Unincorporated Dallas County, Missouri does not require a building permit for a home1, but Buffalo requires city building permits and applies zoning districts23. Dallas County Health Department requires septic permits for new systems and changes4. We could not confirm a county zoning ordinance, so ask the Dallas County Clerk before relying on an unincorporated parcel as unrestricted56.
At a glance
- Building permit (site-built home)
- Not required in unincorporated Dallas County; required inside Buffalo12
- County zoning
- No county zoning ordinance confirmed; ask the County Clerk before relying on that56
- Septic permit
- Required before construction, repair or replacement, through the County Health Department78
- Septic soils
- Only 7.7% of county soils rated free of severe limits for a conventional drain field9
- Driveway onto a state highway
- Requires a MoDOT right-of-way permit10
- Floodplain development
- Requires a permit if the parcel is in a mapped floodplain11
- Private well work
- Contractor well and pump work requires state permits; a landowner may install their own without one12
- Manufactured home installation
- Must use a state-licensed installer unless you install it yourself on your own property13
Who to call
Septic permits
Dallas County Health Department (Environmental Health)
Onsite wastewater (septic) construction permits for Dallas County
901 W Main, Buffalo, MO 65622
Also useful
General county administration, recording and elections questions, and the first point of contact since Dallas County has no building or zoning department
Roads & driveways
Dallas County Road & Bridge Department
County-maintained road questions; driveways onto state highways instead need a Missouri Department of Transportation permit
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 Dallas County means bringing your own water and power. The kit we’d start with:
- Water Crystal Quest Filter any source — well, rain, or creek — to drinking-clean.
- Power Bluetti Solar generators and home battery backup for living off the grid.
- Septic Soil percolation test kit Run your own perc test before paying an engineer — the first thing a septic office asks about.
- Water Well water test kit Bacteria, nitrates, hardness — know what the well on a parcel is really pumping.
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 Dallas County, Missouri?
Unincorporated Dallas County, Missouri does not require a building permit for a home1. That answer changes inside Buffalo: the city requires a building permit and inspections and has adopted construction codes2. Where a political subdivision requires inspections for a new one- or two-family home, the engineer who sealed the permit plans may perform the footing, foundation, wall and framing inspections using that jurisdiction's procedures and forms14. If you plan to install a manufactured home, the installer must hold a state commission-issued license unless you install the home on your own property for your own occupancy13. We could not confirm a Dallas County certificate-of-occupancy rule or a separate owner-builder exemption, so ask the Dallas County Clerk before work begins156.
Who handles permits and questions in Dallas County?
For an unincorporated parcel, start with the Dallas County Clerk because we could not confirm a county building or zoning office6. The Dallas County Health Department's Environmental Health division, at 901 W Main in Buffalo, handles onsite wastewater permits1617. Construction inside Buffalo follows the city's building-permit, inspection and zoning rules instead of the unincorporated-county answer23. Questions about county-maintained roads go to the Dallas County Road & Bridge Department18. A driveway or approach within Missouri Department of Transportation right-of-way needs a MoDOT permit, while we could not confirm the rule for an entrance connecting only to a county or private road10.
Does Dallas County have zoning?
We could not confirm a countywide zoning ordinance for unincorporated Dallas County5. Missouri allows qualifying counties to adopt zoning for unincorporated territory only after voter approval, but that authority does not establish what applies to a particular Dallas County parcel19. Ask the Dallas County Clerk before treating land as unrestricted6. We also could not confirm county rules for private-land RV occupancy, tiny homes, minimum dwelling size, lot size, setbacks or accessory dwellings. Buffalo is different: land and buildings inside the city must follow the uses allowed in the applicable zoning district3. Missouri's agricultural exclusions cover qualifying farming uses and farm structures outside mapped flood-hazard areas, but do not remove independent floodplain, septic or environmental requirements20.
How do septic permits work in Dallas County?
The Dallas County Health Department is the county's septic authority under a local ordinance17. Dallas County requires a registered installer for new construction, repairs and replacements, and requires a permit before construction or changes; confirm any claimed exemption before work begins4. Missouri's standards are minimums, so the county ordinance may be more restrictive21. Off-grid sanitation does not allow untreated discharge into a road ditch or onto the ground22. Only 7.7% of Dallas County soils are rated free of severe limits for a conventional drain field, so arrange a site evaluation before choosing a homesite or system9. For an existing home, a private licensed inspector can evaluate the system before closing because local health agencies generally no longer perform transfer inspections23.
Can you live in an RV or tiny home on your land in Dallas County?
We could not confirm whether Dallas County allows full-time RV or tiny-home occupancy on private land, so ask the Dallas County Clerk before buying for that use6. Missouri Department of Conservation areas have a separate camping-permit proposal for temporary overnight stays at specified locations, but the source did not state when that proposal would take effect24. That department-area proposal does not answer whether you may live in an RV on your own Dallas County land24. Inside Buffalo, a tiny home or RV use must also fit the city's applicable zoning district3. Any occupied tiny home needs an approved wastewater solution; Dallas County requires a septic permit before new construction or changes4.
Building a home in Dallas County: the steps, in order
- Confirm whether the parcel is unincorporated or inside Buffalo; unincorporated homes do not require a county building permit, while Buffalo requires a city permit, inspections and compliance with its zoning district123.
- Ask the Dallas County Clerk to confirm setbacks, occupancy and other parcel-specific rules that we could not confirm6.
- Evaluate the soil because only 7.7% of Dallas County soils are rated free of severe limits for a conventional drain field9.
- Contact Dallas County Health, use a registered installer, and obtain the septic permit or confirm an exemption before work begins164.
- For a private well, use properly permitted well and pump contractors unless the landowner will use Missouri's self-installation exception12.
- Apply to MoDOT before work within state right-of-way; ask Road & Bridge about county-road access1018.
- If the site is in a mapped floodplain, obtain the development permit; work in a regulatory floodway also requires an engineering No-Rise Certificate first11.
What to check before you buy land in Dallas County
Water and septic: only 7.7% of Dallas County soils are rated free of severe limits for a conventional drain field, so get a site evaluation before relying on a standard system9. Missouri requires permits for contractor well and pump work but allows landowners to install their own well or pump without one12. Terrain: 73.5% of the land has a slope of 15% or less, and 49.6% is wooded2526. Access: a driveway within MoDOT right-of-way needs a permit, while the county-road access rule remains unconfirmed10. Costs: the effective property tax rate is about 0.5%, and the median annual property tax bill is about $7262728. Flood risk: development in a mapped floodplain requires a permit, including qualifying farm structures that lose the agricultural land-use exclusion inside mapped flood-hazard areas1129.
Watch-outs
- Dallas County's government directory is hosted on the Buffalo Area Chamber of Commerce website; call the Dallas County Clerk to verify any rule before relying on it6.
- We could not confirm Dallas County rules for zoning, private-land RV use, tiny homes, minimum dwelling size, or setbacks; ask the County Clerk before relying on a proposed use56.
- Buffalo requires city building permits and inspections even though a home in unincorporated Dallas County does not require a county building permit21.
- Missouri Department of Conservation's camping-permit proposal applies to department areas, not private land, and its effective date was not stated24.
- Most of Dallas County's soils are poorly suited to a conventional septic drain field; get a site evaluation before you buy or plan a home's location9.
Sources
- State of Missouri - County Building Codes for Missouri (data.mo.gov) (2026 county census)
- Building Department | Buffalo, MO, quoted and re-checked
- City Code 2024, quoted and re-checked
- Environmental Health, quoted and re-checked
- Dallas County MO Government Officials directory (2026 county census)
- Dallas County Clerk (buffalococ.com)
- OWTS Construction Permit Process (2026 county census)
- Environmental Health — Dallas County Health Department, quoted and re-checked
- 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
- Permits — Missouri Department of Transportation, quoted and re-checked
- Floodplain Forms, quoted and re-checked
- Water Wells - PUB2945, quoted and re-checked
- RSMo 700.656 — Installers to be licensed by the commission, quoted and re-checked
- Missouri Revised Statutes § 67.490, quoted and re-checked
- (2026 county census)
- Dallas County Health Department (Environmental Health) (dallascountyhealth.com)
- Administration — Dallas County Health Department, quoted and re-checked
- Dallas County Road & Bridge Department (buffalococ.com)
- RSMo § 64.090 — Planning and zoning powers of county commission (Missouri statewide rule), quoted and re-checked
- RSMo § 64.620 — Building restrictions — limitations on regulations, quoted and re-checked
- Onsite Wastewater Treatment, quoted and re-checked
- Onsite Wastewater Treatment, quoted and re-checked
- Onsite Wastewater Treatment System Inspections Versus Evaluations (Missouri statewide rule), quoted and re-checked
- 3 CSR 10-11.140: Camping, quoted and re-checked
- Share of land at 15% slope or less: Bolthole Index county data
- Wooded share of land: Bolthole Index county data
- Effective property tax rate: Bolthole Index county data
- Median property tax bill: Bolthole Index county data
- RSMo § 64.890 — Building and land use restrictions — exemptions — limitations on use of powers, quoted and re-checked
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.