Unincorporated Greer County, Oklahoma does not require a building permit to construct or alter a single-family home, duplex, barn, shed or attached carport1. The county's official offices list has no building, planning or zoning department, so no county ordinance sets minimum home size, setbacks or where you can place an RV or tiny home23. Septic systems still need an Oklahoma DEQ Authorization to Construct before installation4.
At a glance
- Building permit
- Not required in unincorporated Greer County for a home, duplex, barn, shed or attached carport15
- Zoning
- No county zoning ordinance23
- Septic
- Oklahoma DEQ Authorization to Construct required before installation4
- RV living
- Not restricted by county zoning (none exists)3
- Tiny home
- Not restricted by county zoning (none exists)3
- Owner-builder
- No county permit to be exempt from; you can build your own home6
- Minimum home size
- None set by the county3
- Wells
- No permit for domestic household use; non-domestic use needs OWRB review7
Who to call
Septic permits
Oklahoma DEQ Environmental Complaints & Local Services (On-Site Sewage Programs)
On-site sewage (septic) system soil tests, Authorization to Construct, and final inspections for Greer County, since Oklahoma has no separate county septic authority
707 N Robinson, Oklahoma City, OK 73102
Also useful
Greer County Commissioners' Office (Commissioners' Secretary)
General Greer County government contact and the elected Board of County Commissioners; the county's office listing shows no building, planning/zoning, or floodplain department to route those questions to instead
106 E. Jefferson, 2nd floor, Mangum, OK 73554
Contact details are copied from each office’s official page and were checked against it on September 24, 2026.
Do you need a building permit in Greer County, Oklahoma?
No. Greer County's official offices list includes no building or permit department, consistent with how unincorporated Oklahoma counties generally operate5. Oklahoma law is explicit on top of that: nothing requires a person to get a State Fire Marshal permit "for the construction or alteration of a single-family dwelling, duplex residential dwelling, barn, shed, or carport attached to a single-family dwelling, or duplex residential dwelling when such structure is located in an unincorporated area of a county"1. That exemption is specific to State Fire Marshal permits, not a blanket promise that no rule ever applies, but Greer County has adopted no local building-permit ordinance of its own to fill the gap5. Statewide minimum construction codes still exist in the background: Oklahoma is on the 2018 code editions until September 14, 2026, when the 2024 International codes take over, and in unincorporated areas the Construction Industries Board enforces the electrical, mechanical, plumbing and fuel-gas portions of those minimum codes even though there is no local building-permit office to administer the rest8.
Who do you call about permits and county government in Greer County?
There is no Greer County building, codes, planning or zoning office to call, because none appears on the county's own office listing52. For general county business, including anything routed through the elected Board of County Commissioners, the Commissioners' Office is the county's front door9. If your project involves electrical, plumbing, mechanical or fuel-gas work, that falls under the state's Construction Industries Board minimum codes rather than a county office8. If a project instead needs a State Fire Marshal permit (commercial construction, for example), those are handled through the state's online plan-review portal, not by mail or email10. Inside Mangum, Granite, Willow or another incorporated town, check with that town directly: Greer County's census note indicates towns like Mangum issue their own building permits within their limits5.
Does Greer County have zoning?
No. Greer County has no county zoning ordinance, and Oklahoma law only grants zoning power to certain counties in the first place3. Because there is no zoning ordinance, there is no county rule on minimum dwelling size, minimum lot size, setbacks, lot coverage, building height, or where an accessory dwelling, RV, tiny home or manufactured home can go on unincorporated land in Greer County3. That is an absence of county regulation, not a guarantee against every rule: deed restrictions, lender requirements, and state rules on manufactured-home installation can still apply, and Oklahoma law separately exempts "the usual farm buildings for agricultural purposes" from county zoning authority where it exists11. If you buy land expecting to subdivide it later, Oklahoma's statewide rule for residential development outside a municipality still requires the state to approve any plat before it is recorded, sold, or built on, and a county clerk cannot record a residential plat with a lot smaller than 2.5 acres without that approval stamp12.
How do septic permits work in Greer County?
Oklahoma has no separate county septic authority; the Department of Environmental Quality runs the on-site sewage program statewide, including in Greer County13. Before installing a new system or modifying an existing one, you must purchase and receive a DEQ Authorization to Construct, which is assigned to the local DEQ Environmental Specialist based on where the property sits4. Every new or modified system must then be inspected and approved by DEQ, or installed, self-inspected and approved by a certified installer who files the paperwork with DEQ within 15 days14. Soils are the reason to plan ahead here: only about 5.7% of Greer County's soils are rated as free of severe limits for a conventional septic drain field, so most sites in the county should expect a soil and percolation test to push them toward an aerobic, drip-irrigation or lagoon system rather than a standard trench field15. The local DEQ Environmental Specialist reviews all of this and issues the paperwork16.
Can you live in an RV or tiny home on your land in Greer County?
Nothing in Greer County's own rules stops it, because the county has no zoning ordinance to restrict RV, tiny-home or manufactured-home occupancy on unincorporated land3. That is different from a state law affirmatively guaranteeing the right: it simply means no county rule currently addresses it, so check again before you buy if the county adopts zoning later. A manufactured home you install is treated as a permanent installation once it is occupied, and must follow HUD's federal installation standards or the manufacturer's DAPIA-approved instructions regardless of the county's lack of zoning17. Inside an incorporated town such as Mangum, Granite or Willow, town rules apply instead of this county-level answer, so confirm directly with the town if your land is inside its limits.
Building a home in Greer County: the steps, in order
- Confirm your parcel is in unincorporated Greer County rather than inside Mangum or another town, since towns issue their own permits and this guide's answers are for unincorporated land only5.
- Because there is no county building permit to apply for, you can start planning construction directly; no permit exists to require you to hire a licensed general contractor either6.
- Order your DEQ soil and percolation testing and file the Report for On-Site Sewage early, since the results determine what septic system your site allows4.
- Purchase and obtain your DEQ Authorization to Construct for the septic system before installation begins4.
- Line up licensed electrical, plumbing, mechanical and fuel-gas work; those trades fall under Construction Industries Board minimum codes even though the home itself needs no building permit8.
- If your driveway will connect to a state highway, apply for an ODOT driveway permit and do not start work in the right-of-way until it is approved18.
- If you are drilling a well, know that domestic household use needs no OWRB water permit, but irrigation over 3 acres or other commercial and non-domestic uses do7.
What to check before you buy land in Greer County
Water: a domestic well needs no OWRB water permit, but if you plan to irrigate more than 3 acres, run livestock beyond the land's grazing capacity, or use water for a business, that non-domestic use is regulated and may require an intent-to-drill authorization7. Septic and soils: with only about 5.7% of Greer County's soils free of severe limits for a conventional drain field, budget for a DEQ soil test and likely an engineered system rather than assuming a standard trench field will work15. Flood: if any part of your land is in a regulatory floodplain, Oklahoma requires a permit application from the floodplain administrator, with fees, plans and elevation data, before development begins19. Drought and climate: Greer County has spent roughly half its recent years (50.3%) in severe drought, worth weighing for any well, pond or irrigated garden plans20. Access: a driveway onto a state highway needs an approved ODOT Driveway Agreement before any work starts in the right-of-way18. Taxes: Greer County's effective property tax rate runs about 0.6%, with a median annual property tax bill near $5902122.
Watch-outs
- Greer County's own office listing shows no building, planning/zoning, or floodplain department; that is an absence of a county office, not proof no rule can ever apply, so confirm with the Commissioners' Office before relying on it92.
- The State Fire Marshal permit exemption for single-family homes, duplexes, barns, sheds and attached carports applies only to unincorporated Greer County and only to State Fire Marshal permits; it does not exempt electrical, plumbing, mechanical or fuel-gas work from Construction Industries Board minimum codes18.
Sources
- Oklahoma Statutes, quoted and re-checked
- Greer County official offices directory (OKCounties.org) (2026 county census)
- Oklahoma law on county zoning and building authority
- On-Site Sewage Information, quoted and re-checked
- Greer County official offices directory (OKCounties.org) (2026 county census)
- Oklahoma law on county zoning and building authority
- Apply for a Water Permit, quoted and re-checked
- Oklahoma Uniform Building Code Commission, quoted and re-checked
- Greer County Commissioners' Office (Commissioners' Secretary) (greer.okcounties.org)
- Plan Reviews (Oklahoma statewide rule), quoted and re-checked
- FAQs - Counties and Townships Authority to Zone, Permit, and Approve Certain Green Energy Construction Projects, quoted and re-checked
- Oklahoma Statutes, Title 27A — Environment and Natural Resources (Oklahoma statewide rule), quoted and re-checked
- Environmental Complaints & Local Services, quoted and re-checked
- On-Site Sewage Information, quoted and re-checked
- Share of soils without severe limits for a conventional septic drain field (USDA SSURGO): Bolthole Index county data
- Oklahoma DEQ Environmental Complaints & Local Services (On-Site Sewage Programs) (oklahoma.gov)
- Title 765 Oklahoma Used Motor Vehicle and Parts Commission Rules and Regulations (Oklahoma statewide rule), quoted and re-checked
- Instructions for Driveway Permit Application, quoted and re-checked
- Oklahoma's Floodplain Management 101, quoted and re-checked
- Share of years in severe drought: Bolthole Index county data
- Effective property tax rate: Bolthole Index county data
- Median property tax bill: Bolthole Index county data
Written September 24, 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.