Bolthole Index

Mills County, Texas

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

70Index Score / 100
#38 of 254 in Texas

Unincorporated Mills County, Texas has no county zoning, and we could not confirm a general county building permit for a home.12 Septic permits, county-road driveway permits and floodplain development permits in mapped flood areas do apply, all through the County Judge's office, and a lot created by a subdivision needs a recorded final plat before construction.34

At a glance

Building permit
No general county permit confirmed; subdivision lots need a recorded plat first; floodplain permit in flood zones245
County zoning
None; Texas reserves zoning power to specific counties and Mills isn't one16
Septic (OSSF) permit
Required for every OSSF regardless of acreage, through the County Judge's office; $335 application/inspection fee as of 9/1/202578
RV, tiny home & manufactured home
Unrestricted by county rule; the county has no zoning authority to limit them9
Setbacks & minimum lot size
None set by the county9
Owner-builder
Texas has no state residential-builder license; a homeowner may install their own OSSF only if Mills County's requirements allow it and conditions are met1011
County-road driveway access
$50 permit from the County Judge's office required before work starts12

Who to call

Also useful

Mills County Judge's Office

General county administration; the intake point for OSSF (septic) permit applications, county-road driveway/access permits, and floodplain development permits, and the Floodplain Administrator for Mills County

(325) 648-2222

Mills County Courthouse, 1011 4th Street, Goldthwaite, TX 76844

Online permits →

Contact details are copied from each office’s official page and were checked against it on October 10, 2026.

Off-grid gear

Going off-grid in Mills 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 Mills County, Texas?

We could not confirm a general county building permit for a house in unincorporated Mills County, Texas. The county's published processes cover floodplain development, septic installation, county-road driveway access and subdivision platting, and the reviewed sources established no general residential building-permit process.2 Texas law limits county building-permit authority: fire-code permits for specified buildings are open only to counties with a population over 250,000 or adjacent to one, and residential-code standards need a commissioners court order.13 No official record shows Mills County has adopted either program, so treat this as unconfirmed rather than assume state code inspections apply here.

Two exceptions matter. On a lot created by a subdivision outside a city, the final plat must be approved and recorded before construction begins.4 In mapped flood hazard areas, a Floodplain Development Permit is required.5 Industrialized housing and manufactured homes are a separate track regulated by the state rather than the county.14

Who handles septic, driveway and floodplain permits in Mills County, since there's no building department?

Mills County has no building or zoning department, so most land-use paperwork routes through one place: the County Judge's office at the Mills County Courthouse in Goldthwaite3. Septic (OSSF) permit applications, county-road driveway/access permit applications, and floodplain development permit applications are all submitted there21215. The County Judge also serves as Mills County's Floodplain Administrator, reviewing, approving or denying floodplain development permits15. For anything not covered here, call the County Judge's office first.

Does Mills County have zoning?

No. Texas grants county zoning power only to specific, legislatively named areas, and Mills County isn't one of them, so the county has no zoning ordinance and no zoning districts16. Because the county has no zoning authority, it sets no minimum dwelling size, no minimum lot size, no setbacks, no lot-coverage limit and no building-height limit anywhere in unincorporated Mills County9. That's a legal consequence of state law, not a gap in local records: it applies countywide unless you're inside the City of Goldthwaite or another incorporated town, which can and do set their own rules.

How do septic (OSSF) permits work in Mills County?

An on-site sewage facility (septic) permit is required before you build, and Mills County itself is the local permitting authority, acting as TCEQ's authorized agent.16 Mills County's order requires a permit for all on-site sewage facilities in unincorporated areas regardless of acreage.7 Applications go to the County Judge's office with a nonrefundable $335 application/inspection fee, current as of September 1, 2025.83 Once installed, contact the county's on-site sewage inspector at least five working days before you want the inspection.8

The state's 10-acre exemption exists, but Mills County's acreage-blind order means you should not rely on it without asking the County Judge's office first.177 An approved composting toilet still needs an approved OSSF for all other wastewater.18 Soils are tight here: only about 5.9% of Mills County's land has soils without severe limits for a conventional drain field, so plan for an engineered or alternative system on most parcels.19

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

Yes, county rules don't restrict it: because Mills County has no zoning authority, there is no county rule limiting RV occupancy, tiny-home occupancy or manufactured-home placement on private land in unincorporated Mills County9. Accessory dwellings are likewise unrestricted by county rule9. That freedom is about zoning only; it doesn't remove your septic, driveway or floodplain-permit obligations, which apply regardless of what kind of dwelling you put on the land157. If you're inside Goldthwaite or another incorporated city, that city's own rules take over instead.

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

  1. Confirm the parcel is unincorporated, outside Goldthwaite or any other city with its own permitting rules1.
  2. Get a site evaluation for your OSSF (septic) early, since most of the county's soil isn't suited to a conventional drain field, and apply through the County Judge's office with the $335 fee38.
  3. If the lot was created by a subdivision, confirm its final plat was approved and recorded before you start construction4.
  4. If your driveway will connect to a county road, submit a driveway/access permit and the $50 fee to the County Judge's office before starting work12.
  5. If your parcel is in a mapped flood hazard area, get a Floodplain Development Permit from the County Judge's office before you build15.
  6. Because we could not confirm a general county building permit, keep your septic permit, driveway permit and any floodplain paperwork on file in case a lender or insurer asks2.

What to check before you buy land in Mills County

Soils and septic: under 6% of Mills County land is free of severe limitations for a conventional septic field, so budget for a site evaluation and possibly an engineered system before you commit to a parcel19. Terrain: almost 95% of the county sits at 15% slope or less, which is gentle building ground, though the land is mostly open rather than wooded2021. Flood: a Floodplain Development Permit is required for construction in Mills County's mapped flood hazard areas, so check flood status with the County Judge's office before you buy15. Access: any new driveway onto a county road needs a $50 permit and 48-hour notice to the County Commissioner before work starts, and a driveway onto a state highway needs a separate TxDOT permit1222. Taxes: the effective property tax rate is about 0.9%, with a median annual bill near $1,7622324.

Watch-outs

  • Mills County's septic order says permits are required for all on-site sewage facilities regardless of acreage, so confirm with the County Judge's office before relying on the state's 10-acre exemption.73
  • No official record shows Mills County has adopted Texas's optional residential building-code program under Local Government Code Chapter 23313; don't assume state building-code inspections apply here, and confirm with the County Judge's office before you build3.
  • Short-term rental rules for Mills County were not found on an official county page; check with the County Judge's office before you plan to rent out a property3.

Sources

  1. Texas Local Government Code Chapter 231 (County Zoning Authority) (2026 county census)
  2. Flood Damage Prevention Court Order, quoted and re-checked
  3. Mills County Judge's Office (millscountytx.gov)
  4. Mills County Subdivision Regulations and County Road Standards, quoted and re-checked
  5. Mills County Flood Damage Prevention Order, quoted and re-checked
  6. Local Government Code Chapter 231, County Zoning Authority (Texas statewide rule), quoted and re-checked
  7. Septic System Permits | Mills County, TX, quoted and re-checked
  8. Septic System Permits, quoted and re-checked
  9. Texas law on county zoning and building authority
  10. TCEQ - OSSF Information for Homeowners (2026 county census)
  11. Getting a Permit for an OSSF - Such as a Septic System, quoted and re-checked
  12. Mills County Road Access Policy, quoted and re-checked
  13. Local Government Code Chapter 233, County Regulation of Housing and Other Structures (Texas statewide rule), quoted and re-checked
  14. tdlr.texas.gov (Texas statewide rule), quoted and re-checked
  15. Flood Damage Prevention Court Order, quoted and re-checked
  16. TCEQ - Getting a Permit for an OSSF (Septic System) (2026 county census)
  17. Getting a Permit for an OSSF - Such as a Septic System (Texas statewide rule), quoted and re-checked
  18. Approved Product - Composting Toilet, quoted and re-checked
  19. 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
  20. Share of land at 15% slope or less: Bolthole Index county data
  21. Wooded share of land: Bolthole Index county data
  22. Section 4: Driveway Permits, Design, and Materials (Texas statewide rule), quoted and re-checked
  23. Effective property tax rate: Bolthole Index county data
  24. Median property tax bill: Bolthole Index county data

Written October 10, 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

Unlike 5 of its 6 neighbors, Mills County requires a building permit only in limited cases.

RuleMills CountySan Saba CountyLampasas CountyComanche CountyBrown CountyHamilton CountyMcCulloch County
Building permitLimitedLimitedNot requiredNot requiredNot requiredNot requiredNot required
County zoningNoNoNoNoNoNoNo
Septic permitsCounty OSSF programCounty On-Site Sewage Facility officeCounty OSSF ProgramComanche CountyCounty OSSF programHamilton CountyMcCulloch County

County locator

Mills County in Texas

70
County map
Mills County highlighted among the Texas counties · colored by Index score

How Mills County scores

Seclusion77100% ev.
Self-Sufficiency3996% ev.
Admin Boringness91100% ev.
Durability44100% ev.
Property Autonomy71100% ev.
Carry Cost7296% ev.

Evidence strength: 99%. This reports direct-source completeness and fallback use; it is separate from the score and is not a confidence interval. How it works →

$396kTypical home
0.9%Property tax
$3,731Land / acre
30.8"Annual rain
29.7% of yrsSevere drought
33.5 / yr (+22.3)Mid-century 100°F days
28.6 daysMid-century dry spell
1.86" (+5.1%)Mid-century 1-day rain
1.38×Wildfire change factor
100%Forward climate coverage
$2,137Home insurance / yr
0.1% / yrInsurance growth
0%Nonrenewal rate
single ZIP shrunk to state medianInsurance basis
1,319,168People within 2 hr
4,844Radius comparison (15 mi)
6.1People / sq mi
0%Federal land
94.9%Land at 15% slope or less
5.9%Soils rated "not limited" for septic (strict USDA rating)
27,293 acWorkable land screen
16.8%Wooded land
9.9 tonsBiomass / forest ac
65.6°FAvg temp

Scout Mills 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 Mills 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 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.

Goldthwaite · Town of Mullin

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 permitLimited

    Construction activities on proposed lots created by a subdivision outside incorporated municipalities in Mills County.

    • The final plat must be approved and recorded before construction activities commence on the proposed lots.
    • The regulation concerns subdivision plat approval and does not state that a general county building permit is required for every residential construction project.
    • Municipal and extraterritorial-jurisdiction requirements may also apply where applicable.
    • On-site sewage facilities are separately subject to Mills County OSSF permitting requirements.
    “The Final Plat shall be approved and recorded prior to the sale of any Lots in a Subdivision, or commencement of any construction activities on the proposed Lots created by the plat.”
    One more reviewed finding on this topic
    • Limited — Residential structures and other development in areas of special flood hazard within Mills County's jurisdiction.
      “The order shall apply to all areas of special flood hazard with the jurisdiction of Mills County. [...] A Floodplain Development Permit shall be required to ensure conformance with the provisions of this order.”
  • Zoning districts · by state lawNo county rule

    Unincorporated Mills County: no county rule sets this, because Mills County has adopted no county zoning ordinance (Texas law lets some counties zone, but this one has not). The county legal census found no county zoning ordinance, citing statutes.capitol.texas.gov.

    • Septic, floodplain, subdivision and health rules still apply; cities and towns set their own rules inside their limits.
    • Chapter 231 does not grant a general statewide county zoning power; authority is provided through geographically or subject-matter limited subchapters.
    • For Padre Island, the authority applies in Cameron or Willacy County outside a municipality and within two miles of a publicly owned park or recreational development, or within two miles of a beach, wharf, or bathhouse used by at least 500 persons annually.
    “This subchapter applies to the areas of Padre Island located in Cameron or Willacy County and located: (1) outside a municipality but within two miles of a publicly owned park or recreational development; or (2) within two miles of a beach, wharf, or bathhouse used by at least 500 persons annually.”
  • Minimum dwelling size · by state lawNo county rule

    Unincorporated Mills County: no county rule sets this, because Mills County has adopted no county zoning ordinance (Texas law lets some counties zone, but this one has not). The county legal census found no county zoning ordinance, citing statutes.capitol.texas.gov.

    • Septic, floodplain, subdivision and health rules still apply; cities and towns set their own rules inside their limits.
    • Chapter 231 does not grant a general statewide county zoning power; authority is provided through geographically or subject-matter limited subchapters.
    • For Padre Island, the authority applies in Cameron or Willacy County outside a municipality and within two miles of a publicly owned park or recreational development, or within two miles of a beach, wharf, or bathhouse used by at least 500 persons annually.
    “This subchapter applies to the areas of Padre Island located in Cameron or Willacy County and located: (1) outside a municipality but within two miles of a publicly owned park or recreational development; or (2) within two miles of a beach, wharf, or bathhouse used by at least 500 persons annually.”
  • Minimum lot size · by state lawNo county rule

    Unincorporated Mills County: no county rule sets this, because Mills County has adopted no county zoning ordinance (Texas law lets some counties zone, but this one has not). The county legal census found no county zoning ordinance, citing statutes.capitol.texas.gov.

    • Septic, floodplain, subdivision and health rules still apply; cities and towns set their own rules inside their limits.
    • Chapter 231 does not grant a general statewide county zoning power; authority is provided through geographically or subject-matter limited subchapters.
    • For Padre Island, the authority applies in Cameron or Willacy County outside a municipality and within two miles of a publicly owned park or recreational development, or within two miles of a beach, wharf, or bathhouse used by at least 500 persons annually.
    “This subchapter applies to the areas of Padre Island located in Cameron or Willacy County and located: (1) outside a municipality but within two miles of a publicly owned park or recreational development; or (2) within two miles of a beach, wharf, or bathhouse used by at least 500 persons annually.”
  • Setbacks · by state lawNo county rule

    Unincorporated Mills County: no county rule sets this, because Mills County has adopted no county zoning ordinance (Texas law lets some counties zone, but this one has not). The county legal census found no county zoning ordinance, citing statutes.capitol.texas.gov.

    • Septic, floodplain, subdivision and health rules still apply; cities and towns set their own rules inside their limits.
    • Chapter 231 does not grant a general statewide county zoning power; authority is provided through geographically or subject-matter limited subchapters.
    • For Padre Island, the authority applies in Cameron or Willacy County outside a municipality and within two miles of a publicly owned park or recreational development, or within two miles of a beach, wharf, or bathhouse used by at least 500 persons annually.
    “This subchapter applies to the areas of Padre Island located in Cameron or Willacy County and located: (1) outside a municipality but within two miles of a publicly owned park or recreational development; or (2) within two miles of a beach, wharf, or bathhouse used by at least 500 persons annually.”
  • Lot coverage · by state lawNo county rule

    Unincorporated Mills County: no county rule sets this, because Mills County has adopted no county zoning ordinance (Texas law lets some counties zone, but this one has not). The county legal census found no county zoning ordinance, citing statutes.capitol.texas.gov.

    • Septic, floodplain, subdivision and health rules still apply; cities and towns set their own rules inside their limits.
    • Chapter 231 does not grant a general statewide county zoning power; authority is provided through geographically or subject-matter limited subchapters.
    • For Padre Island, the authority applies in Cameron or Willacy County outside a municipality and within two miles of a publicly owned park or recreational development, or within two miles of a beach, wharf, or bathhouse used by at least 500 persons annually.
    “This subchapter applies to the areas of Padre Island located in Cameron or Willacy County and located: (1) outside a municipality but within two miles of a publicly owned park or recreational development; or (2) within two miles of a beach, wharf, or bathhouse used by at least 500 persons annually.”
  • Building height · by state lawNo county rule

    Unincorporated Mills County: no county rule sets this, because Mills County has adopted no county zoning ordinance (Texas law lets some counties zone, but this one has not). The county legal census found no county zoning ordinance, citing statutes.capitol.texas.gov.

    • Septic, floodplain, subdivision and health rules still apply; cities and towns set their own rules inside their limits.
    • Chapter 231 does not grant a general statewide county zoning power; authority is provided through geographically or subject-matter limited subchapters.
    • For Padre Island, the authority applies in Cameron or Willacy County outside a municipality and within two miles of a publicly owned park or recreational development, or within two miles of a beach, wharf, or bathhouse used by at least 500 persons annually.
    “This subchapter applies to the areas of Padre Island located in Cameron or Willacy County and located: (1) outside a municipality but within two miles of a publicly owned park or recreational development; or (2) within two miles of a beach, wharf, or bathhouse used by at least 500 persons annually.”
  • Living in an RV · by state lawNo county rule

    Unincorporated Mills County: no county rule sets this, because Mills County has adopted no county zoning ordinance (Texas law lets some counties zone, but this one has not). The county legal census found no county zoning ordinance, citing statutes.capitol.texas.gov.

    • Septic, floodplain, subdivision and health rules still apply; cities and towns set their own rules inside their limits.
    • Chapter 231 does not grant a general statewide county zoning power; authority is provided through geographically or subject-matter limited subchapters.
    • For Padre Island, the authority applies in Cameron or Willacy County outside a municipality and within two miles of a publicly owned park or recreational development, or within two miles of a beach, wharf, or bathhouse used by at least 500 persons annually.
    “This subchapter applies to the areas of Padre Island located in Cameron or Willacy County and located: (1) outside a municipality but within two miles of a publicly owned park or recreational development; or (2) within two miles of a beach, wharf, or bathhouse used by at least 500 persons annually.”
  • Camping on your land · by state lawNo county rule

    Unincorporated Mills County: no county rule sets this, because Mills County has adopted no county zoning ordinance (Texas law lets some counties zone, but this one has not). The county legal census found no county zoning ordinance, citing statutes.capitol.texas.gov.

    • Septic, floodplain, subdivision and health rules still apply; cities and towns set their own rules inside their limits.
    • Chapter 231 does not grant a general statewide county zoning power; authority is provided through geographically or subject-matter limited subchapters.
    • For Padre Island, the authority applies in Cameron or Willacy County outside a municipality and within two miles of a publicly owned park or recreational development, or within two miles of a beach, wharf, or bathhouse used by at least 500 persons annually.
    “This subchapter applies to the areas of Padre Island located in Cameron or Willacy County and located: (1) outside a municipality but within two miles of a publicly owned park or recreational development; or (2) within two miles of a beach, wharf, or bathhouse used by at least 500 persons annually.”
  • Tiny homes · by state lawNo county rule

    Unincorporated Mills County: no county rule sets this, because Mills County has adopted no county zoning ordinance (Texas law lets some counties zone, but this one has not). The county legal census found no county zoning ordinance, citing statutes.capitol.texas.gov.

    • Septic, floodplain, subdivision and health rules still apply; cities and towns set their own rules inside their limits.
    • Chapter 231 does not grant a general statewide county zoning power; authority is provided through geographically or subject-matter limited subchapters.
    • For Padre Island, the authority applies in Cameron or Willacy County outside a municipality and within two miles of a publicly owned park or recreational development, or within two miles of a beach, wharf, or bathhouse used by at least 500 persons annually.
    “This subchapter applies to the areas of Padre Island located in Cameron or Willacy County and located: (1) outside a municipality but within two miles of a publicly owned park or recreational development; or (2) within two miles of a beach, wharf, or bathhouse used by at least 500 persons annually.”
  • Manufactured homes · by state lawNo county rule

    Unincorporated Mills County: no county rule sets this, because Mills County has adopted no county zoning ordinance (Texas law lets some counties zone, but this one has not). The county legal census found no county zoning ordinance, citing statutes.capitol.texas.gov.

    • Septic, floodplain, subdivision and health rules still apply; cities and towns set their own rules inside their limits.
    • Chapter 231 does not grant a general statewide county zoning power; authority is provided through geographically or subject-matter limited subchapters.
    • For Padre Island, the authority applies in Cameron or Willacy County outside a municipality and within two miles of a publicly owned park or recreational development, or within two miles of a beach, wharf, or bathhouse used by at least 500 persons annually.
    “This subchapter applies to the areas of Padre Island located in Cameron or Willacy County and located: (1) outside a municipality but within two miles of a publicly owned park or recreational development; or (2) within two miles of a beach, wharf, or bathhouse used by at least 500 persons annually.”
  • Accessory dwellings · by state lawNo county rule

    Unincorporated Mills County: no county rule sets this, because Mills County has adopted no county zoning ordinance (Texas law lets some counties zone, but this one has not). The county legal census found no county zoning ordinance, citing statutes.capitol.texas.gov.

    • Septic, floodplain, subdivision and health rules still apply; cities and towns set their own rules inside their limits.
    • Chapter 231 does not grant a general statewide county zoning power; authority is provided through geographically or subject-matter limited subchapters.
    • For Padre Island, the authority applies in Cameron or Willacy County outside a municipality and within two miles of a publicly owned park or recreational development, or within two miles of a beach, wharf, or bathhouse used by at least 500 persons annually.
    “This subchapter applies to the areas of Padre Island located in Cameron or Willacy County and located: (1) outside a municipality but within two miles of a publicly owned park or recreational development; or (2) within two miles of a beach, wharf, or bathhouse used by at least 500 persons annually.”
  • Septic permitRequired

    On-site sewage facilities in the unincorporated areas of Mills County, Texas

    • The county rule excludes areas regulated under an existing rule and areas within incorporated cities.
    • The application packet must be completed completely; "See Attached" will not be accepted.
    • Applications must be submitted to the County Judge's office with the $335.00 application/inspection fee.
    • The applicant must contact the Mills County On-Site Sewage Inspector at least five working days before the desired inspection date.
    • The inspector's business hours are Monday through Friday, 8:00 am to 5:00 pm.
    • No refunds of fees are granted.
    • For aerobic-treatment systems, maintenance must be conducted by a TCEQ-registered maintenance company/provider.
    • The county order also requires a $10 fee for each OSSF permit payable to the On-Site Wastewater Treatment Research Council.
    • The county order states it takes effect after approval as required by law and approval by TCEQ; the order is marked REV 08/09 and was passed and approved in 2009.

    application/inspection fee: 335 USD (As of 9/1/2025) · advance inspector contact: >= 5 working days (Before desired inspection date) · research council fee: 10 USD (For each OSSF permit)

    “AS OF 7/27/2009 PERMITS ARE REQUIRED FOR ALL ON-SITE SEWAGE FACILITIES REGARDLESS OF ACREAGE”
  • Septic inspectionRequired

    Mills County OSSF applications and installations.

    • The applicant must contact the Mills County on-site sewage inspector at least five working days before the desired inspection date.
    • The county application/inspection fee is $335.00 as of 9/1/2025.
    • Applications are submitted to the County Judge's office and fees are nonrefundable.

    advance notice: >= 5 working days (Before the desired inspection date) · application/inspection fee: 335 USD (As of 9/1/2025)

    “at least five (5) working days prior to desired inspection date.”
  • Driveway accessLimited

    New or revised private, public, and commercial entrances onto Mills County roads, and subdivision entrances subject to county subdivision regulations.

    • The application is for securing or changing access to the owner's property, not for parking or servicing vehicles on rights of way.
    • The application and fee must be submitted to the County Judge's office.
    • No right-of-way construction may begin before a fully executed permit and 48-hour notice to the County Commissioner.
    • Drainage impacts must be coordinated with and approved by the County Commissioner.
    • For subdivisions, entrances onto public roads are limited to one per lot and driveway culverts are required for all entrances.

    access driveway permit fee: 50 USD · driveway angle from County Road axis: 75 to 90 degrees degrees · minimum culvert spacing: >= 125 feet (The policy states culverts shall be no less than 125 feet from another culvert.)

    “No construction work on the driveway or entrance shall be undertaken on the right of way until a fully executed driveway permit has been received”
  • Building in a floodplainRequired

    Development in areas subject to Mills County's floodplain management order, including construction, substantial improvements, placement of manufactured homes, and subdivision proposals in flood hazard areas.

    • A Floodplain Development Permit is required to ensure conformance with the order.
    • The Floodplain Administrator reviews, approves, or denies development-permit applications.
    • Applications may require scaled plans, elevations, floodproofing information for nonresidential structures, professional certification, and descriptions of watercourse or drainage alterations.
    • New construction and substantial improvements in areas of special flood hazards must satisfy the order's anchoring, flood-damage-resistant materials, utilities, sewage-system, and elevation requirements.
    • Variances are subject to the order's appeal-board procedures and stated exceptions, including certain historic structures, small lots, and functionally dependent uses; variances may not be issued within a designated floodway if the variance would increase flood levels.
    “A Floodplain Development Permit shall be required to ensure conformance with the provisions of this order.”
  • Permit feesVariable (with conditions)

    Mills County subdivision, on-site sewage facility, and county-road driveway-access permits.

    • The subdivision fee schedule states that it is effective January 1, 2022.
    • The septic page states that the application/inspection fee is $335.00 as of September 1, 2025.
    • The county-road access policy was amended November 13, 2023 and requires a $50 permit fee; a preferred county-installed culvert may require an additional $1,500 fee, with possible higher charges for oversized entrances or unusual terrain.

    OSSF application/inspection fee: 335 USD (As of 2025-09-01) · Preliminary Plat fee: $300 + $100 per lot; $1,000 minimum USD (Effective 2022-01-01) · Final Plat fee: $500 + $50 per lot; $1,000 minimum USD (Effective 2022-01-01) · County-road driveway-access permit fee: 50 USD

    “Platting Services Effective January 1, 2022 Preliminary Plat $300 + $100 per lot ($1,000 Minimum Fee) Final Plat $500 + $50 per lot ($1,000 Minimum Fee)”
  • Permit processPartial

    Published Mills County processes for floodplain development, OSSF installation, county-road driveway access, and subdivision platting; no general countywide residential building-permit process was established by the reviewed sources.

    • Floodplain permits are administered by the Mills County Judge as Floodplain Administrator.
    • OSSF applications are submitted to the County Judge's office and require inspection coordination at least five working days before the desired inspection date.
    • County-road driveway work on the right of way may not begin until a fully executed permit is received and 48-hour notice is given to the County Commissioner.
    • Subdivision applications have separate preliminary and final plat procedures and fee requirements.
    “Applications are to be turned into the County Judge's office and must be accompanied by $335.00 application/inspection fee.”
  • County-wide zoningAbsent

    Texas counties generally have no zoning authority in unincorporated areas; Chapter 231 grants zoning power only to specific legislatively designated counties (not Mills County).

    Texas Local Government Code Chapter 231 (County Zoning Authority) ↗Scouted from the county site, not yet independently re-checked

Texas rules that apply here

  • Owner-builder exemptionConditional

    A homeowner installing an on-site sewage facility serving the homeowner's single-family residence in Texas, including Mills County.

    • Whether the homeowner may install the OSSF depends on whether the permitting authority allows it under local requirements.
    • The homeowner must have the knowledge, skills, and equipment to perform the work.
    • The OSSF must serve a single-family dwelling that the homeowner owns.
    • The homeowner must own the property.
    • No part of the property may be developed for sale or lease.
    • All permitting, construction, and maintenance requirements of the permitting authority must be met.
    • Some systems may not be purchased by a homeowner because they must be installed by a factory representative.
    • If another person assists with installation, that person must generally be a licensed installer, subject to the stated exceptions for licensed electricians and persons delivering and setting treatment or pump tanks.
    “This depends on whether the permitting authority allows this in their local requirements. Otherwise yes, provided you have the knowledge, skills, and equipment to do so AND: the OSSF is for a single family dwelling that you own, you also own the property, no part of the property will be developed for sale or lease, all permitting, construction, and maintenance requirements of the permitting authority are met.”
    2 more reviewed findings on this topic
    • Conditional — An owner performing electrical, plumbing, or air-conditioning and refrigeration work on the owner's own residence or homestead in Texas.
      “A person who perform electrical work on a dwelling that they own and reside in is not required by the state to be licensed as electricians.”
    • Conditional — Electrical work on a dwelling owned and occupied by the property owner in Texas.
      “A person who perform electrical work on a dwelling that they own and reside in is not required by the state to be licensed”
  • Building code adoptedPartial

    Industrialized housing and buildings, modules, and modular components governed by the Texas Industrialized Housing and Buildings program.

    • The mandatory state code adoption applies to industrialized housing and buildings, modules, and modular components, not all construction statewide.
    • The effective date is July 1, 2024.
    • The International Existing Building Code applies to alterations of portable industrialized buildings.
    • Manufacturers already certified for Texas must have design-package documents reviewed and approved to the new editions with an approval date on or after July 1, 2024, unless the manufacturer elected to transition before the effective date under Department rule 70.70(a)(5)(B).
    • Construction begun on or after July 1, 2024 must comply with the new code editions and approved design packages.
    • Construction begun before July 1, 2024, or before a manufacturer's effective transition date, must meet the stated completion, inspection, and labeling deadline to remain eligible for a Texas decal.

    effective date: 2024-07-01 · International Building Code: 2021 Edition (including appendices C, F, and K) · International Residential Code: 2021 Edition (including appendices AG, AH, AK, AP, AQ, and AT) · International Fuel Gas Code: 2021 Edition · International Mechanical Code: 2021 Edition · International Plumbing Code: 2021 Edition · International Energy Conservation Code: 2015 Edition · National Electrical Code: 2020 Edition · International Existing Building Code: 2021 Edition (for alterations of portable industrialized buildings)

    “July 1, 2024, all industrialized housing and buildings, modules, and modular components shall comply with the following codes, as amended in §70.101 of the IHB Rules:”
    One more reviewed finding on this topic
    • Partial — Industrialized housing and buildings, modules, and modular components built for Texas under the Industrialized Housing and Buildings program.
      “Effective July 1, 2024, all industrialized housing and buildings, modules, and modular components shall comply with the following codes, as amended in §70.101 of the IHB Rules:”
  • Who permits septicMixed (with conditions)

    OSSF permitting, inspection, and administration throughout Texas.

    • TCEQ administers the program in areas where no local jurisdiction has been authorized.
    • A local governmental entity may administer the program only after an order, ordinance, or resolution is approved by TCEQ.
    • The authorized agent administers the program within its approved area of jurisdiction.
    • Local programs may adopt requirements more stringent than state minimums.
    “The authorized agent is responsible for the proper implementation of Texas Health and Safety Code, Chapter 366, 30 TAC Chapter 285, including reviewing OSSF permit applications, conducting inspections, investigating complaints, and more.”
    One more reviewed finding on this topic
    • Mixed — On-site sewage facilities, including septic systems, throughout Texas
      “TCEQ is not often the OSSF permitting authority. [...] The TCEQ regional office will be the permitting authority in locations where a local jurisdiction has not been authorized.”
  • Off-grid sanitationLimited

    Off-grid wastewater sanitation through an OSSF in Texas.

    • An OSSF generally requires a permit and approved plan before construction, installation, alteration, extension, repair, or operation.
    • A qualifying single-family dwelling on a tract of at least 10 acres may use the 10-acre permitting exemption only if every stated site-evaluation, setback, nuisance, groundwater, on-site disposal, and single-dwelling condition is met.
    • Local permitting authorities may impose requirements more stringent than state minimums.
    • Emergency repairs are exempt from permitting only for the listed repair types and must be reported in writing within 72 hours after repairs begin.

    10-acre exemption tract size: >= 10 acres (all TCEQ conditions must be satisfied) · 10-acre exemption OSSF setback: >= 100 feet from property line (all parts of the OSSF)

    “An OSSF may be exempt from permitting if it complies with all other requirements, including planning, construction, and installation standards of 30 TAC 285 AND meets the “10 acre rule”:”
    2 more reviewed findings on this topic
    • Limited — Use of an approved composting toilet as part of an off-grid sanitation setup serving property in Mills County, Texas
      “Technical Notes: An approved on-site sewage facility will be required for disposal of all other wastewater. Systems are Certified for liquid containment, odors, and solid end products. Classified for Day-use Park by NSF International. Restrictions: See Title 30 Texas Administrative Code, Chapter 285.34(f).”
    • Limited — Composting toilets used as on-site sewage facility treatment systems in Texas.
      “Composting toilets will be approved by the executive director provided the system has been tested and certified under NSF International Standard 41 (1999) or under any other standards approved by the executive director.”
  • Well permitLimited

    Drilling, equipping, operating, or completing a water well, or substantially altering a well or well pump, where the well is within a groundwater conservation district in Texas.

    • A groundwater conservation district must require a permit except as provided by Texas Water Code §36.117.
    • A district may not require a permit or permit amendment for maintenance or repair that does not increase production capability above the authorized or permitted production rate.
    • Permit applications must be in writing and sworn.
    • Whether a particular private well is exempt or subject to additional district requirements depends on the applicable groundwater conservation district's rules.

    permit application form: in writing and sworn

    “Except as provided by Section 36.117, a district shall require a permit for the drilling, equipping, operating, or completing of wells or for substantially altering the size of wells or well pumps.”
  • county zoning authorityLimited

    Texas counties adopting zoning regulations for specified unincorporated or otherwise specially defined areas.

    • Chapter 231 does not grant a general statewide county zoning power; authority is provided through geographically or subject-matter limited subchapters.
    • For Padre Island, the authority applies in Cameron or Willacy County outside a municipality and within two miles of a publicly owned park or recreational development, or within two miles of a beach, wharf, or bathhouse used by at least 500 persons annually.
    • Other Chapter 231 subchapters address special areas including the Amistad Recreation Area in Val Verde County, military zones, certain lakes, the El Paso Mission Trail Historical Area, Lake Somerville, and Falcon Lake in Zapata County.
    • The cited statute was enacted effective September 1, 1987; the Falcon Lake subchapter was added effective June 15, 2007, and amended effective September 1, 2009.

    Padre Island distance from publicly owned park or recreational development: <= 2 miles (Area must be outside a municipality and in Cameron or Willacy County.) · Padre Island distance from beach, wharf, or bathhouse: <= 2 miles (The beach, wharf, or bathhouse must be used by at least 500 persons annually.)

    “This subchapter applies to the areas of Padre Island located in Cameron or Willacy County and located: (1) outside a municipality but within two miles of a publicly owned park or recreational development; or (2) within two miles of a beach, wharf, or bathhouse used by at least 500 persons annually.”
    One more reviewed finding on this topic
    • Limited — County zoning authority over unincorporated land in Texas, where a specific statutory grant applies.
      “As you suggest, a county has very limited and specific zoning authority, and none that may be used to regulate construction or operation of the proposed facility.”
  • county building authorityLimited

    Texas counties adopting and enforcing fire-code building permits for specified buildings in unincorporated areas and applying residential building-code standards in certain counties.

    • Under Section 233.061, the county must have a population over 250,000 or be adjacent to a county with a population over 250,000.
    • Under Section 233.062, the fire code applies only to commercial establishments, public buildings, and multifamily residential dwellings consisting of four or more units constructed in an unincorporated area.
    • The fire code does not apply to an industrial facility having a fire brigade that conforms to Occupational Health and Safety Administration requirements.
    • A covered applicant must submit a plan and a commissioners-court-set application fee; the county must issue or deny the permit within 30 days, and failure to act within 30 days approves the construction for purposes of the subchapter.
    • The fire code must conform to the International Fire Code or Uniform Fire Code as those codes existed on May 1, 2005, or establish protective measures exceeding those standards; later editions may be adopted.
    • Residential standards under Section 233.152 apply only if the county adopts a resolution or order and the county is within 50 miles of an international border or has a population over 100.
    • Those residential standards apply only to new single-family-house or duplex construction beginning after September 1, 2009; manufactured or modular structures governed by Occupations Code Chapters 1201 or 1202 are excluded from the definition of new residential construction.
    • A municipality's building code controls in its extraterritorial jurisdiction, and Section 233.152 does not authorize county prior approval of new residential construction or county zoning regulations.
    • Fire-code inspection and permit fees may be charged under a fee schedule based on building type, limited to amounts necessary to administer and enforce the subchapter; inspection fees must be reasonable and reflect approximate inspection costs.

    county population threshold for fire-code authority: > 250000 persons (A county adjacent to a county over 250,000 also qualifies.) · multifamily residential dwelling threshold: >= 4 units (The fire code applies only to covered buildings constructed in an unincorporated area.) · residential-code border distance: <= 50 miles (Alternative qualification is county population over 100.) · application decision period: 30 days (If the commissioners court does not issue or deny the permit within 30 days after receiving the application and fee, construction is approved for purposes of the subchapter.) · residential standards effective construction date: > 2009-09-01 (Applies only to new residential construction that begins after September 1, 2009.)

    “The commissioners court of a county with a population of over 250,000 or a county adjacent to a county with a population of over 250,000 may adopt a fire code and rules necessary to administer and enforce the fire code. [...] The fire code applies only to the following buildings constructed in an unincorporated area of the county: (1) a commercial establishment; (2) a public building; and (3) a multifamily residential dwelling consisting of four or more units.”
    One more reviewed finding on this topic
    • Limited — County fire-code adoption and building-permit authority for specified buildings in unincorporated areas of qualifying Texas counties, including multifamily residential dwellings of four or more units.
      “The commissioners court of a county with a population of over 250,000 or a county adjacent to a county with a population of over 250,000 may adopt a fire code and rules necessary to administer and enforce the fire code.”

Still unanswered

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

  • Inspections — Inspections for new residential construction in unincorporated Mills County.
  • Certificate of occupancy — Certificates of occupancy for residential buildings in Mills County.
  • Local zoning — Aggregate local zoning controls within Mills County, including any incorporated municipalities and unincorporated areas.
  • Mandatory utility hookup — Water and wastewater utility connection requirements in Mills County, Texas.
  • Short-term rentals — Short-term rentals in Mills County, Texas.

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, Texas

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

Mills County scores 70/100 on the Bolthole Index, a strong county profile. Its strengths: low administrative friction for a quiet rural property and sparse surroundings — about 4,844 people within 15 miles. Watch-outs: workable self-sufficiency basics (30.8″/yr rainfall).

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

Mills County requires a building permit only in limited cases (such as floodplains or specific zones), and it has no county-wide zoning. Onsite septic is permitted by Mills County OSSF program (TCEQ authorized agent) under Tex. Health & Safety Code Ch. 366 / 30 TAC 285. 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.

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

Living in an RV on your own land in Mills County is allowed: Unincorporated Mills County: no county rule sets this, because Mills County has adopted no county zoning ordinance (Texas law lets some counties zone, but this one has not). The county legal census found no county zoning ordinance, citing statutes.capitol.texas.gov. Septic, floodplain, subdivision and health rules still apply; cities and towns set their own rules inside their limits. Chapter 231 does not grant a general statewide county zoning power; authority is provided through geographically or subject-matter limited subchapters. A tiny home is allowed. Confirm with the county before relying on it.

How much does land cost in Mills County, Texas?

Land in Mills County runs about $3,731 per acre, based on the latest county data.

What is the water situation in Mills County?

Mills County gets about 30.8" of rain a year, with severe drought in roughly 29.7% of years.

How remote is Mills County?

A typical private-land location has about 4,844 people within 15 miles and 3,565,973 within 100 miles. These radius catchments are the published fallback where road routing is unavailable.

How Mills compares in Texas

Compare side-by-side →See all 254 Texas counties ranked →