Building permits, zoning and septic rules across Oregon’s counties

At a glance

Residential building permits

34 counties require them; 1 is listed as limited; the 1 listed no-permit exception needs confirmation.²⁸³

Zoning

36 counties have zoning; 0 have neither zoning nor residential building permits.⁴⁹

Septic permits

DEQ directly serves Curry, Jackson and Josephine; local jurisdictions serve the other counties.⁵

RV living

24 counties have an answer: 2 allowed, 2 temporary-only, 17 limited and 3 prohibited, within the stated conditions.⁶

Tiny homes

13 counties have an answer: 2 allowed, 9 limited and 2 prohibited, depending on the dwelling type and location.⁷

Owner-builder

A narrow exemption covers ceiling heights, room sizes and temperature requirements; a building permit is still required.¹⁰

Water and wells

Domestic groundwater use has an exemption, but special groundwater restrictions and well-construction requirements still matter.¹¹¹²

Property tax

Median county effective rate: 0.8%; median county tax bill: $2,520 per year.¹³

Who to call

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

Which Oregon counties don’t require a building permit?

Oregon has a statewide building code, including a residential specialty code for houses and townhouses.¹¹⁴ The county figures below concern unincorporated land; project-specific building permits, zoning and land-use allowances must be checked with the local jurisdiction.²¹⁵

Residential building permits are listed as required in 34 counties and limited in 1, Yamhill County.²⁸ We could not confirm the no-permit classification for Washington County; ask the local building department before relying on that exception.³¹⁵ Use the Oregon no-building-codes comparison as a starting point, then confirm the parcel’s building-permit requirements.³

Oregon’s owner-builder exemption covers ceiling heights, room sizes and specified temperature requirements, but still requires a building permit; it is not a general permission to build without inspections or codes.¹⁰ The owner-builder county list helps narrow the search, while eligibility follows the state’s conditions.¹⁰

Which Oregon counties have no zoning?

None of Oregon’s 36 counties is listed as having no countywide zoning, and no county is listed as having neither zoning nor residential building permits.¹⁶⁹ Oregon’s statewide zoning map represents local zoning; local governments remain the authorities for parcel-level determinations and ordinance administration.¹⁷

Resource-land zoning can change the land-buying calculation: the statutory minimum parcel sizes are generally 80 acres for exclusive farm use land that is not rangeland, 160 acres for exclusive farm use rangeland and 80 acres for designated forestland, subject to statutory exceptions and qualifying smaller county standards.¹⁸ Those resource-zone standards are not a statewide minimum for every residential lot.¹⁸ Ask the local planning office about the parcel’s district and proposed dwelling before treating acreage alone as an answer.¹⁷

Who issues septic permits in Oregon?

The Oregon Department of Environmental Quality directly issues residential and small-business septic permits in Curry, Jackson and Josephine counties through its Medford office; DEQ contracts with local jurisdictions in the other 33 counties.⁵ DEQ’s residential septic page links to the local permitting-authority contacts, so start there rather than assuming the building department also handles septic.¹⁹

An undeveloped site that has never received septic approval needs a site evaluation, and new septic construction requires a construction permit; alterations and repairs also fall under septic permitting.²⁰ DEQ requires an affirmative Land Use Compatibility Statement before issuing a construction permit for new construction or alterations.²⁰

A composting toilet does not remove the need for an approved wastewater treatment system for household water, and a building within a sewer district still needs a sewer connection.²¹²² Plan the wastewater solution alongside zoning approval, rather than treating off-grid sanitation as an automatic exemption.²⁰²¹

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

Oregon has county-level RV answers for 24 counties: 2 allow qualifying uses, 2 allow only temporary occupancy, 17 have limited uses and 3 prohibit the covered use; the remaining 12 have no confirmed county-level answer.⁶ Umatilla County allows an RV dwelling option in its Mountain Residential zone with zoning approval, while Lincoln County allows qualifying RV uses under applicable conditional-use provisions.⁶ Compare the RV-living county list, paying attention to each use’s conditions.⁶

Oregon’s rural RV rental law applies when a county elects to allow the use on qualifying property with an existing owner-occupied primary dwelling; it does not generally authorize an RV home on an empty rural parcel.²³

Tiny-home answers cover 13 counties: 2 allowed, 9 limited and 2 prohibited; 23 remain unconfirmed.⁷ Klamath County allows code-compliant small dwellings, and Curry County allows qualifying manufactured tiny homes on permanent foundations.⁷ The tiny-home county list distinguishes these uses from homes on wheels.⁷

Where are the best Oregon counties for a bolthole?

Union County leads the Bolthole Index at 71, followed by Umatilla County at 68, Jefferson County and Polk County at 65, Benton County, Klamath County and Morrow County at 63, and Baker County at 62; all of these counties require residential building permits and have zoning.²⁴ A high score therefore does not mean permission to build or occupy an RV without local approval.²⁴⁶

The median county farmland value is $4,773 per acre, with Harney County at $1,268 and Grant County at $1,324; these are farmland values, not asking prices for ready-to-build lots.²⁵ Oregon’s median county effective property-tax rate is 0.8%, and the median county property-tax bill is $2,520 annually; neither figure is a quote for a particular parcel.¹³

What should you check about Oregon water, wells and road access?

Oregon’s domestic groundwater-use exemption covers use up to 15,000 gallons per day, but the exemption can be limited in a Critical Groundwater Area; 17 counties overlap a special groundwater management regime.¹¹ An exempt water use is a different question from permission to construct a well: an owner doing well work without being a licensed and bonded well constructor needs a landowner well permit before starting.¹²

The landowner permit fee is $550, and the required bond or irrevocable letter of credit is $10,000.¹² Oregon Water Resources Department’s Well Construction and Compliance program oversees well standards and keeps well reports; ask that office about the proposed well and the local watermaster about the water source.²⁶

For a new driveway onto an Oregon state highway, or a change in use of an existing connection, written ODOT permission is required through the highway approach permit process.²⁷ There is no application-submission fee, but design, construction, insurance, bond and other associated costs may apply.²⁷

Watch-outs

• Confirm the project’s jurisdiction before applying: the county counts concern unincorporated land, and the local jurisdiction answers building-permit, zoning and land-use questions.²¹⁵
• Oregon’s owner-builder exemption is narrow and still requires a building permit.¹⁰
• Oregon’s agricultural structural-code exemption excludes dwellings and qualifying flood-regulated structures, and electrical, plumbing and mechanical work remains subject to the applicable codes and building-trade permits.²⁸
• We could not confirm a general statewide setback or lot-coverage limit; ask the local planning office for parcel-specific zoning and land-use allowances.¹⁵
• An RV or tiny-home answer applies to the described use and location; counties without an answer should not be treated as allowing occupancy.⁶⁷

Sources

1. Oregon: Oregon State Building Code, quoted and re-checked
2. Bolthole Index county rulebook, 36 Oregon counties, as of October 10, 2026: Oregon counties that require a residential building permit in unincorporated areas
3. Bolthole Index county rulebook, 36 Oregon counties, as of October 10, 2026: Oregon counties that do not require a residential building permit in unincorporated areas
4. Bolthole Index county rulebook, 36 Oregon counties, as of October 10, 2026: Oregon counties with county zoning
5. Oregon: Residential Septic Permitting, quoted and re-checked
6. Bolthole Index county rulebook, 36 Oregon counties, as of October 10, 2026: Oregon counties' answers on living in an RV on your own land
7. Bolthole Index county rulebook, 36 Oregon counties, as of October 10, 2026: Oregon counties' answers on living in a tiny home on your own land
8. Bolthole Index county rulebook, 36 Oregon counties, as of October 10, 2026: Oregon counties that require a residential building permit only in some cases (for example floodplain or certain structures)
9. Bolthole Index county rulebook, 36 Oregon counties, as of October 10, 2026: Oregon counties with neither a residential building permit nor county-wide zoning
10. Oregon: 2023 Oregon Residential Specialty Code - ORS 455.320 reprinted, quoted and re-checked
11. Oregon water rights and groundwater management: National Agricultural Law Center and Bolthole Index groundwater review
12. Oregon: Landowner Constructed Wells, quoted and re-checked
13. Bolthole Index county rulebook, 36 Oregon counties, as of October 10, 2026: Median of Oregon's county effective property tax rates and median county property tax bills
14. Oregon: Residential Structures Code Program, quoted and re-checked
15. Oregon Building Codes Division (oregon.gov)
16. Bolthole Index county rulebook, 36 Oregon counties, as of October 10, 2026: Oregon counties with no county-wide zoning
17. Oregon: Maps, Data and Tools, quoted and re-checked
18. Oregon: Oregon Revised Statutes, Chapter 215, quoted and re-checked
19. Oregon Department of Environmental Quality — Onsite Wastewater Program (oregon.gov)
20. Oregon: Housing and Onsite Wastewater Management, quoted and re-checked
21. Oregon: What do I do with the finished material?, quoted and re-checked
22. Oregon: What do I do with the finished material?, quoted and re-checked
23. Oregon: Oregon Revised Statutes, ORS 215.490, quoted and re-checked
24. Bolthole Index county rulebook, 36 Oregon counties, as of October 10, 2026: The 8 highest-scoring Oregon counties on the Bolthole Index (off-grid and homestead land score out of 100), with each one's building-permit, zoning and septic answers
25. Bolthole Index county rulebook, 36 Oregon counties, as of October 10, 2026: Median farmland value per acre across Oregon's counties (USDA census, the middle county's value; USD/acre), with the five least expensive counties
26. Oregon Water Resources Department — Well Construction and Compliance (oregon.gov)
27. Oregon: Access Management, quoted and re-checked
28. Oregon: Oregon Revised Statutes, Chapter 455, 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.