issued to the State Registered General Contractor. At the discretion of the Building Official, the Owner may be allowed to be the General Contractor.”
  • Building code adoptedAdopted (with conditions)

    County building codes administered in unincorporated Mills County.

    • The County lists the 2024 International Building Code, 2024 International Residential Code, 2021 International Mechanical Code, 2018 State Uniform Plumbing Code, 2020 State National Electrical Code, 2018 International Fuel Gas Code, 2018 International Existing Building Code, 2012 State International Energy Conservation Code, and 2018 International Property Maintenance Code.
    • Farmhouses and other farm buildings primarily adapted for agricultural purposes are excluded while so used or under construction for that use.
    • The County code does not apply within incorporated cities except under the stated exceptions.
    “2024 International Building Code 2024 International Residential Code 2021 International Mechanical Code 2018 (State) Uniform Plumbing Code 2020 (State) National Electrical Code 2018 International Fuel Gas Code 2018 International Existing Building Code 2012 (State) International Energy Conservation Code 2018 International Property Maintenance Code”
    One more reviewed finding on this topic
    • Adopted (with conditions) — County-regulated construction and occupancy, including commercial, industrial, multifamily, detached one- and two-family dwellings, and accessory structures.
      “The Building Department has been empowered to enforce the following Codes which shall be hereinafter referred to as "the adopted Codes".”
  • InspectionsRequired

    Residential and commercial construction subject to Chapter 24.

    • Residential inspections must occur at each phase and require a Certificate of Compliance before certificate of occupancy.
    • Commercial phases require inspection by an approved certified agency, architect, or engineer and a written report.
    • Mills County does not conduct electrical inspections; the State may perform them.
    “Each phase of construction must be inspected by licensed and certified agencies, or contractors, or individuals.”
    One more reviewed finding on this topic
    • Required — Residential and commercial construction governed by Chapter 24.
      “Each phase of construction must be inspected by licensed and certified agencies, or contractors, or individuals.”
  • Certificate of occupancyRequired

    New buildings or structures and portions thereof before use or occupancy.

    • A temporary certificate may be issued before all work is complete if the occupied portion is safe.
    • A certificate may be suspended or revoked for error, incorrect information, or code violation.
    “No new building or structure or portion thereof shall be used or occupied until the Building Official has issued a Certificate of Occupancy for the use therefore as provided herein.”
    One more reviewed finding on this topic
    • Limited — Commercial and industrial buildings, and permitted construction for which the Department issues a certificate of occupancy.
      “A certificate of occupancy shall be provided, upon request, for a building or structure constructed in accordance with the provisions of the state building code if the permittee provides verification of the following:”
  • County-wide zoningPresent (with conditions)

    County zoning under Chapter 27 in unincorporated Mills County.

    • The county ordinance applies to unincorporated territory; incorporated cities may administer separate requirements.
    • The zoning ordinance contains district-specific use and development standards.
    “This jurisdiction includes the entire area of Mills County outside of areas within the corporate limits of municipalities or any area in which the County has ceded its zoning jurisdiction to a municipality.”
    One more reviewed finding on this topic
    • Present (with conditions) — County zoning in unincorporated Mills County.
      “A base district designation shall be applied to each area and parcel within the County’s planning jurisdiction.”
  • Local zoningVaries (with conditions)

    Countywide aggregate zoning conclusion: county zoning applies in unincorporated areas, while incorporated municipalities and areas with ceded county jurisdiction may be governed by municipal zoning or other municipal rules.

    • The source does not identify the zoning ordinance of each incorporated municipality.
    • The county Building & Zoning page directs people within city limits to confirm building requirements with city officials.
    “If you live within the city limits please confirm building requirements with city officials.”
  • Zoning districtsPublished (with conditions)

    Mills County zoning districts and their development criteria in unincorporated areas.

    • Chapter 27 Table 4.02 lists district-specific criteria for OS, AG, AR, LH, V, CC, CH, and I zoning districts.
    • Planned Unit Developments may vary density, front-yard setback, building coverage, impervious coverage, and height requirements under Section 27.7.4.
    • Loess Hills Conservation development criteria may be the same as Agriculture/Residential when crop-land history is proven by Farm Service Agency maps.
    “Table 4.02: Development Criteria for Zoning Districts Site Area per Unit OS AG AR LH”
    One more reviewed finding on this topic
    • Published (with conditions) — Published Mills County zoning districts for the county zoning jurisdiction.
      “The following base districts and overlay districts are hereby established.”
  • Minimum lot sizeDistrict specific (with conditions)

    Minimum lot sizes in Mills County zoning districts.

    • Requirements vary by zoning district and development type.
    • For OS, AG, AR, and LH districts, the table lists conventional residential minimum lot sizes of ¼-¼ section, 2 acres, 2 acres, and 3 acres respectively.
    • For conservation residential development, the LH district lists 1 acre.
    • For V, CC, CH, and I districts, the table includes 1 acre without sewer and 10,000 square feet with sewer in V; 2 acres in CH; and ¼-¼ section in I.
    • Planned Unit Developments may vary density and related standards under Section 27.7.4.

    minimum lot size: district-specific (See Table 4.02 and Section 27.7.4 for PUD variation.)

    “Minimum lot size (conventional residential development) ¼-¼ section 2 acres* 2 acres 3 acres”
    One more reviewed finding on this topic
    • Specified — Minimum lot size in Mills County zoning districts under Chapter 27 Table 4.02.
      “Minimum lot size (conventional residential development) ¼-¼ section 2 acres* 2 acres 3 acres Minimum lot size (conservation residential development) NA NA NA 1 acre”
  • SetbacksDistrict specific (with conditions)

    Minimum front, side, and rear yards in Mills County zoning districts.

    • Table 4.02 lists district-specific minimum front, side, and rear yards.
    • For OS, AG, AR, and LH, minimum front yards are 100, 75, 75, and 75 feet; side yards are 10 feet; rear yards are 25 feet.
    • For V, CC, CH, and I, the table lists front yards of NA, 25, 25, and 25 feet; side yards of NA, 10, 10, and 10 feet; rear yards of NA, 50, 50, and 50 feet.
    • Major subdivisions with public water or sewer have a 25-foot minimum front yard in the OS, AG, AR, and LH columns.

    minimum front yard: 25-100 feet (District-specific; see Table 4.02.) · minimum side yard: 10 feet (Where a numeric requirement is listed.) · minimum rear yard: 25-50 feet (District-specific; see Table 4.02.)

    “Minimum front yard 100 feet 75 feet 75 feet 75 feet”
    One more reviewed finding on this topic
    • Specified — Required yards and setbacks in Mills County zoning districts under Chapter 27 Table 4.02.
      “Minimum front yard 100 feet 75 feet 75 feet 75 feet Minimum front yard (major subdivision with public water or sewer) 25 feet 25 feet 25 feet 25 feet Minimum side yard 10 feet 10 feet 10 feet 10 feet Minimum rear yard 25 feet 25 feet 25 feet 25 feet”
  • Lot coverageSpecified

    Maximum building coverage in Mills County zoning districts under Chapter 27 Table 4.02.

    • For OS, AG, AR, and LH districts, maximum building coverage is 1%, 5%, 15%, and 5% respectively.
    • For V, CC, CH, and I districts, the table lists additional district-specific coverage limits.
    • Coverage requirements may be varied within Planned Unit Developments under Section 27.7.4.
    “Maximum building coverage 1% 5% 15% 5% Maximum impervious coverage (excluding structure) 5% 10% 10% 10%”
  • Building heightDistrict specific (with conditions)

    Maximum building height in Mills County zoning districts.

    • For OS, AG, AR, and LH, maximum height is 25, 35, 35, and 35 feet.
    • For V, CC, CH, and I, maximum height is 35, 50, 50, and 50 feet.
    • Industrial/manufacturing equipment, smokestacks, silos, and approved above-ground landfills may reach 200 feet subject to the stated restrictions.
    • Planned Unit Developments may vary height requirements under Section 27.7.4.

    maximum building height: 25-50 feet (District-specific; separate industrial-equipment exception may reach 200 feet.)

    “Maximum height 25 feet 35 feet 35 feet 35 feet”
    One more reviewed finding on this topic
    • Specified — Maximum building height in Mills County zoning districts under Chapter 27 Table 4.02.
      “Maximum height 25 feet 35 feet 35 feet 35 feet”
  • Manufactured homesAllowed (with conditions)

    Manufactured homes in unincorporated Mills County where single-family dwelling units are permitted.

    • Manufactured homes are considered the same as single-family detached dwellings for these regulations.
    • Wheels, axles, transporting lights, and removable towing apparatus must be removed if present.
    • The dwelling must be placed on a permanent foundation approved by the Building Official and Zoning Official.
    • All utility services must be directly connected to the structure.
    • Manufactured homes not meeting those standards may be placed in a manufactured home park or as otherwise permitted by code, subject to the stated dimensional requirements.
    “Dwelling units built in compliance with the above may be placed in any zoning district where single-family dwelling units are permitted when the following additional requirements are met.”
  • Who permits septicCounty

    Septic permitting and inspections in Mills County.

    • The County Environmental Division administers permits and inspections.
    • The County page directs residents to the Iowa Department of Natural Resources for additional information.
    “Residents can obtain permits to construct or repair septic systems through the Environmental Division.”
    One more reviewed finding on this topic
    • County (with conditions) — On-site wastewater permitting and inspection in Mills County.
      “Residents can obtain permits to construct or repair septic systems through the Environmental Division.”
  • Septic permitRequired

    Construction or repair of septic systems in Mills County.

    • Online permits do not apply.
    • Permits are obtained through the County Environmental Division.
    “All septic systems in Mills County require a permit to construct or repair.”
  • Septic inspectionRequired

    Permitted septic construction and repair.

    • Inspection occurs before construction and after construction.
    • The permit includes a certification report.
    • The installed system must remain open for final inspection and the final inspection must be scheduled in advance.
    “The permit fee includes a pre-site inspection and a final inspection with a certification report.”
    One more reviewed finding on this topic
    • Required — Septic systems constructed or repaired in Mills County.
      “Currently, septic systems are inspected in both pre-construction and post-construction phases to verify proper location as well as proper construction.”
  • Well permitRequired

    Construction of private wells in Mills County.

    • The Mills County Board of Health or its agent issues required permits.
    • Fees are established by Board of Health policy.
    • Chapter 15 adopts Iowa Administrative Code requirements by reference.
    “The Board of Health or its agent shall be responsible for issuance of required permits.”
    One more reviewed finding on this topic
    • Required — Construction of new private wells in Mills County.
      “All wells in Mills County require a permit to construct. Starting in 2003 all wells will also be inspected during their construction.”
  • Mandatory utility hookupConditional

    Connections to utilities, energy, fuel, or power for buildings or systems regulated by adopted codes.

    • The applicable permit must exist.
    • The connection cannot be made until inspection by a licensed and certified agency, contractor, or individual.
    • Emergency utility disconnection may be authorized by the Building Official.
    “No person shall make connections from a utility, source of energy, fuel or power to any building or system that is regulated by the adopted Codes for which a permit is required, until inspected by a licensed and certified agency, contractor, or individual.”
  • Agricultural exemptionAvailable (with conditions)

    Division of agricultural land in unincorporated Mills County where the land's use is not changed.

    • The exemption is limited to the Chapter 25 sewer/septic and water requirements.
    • Other zoning, subdivision, building, health, or environmental requirements may still apply.
    “The division of agricultural land in which use is not changed shall be exempt from this Ordinance concerning sewer/septic and water requirements.”
    One more reviewed finding on this topic
    • Conditional — Farmhouses and other farm buildings primarily adapted for agricultural purposes while so used or under construction for that use.
      “A county building code shall not apply to farmhouses or other farm buildings which are primarily adapted for use for agricultural purposes, while so used or under construction for that use.”
  • Subdividing landRegulated (with conditions)

    Property splits, property-line adjustments, subdivisions, and re-subdivisions in unincorporated Mills County.

    • Agricultural land divisions in which use is not changed are exempt from the ordinance's sewer/septic and water requirements.
    • A 28E agreement with a municipality may affect review procedures.
    • Major subdivisions require sketch plat, preliminary plat, final construction plans, and final plat applications; minor subdivisions require sketch plat, preliminary plat, and final plat applications; property splits and property-line adjustments require sketch plat applications.
    • Required fees are obtained from the County Auditor's office.
    “This Subdivision Ordinance is adopted to establish rules, regulations and minimum standards for property splits, property line adjustments and for the design, development and improvement of all new subdivisions and re-subdivisions within the County.”
  • Driveway accessRequired

    Entrances and driveways connected to Mills County public roads under County jurisdiction.

    • A county permit is required for each entrance.
    • Existing entrances built before the ordinance’s effective date may continue in use and are treated as having valid permits.
    • A changed or modified driveway, or one with expected increased traffic, must comply with current standards.
    • Applications are filed with the Mills County Secondary Roads Department and require the applicable fee.
    • The Engineer reviews location requirements and may establish culvert diameter and length.
    “The County regulates the placement of entrances along the public roads under its jurisdiction and each entrance must have a county permit.”
    One more reviewed finding on this topic
    • Limited — Driveway entrances and front yards associated with property divisions and subdivisions in unincorporated Mills County.
      “Front yards and driveway entrances shall not be relocated without prior approval of the County Board and the Mills County E911 Board.”
  • Permit feesVariable (with conditions)

    Building, plumbing, mechanical, fuel-gas, and related county permits.

    • Fees are established by resolution or the current county schedule of fees.
    • A permit is not valid until prescribed fees are paid.
    • Electrical permit fees are handled by the Iowa Department of Public Safety rather than collected by Mills County.
    “There shall be permit fees as found in the Schedule of Fees for the Building Code as set forth by resolution. There shall be a permit issuance fee for applications.”
  • Permit processPublished (with conditions)

    County building-permit process for unincorporated Mills County.

    • The Building Official receives applications, reviews construction documents, and issues permits.
    • Construction documents must be submitted in writing when a permit is issued, with one set retained by the Building Official.
    • The County provides building permit and commercial construction permit applications.
    • Incomplete commercial plans will not be accepted.
    “To obtain a permit, the applicant shall first file an application therefore in writing on a form furnished by the Building Department for that purpose.”
    One more reviewed finding on this topic
    • Partial — County building and development permit processes in unincorporated Mills County.
      “Building Forms Building Permit Application Commercial Construction Permit Application”

Iowa rules that apply here

  • Minimum dwelling sizeDistrict specific (with conditions)

    Minimum dwelling-size standards imposed by county zoning regulations on manufactured homes in Iowa.

    • County zoning under chapter 335 is optional and applies only where the county board of supervisors has adopted it.
    • The local standard must be the same standard applicable to a site-built single-family dwelling on the same lot.
    • The cited provision does not supply a statewide numeric minimum square-footage value.
    “However, a zoning ordinance or regulation shall require that a manufactured home be located and installed according to the same standards, including but not limited to a permanent foundation system, set-back, and minimum square footage, which would apply to a site-built, single family dwelling on the same lot, and shall require that the home is assessed and taxed as a site-built dwelling.”
  • Accessory dwellingsAllowed (with conditions)

    City regulation of accessory dwelling units statewide in Iowa, within a zoning district where a single-family residence is an allowed principal use

    • At least one accessory dwelling unit must be allowed on the same lot as a single-family residence.
    • The accessory dwelling unit must comply with applicable building regulations under chapter 103A.
    • The unit may not exceed 1,000 square feet or 50 percent of the size of the single-family residence, whichever is larger; unfinished basements are excluded from the size calculation.
    • Historic-building-code restrictions, deed restrictions, and common-interest-community rules may limit or prohibit construction or use.
    • A manufactured or mobile home used as the accessory dwelling unit must be converted to real property by placement on a permanent foundation and assessed for real-estate taxes under section 435.26.
    • A historic-preservation area may regulate the unit to the extent the city or commission determines it incongruous and records its reasons.
    • Effective July 1, 2026.

    maximum accessory dwelling unit size: 1,000 square feet or 50% of the single-family residence, whichever is larger (unfinished basements excluded from the size calculation)

    “A city shall allow a minimum of one accessory dwelling unit on the same lot as a single family residence within a zoning district where a single family residence is an allowed principal use, in accordance with the following conditions:”
    One more reviewed finding on this topic
    • Allowed (with conditions) — County regulation of accessory dwelling units statewide in Iowa, within a zoning district where a single-family residence is an allowed principal use
      “A county shall allow a minimum of one accessory dwelling unit on the same lot as a single family residence within a zoning district where a single family residence is an allowed principal use, in accordance with the following conditions:”
  • county zoning authorityGeneral

    Iowa counties may adopt zoning ordinances for land and structures within the county but outside the corporate limits of any city.

    • Chapter 335 applies to any Iowa county at the option of its board of supervisors.
    • The zoning power is subject to Iowa Code section 335.2: ordinances generally do not apply to agricultural land, farm houses, farm barns, farm outbuildings, or other structures primarily adapted for agricultural purposes while so used, except that ordinances may apply to structures, buildings, dams, obstructions, deposits, or excavations in or on river or stream floodplains.
    • A county may not require an application, approval, or fee for an ordinance to be deemed inapplicable to qualifying agricultural land or structures.
    • A county may not regulate, restrict, or prohibit the location of permanent buildings or temporary structures used for consumer-fireworks sales pursuant to section 10A.519 in locations zoned commercial or industrial.
    • The board of supervisors may divide the county into zoning districts, and regulations may differ among districts.
    • Regulations and restrictions require public-hearing and notice procedures under sections 335.6 and 331.305; district boundaries must identify the affected township and section and, if possible, streets or roads.
    • Energy-conservation and solar-access objectives do not require zoning in a county that did not have zoning before July 1, 1981.
    “applicable to any county [...] at the option of the board of supervisors [...] outside of the corporate limits of any city.”
  • county building authorityGeneral

    Iowa counties may adopt, administer, and enforce county building codes and may administer and enforce the state building code for buildings, including residential construction, in county jurisdiction outside incorporated municipalities, subject to statutory limitations.

    • A county building code may not apply within the incorporated area of a city except at the city's option.
    • A county building code may not apply within a city's two-mile limit under Iowa Code §414.23 to the extent the city has adopted a building code within that two-mile limit.
    • A county building code may not apply to farm houses or other farm buildings primarily adapted for agricultural purposes while so used or under construction for that use.
    • Administration and enforcement are conducted as prescribed by local law or ordinance.
    • The state building code applies in a governmental subdivision only after the governing body adopts an ordinance accepting it and files a certified copy with the commissioner; the ordinance fixes the effective date, which must be no more than six months after adoption.
    • A local building department may prohibit commencement of construction until a permit is issued after showing compliance with applicable state building-code provisions.
    • Thermal-efficiency energy-conservation standards apply to construction containing heated or cooled enclosed space, but the commissioner must provide appropriate exceptions where applying an energy-conservation requirement would be impractical.
    “The power to adopt, administer, and enforce the state building code shall be exercised in accordance with chapter 103A. The power to adopt by ordinance, administer, and enforce a county building code, is subject to the following restrictions: a. A county building code shall not apply within the incorporated area of a city except at the option of the city, and shall not apply within a city’s two-mile limit referred to in section 414.23, to the extent that the city has adopted a building code within the two-mile limit. b. A county building code shall not apply to farm houses or other farm buildings which are primarily adapted for use for agricultural purposes, while so used or under construction for that use.”

Still unanswered

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

  • Living in an RV — Long-term or residential recreational-vehicle occupancy on private land in unincorporated Mills County.
  • Camping on your land — Temporary camping on private land in unincorporated Mills County.
  • Tiny homes — Tiny-home occupancy in unincorporated Mills County.
  • Off-grid sanitation — Off-grid sanitation systems in Mills County.
  • Building in a floodplain — Development in Mills County floodplain areas.
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.

Living off-grid in Mills County, Iowa

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

Mills County scores 56/100 on the Bolthole Index, a solid county profile.

Do you need a building permit in Mills County, Iowa?

Mills County generally requires a residential building permit, and it enforces county zoning. Onsite septic is permitted by Mills County Environmental Health / County Board of Health. 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 Mills County, Iowa?

Land in Mills County runs about $8,944 per acre, based on the latest county data.

What is the water situation in Mills County?

Mills County gets about 34.1" of rain a year, with severe drought in roughly 8.5% of years.

How remote is Mills County?

A representative private-land location has about 15,362 people within a 30-minute drive and 1,874,753 within two hours. The road-network catchments count population across county lines and clusters of smaller cities; straight-line radius values remain available as a comparison.

How Mills compares in Iowa

Compare side-by-side →See all 99 Iowa counties ranked →