Bolthole Index

Honolulu County, Hawaii

Building permits, zoning and septic rules in Honolulu County, Hawaii

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Honolulu County, which covers the entire island of Oahu, requires a building permit for residential construction under Revised Ordinances of Honolulu Chapter 16, enforced by the City and County of Honolulu's Department of Planning and Permitting1. Zoning is countywide under Chapter 21, the Land Use Ordinance, administered by the same department's Land Use Permits Division2. Septic and other individual wastewater systems are permitted by the State Department of Health, not the county, and Hawaii is phasing out new cesspools while requiring existing ones to convert by 20503.

At a glance

Building permit
Required under ROH Chapter 16/1814
Zoning
Yes, Chapter 21 Land Use Ordinance, countywide25
Owner-builder exemption
Yes, register under HRS 444-9.1; no sale or lease within 1 year67
Septic (IWS) permits
State Dept. of Health Wastewater Branch, not the county; new cesspools banned3
State land-use district
Every parcel is Urban, Rural, Agricultural or Conservation under state law8
Residential setbacks
General guideline: 10 ft front, 5 ft side/rear9
Lot coverage
Impervious surface generally capped at 75% of lot area10

Who to call

Building permits

Department of Planning and Permitting — Customer Service Division

Reviews and issues building permits for single-family and two-family homes, duplexes, and their accessory structures

(808) 768-8220

650 South King Street, Honolulu, HI 96813

Zoning

Department of Planning and Permitting — Land Use Permits Division

Administers the Land Use Ordinance (Chapter 21), Special Management Areas Ordinance (Chapter 25) and Shoreline Setbacks Ordinance (Chapter 26)

(808) 768-8015

650 South King Street, Honolulu, HI 96813

Health department

Hawaii State Department of Health — Wastewater Branch (Oahu/Main Office)

Permits, reviews and inspects individual wastewater systems (septic/IWS) and cesspool conversions for Oahu, including Honolulu County

(808) 586-4294

2827 Waimano Home Road, Ste 207, Pearl City, HI 96782

Contact details are copied from each office’s official page and were checked against it on September 29, 2026.

Do you need a building permit in Honolulu County (Oahu), Hawaii?

Yes. The City and County of Honolulu requires a building permit for construction work covered by its building code, and construction may proceed only after that permit is obtained14. All permitted work stays subject to inspection by the building official, and a final inspection is required before final occupancy11. No building may be used or occupied, and no change of occupancy classification made, until the Department of Planning and Permitting issues a certificate of occupancy12. One narrow exception: an agricultural building or structure built to meet Hawaii Revised Statutes 46-88, and declared with the City and County of Honolulu, does not need a building permit or a certificate of occupancy, though it still cannot have plumbing or electrical work1314.

Who issues building permits in Honolulu County, and how do you reach them?

The Department of Planning and Permitting's Customer Service Division reviews and issues building permits for single-family and two-family homes, duplexes, and their accessory structures15. Reach the department at 650 South King Street, Honolulu, HI 96813, and call (808) 768-8220 specifically for residential building permits15. You can apply for an Instant Online Permit for many eligible single-family projects, or submit a full Internet Building Permit Application and receive an IBP number for projects that need plan review through the One-Stop Permit Center or Electronic Plan Review16. Permit fees are based on your project's fair-market labor and materials value rather than a flat schedule, so use the department's online fee calculator to estimate cost before you apply17.

Does Honolulu County have zoning?

Yes, countywide. Chapter 21 of the Revised Ordinances of Honolulu, the Land Use Ordinance, sets zoning districts and precincts, permitted uses, and zone-change procedures across all of Oahu, administered by the Department of Planning and Permitting's Land Use Permits Division25. A separate, older layer of state law also applies everywhere in Hawaii: every parcel sits in one of four state land-use districts, Urban, Rural, Agricultural or Conservation, and county zoning operates within whichever district your parcel is in8. In the state's Rural district, lots generally carry a minimum size of half an acre, subject to statutory and county exceptions, well above what many Urban-district residential lots require8. For residential dwellings, the general Honolulu setback guideline is 10 feet from the front property line and 5 feet from the side and rear property lines, with larger side and rear yards required once floor area ratio exceeds 0.69. Total paved and impervious area, including driveways, generally cannot exceed 75% of the zoning lot for dwellings permitted after May 1, 201910. Minimum lot size and building height are both district-specific rather than one countywide number, so confirm both for your parcel's exact zoning district before you plan a build1819.

How do septic (IWS) permits work in Honolulu County?

Septic and other individual wastewater systems on Oahu are permitted by the Hawaii State Department of Health's Wastewater Branch, not by the City and County of Honolulu, and that jurisdiction only covers properties not already served by a sewer system320. Reach the Oahu/main office at 2827 Waimano Home Road, Ste 207, Pearl City, HI 96782, or by phone at (808) 586-429420. A licensed engineer must run a percolation test, survey the property, size the system, and submit plans to the Wastewater Branch, and no one may use a new or modified system until the director approves it in writing21. Filing fees run $100 for a new individual wastewater system and $25 for an addition or modification to an existing one, and the engineer must file a final inspection report within 30 days of completion2122. Hawaii bans new cesspools outright and requires every existing cesspool to be converted to an approved system by 2050, which is worth budgeting for now if a property you are considering still has one3. If a lot is within or near an available public sewer, state rules require connecting to that sewer instead of installing a private system23.

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

We could not confirm a specific Honolulu County rule that directly addresses RV, tiny-home or manufactured-home occupancy on private residential land; official Department of Planning and Permitting materials do not establish a rule either way, so confirm with the Land Use Permits Division before you plan around one5. Statewide, Hawaii law prohibits habitation in a parked vehicle on a public roadway, street or highway between 6:00 p.m. and 6:00 a.m., but on private property habitation is allowed only with the property owner's or occupant's authorization covering both parking and habitation, and a county may adopt its own ordinance that overrides this state rule24. A tiny home would still need to meet Honolulu's building permit, zoning and septic or sewer requirements like any other dwelling, since no separate tiny-home occupancy rule exists on the county's own pages12. If your land is agricultural and leased under Hawaii's agricultural-subdivision statute, be aware that no permanent or temporary dwelling, including a trailer or camper, may be built on that leased land at all25.

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

  1. Confirm your parcel's zoning district under Chapter 21 and its state land-use district (Urban, Rural, Agricultural or Conservation) with the Land Use Permits Division before you plan anything58.
  2. If you want to build or improve a home yourself, register for Hawaii's owner-builder exemption under HRS 444-9.1, and remember you cannot sell or lease the finished home within one year without triggering the presumption that it was built for sale67.
  3. Apply for your building permit through the Department of Planning and Permitting's Customer Service Division: use an Instant Online Permit if your single-family project qualifies, or submit a full Internet Building Permit Application otherwise1516.
  4. If your lot is not on sewer, apply separately to the State Department of Health Wastewater Branch for your septic (IWS) permit; a licensed engineer must evaluate the site and submit plans first2021.
  5. Schedule a well permit with the Commission on Water Resource Management if you plan to drill one; the work itself must be done by a C-57 licensed well driller26.
  6. Keep required construction records, contracts and proof of payment available for inspection while you build, and for three years after completion, making them available within seven business days of any request7.
  7. Pass your final building inspection and get your certificate of occupancy before you move in, and get the Wastewater Branch's written approval before you use a new septic system1221.

What to check before you buy land in Honolulu County

Find out which of Hawaii's four state land-use districts your parcel sits in, Urban, Rural, Agricultural or Conservation, before you assume county zoning tells the whole story; the state district can limit what the county is allowed to permit at all8. If the land is Agricultural and any dwelling matters to you, check whether it is leased under the state's agricultural-subdivision rules, which can bar any dwelling, including a trailer or camper, from the leased parcel entirely25. Ask the Department of Planning and Permitting whether the specific parcel has any pending violations or is in a flood zone, since either one blocks the fast Instant Online Permit path for a future home16. Budget for septic carefully: only about 13.1% of Honolulu County's sampled soil, under USDA data, carries no severe limitation for a conventional drain field, and if the property still has a cesspool, plan and budget for the state-mandated conversion by 2050273. Honolulu County (the island of Oahu) has a population density near 1,647 people per square mile and a typical home value around $858,250; property tax bills run about $2,482 a year at an effective rate near 0.3%, among the lowest in the country28293031.

Watch-outs

  • Hawaii bans new cesspools outright and requires every existing one to convert to an approved system by 2050; if a property you're considering still has a cesspool, get a cost estimate for that conversion before you close3.
  • We could not confirm a Honolulu County rule on living in an RV or tiny home on your own land; Hawaii's statewide vehicle-habitation law only clearly covers public roadways and requires the property owner's authorization on private land, and a county ordinance can override it, so confirm with the Land Use Permits Division directly245.
  • If your land is Agricultural and leased under Hawaii's agricultural-subdivision statute, no dwelling of any kind, including a trailer or camper, may be built on the leased parcel25.

Sources

  1. ROH Chapter 16 Building Code (2026 county census)
  2. Zone Change (2026 county census)
  3. Hawaii DOH Wastewater Branch - Individual Wastewater Systems (2026 county census)
  4. ROH Chapter 16 Building Code, quoted and re-checked
  5. Department of Planning and Permitting — Land Use Permits Division (honolulu.gov)
  6. Hawaii Revised Statutes 444-2.5 - Owner-builder exemption (2026 county census)
  7. Hawaii Revised Statutes §444-2.5 Owner-builder exemption, quoted and re-checked
  8. Hawaii Revised Statutes § 205-2, Districting and classification of lands (Hawaii statewide rule), quoted and re-checked
  9. Frequently Asked Questions, quoted and re-checked
  10. Frequently Asked Questions, quoted and re-checked
  11. ROH Chapter 16 Building Code, quoted and re-checked
  12. ROH Chapter 16 Building Code, quoted and re-checked
  13. Permit Exempt Agricultural Structures, quoted and re-checked
  14. HRS §46-88 Agricultural buildings and structures; exemptions from building permit and building code requirements (Hawaii statewide rule), quoted and re-checked
  15. Department of Planning and Permitting — Customer Service Division (honolulu.gov)
  16. Frequently Asked Questions, quoted and re-checked
  17. Frequently Asked Questions, quoted and re-checked
  18. Frequently Asked Questions, quoted and re-checked
  19. Frequently Asked Questions, quoted and re-checked
  20. Hawaii State Department of Health — Wastewater Branch (Oahu/Main Office) (health.hawaii.gov)
  21. Individual Wastewater Systems – Wastewater Branch, quoted and re-checked
  22. Chapter 11-62, Hawaii Administrative Rules (Unofficial) – Wastewater Branch, quoted and re-checked
  23. Chapter 11-62, Hawaii Administrative Rules (Unofficial) – Wastewater Branch (Hawaii statewide rule), quoted and re-checked
  24. HRS §291C-112: Certain uses of parked vehicles prohibited (Hawaii statewide rule), quoted and re-checked
  25. HRS §205-4.5, Permissible uses within the agricultural districts (Hawaii statewide rule), quoted and re-checked
  26. Hawaii Well Construction and Pump Installation Standards (Hawaii statewide rule), quoted and re-checked
  27. Share of soils without severe limits for a conventional septic drain field (USDA SSURGO): Bolthole Index county data
  28. Population density: Bolthole Index county data
  29. Typical home value (Zillow): Bolthole Index county data
  30. Median property tax bill: Bolthole Index county data
  31. Effective property tax rate: Bolthole Index county data

Written September 29, 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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County locator

Honolulu County in Hawaii

48
County map
Honolulu County highlighted among the Hawaii counties · colored by Index score

How Honolulu County scores

Seclusion40100% ev.
Self-Sufficiency4062% ev.
Admin Boringness41100% ev.
Durability5893% ev.
Property Autonomy41100% ev.
Carry Cost32100% ev.

Evidence strength: 90%. This reports direct-source completeness and fallback use; it is separate from the score and is not a confidence interval. How it works →

$858kTypical home
0.3%Property tax
$29,887Land / acre
3.7% of yrsSevere drought
0 / yr (+0)Mid-century 100°F days
1.04×Wildfire change factor
80%Forward climate coverage
$2,068Home insurance / yr
2.5% / yrInsurance growth
0.28%Nonrenewal rate
county median (2+ published ZIPs)Insurance basis
54,156People within 30 min
1,019,302People within 2 hr
707,549Radius comparison (15 mi)
1,647.3People / sq mi
41.3%Land at 15% slope or less
13.1%Septic soil without severe limits
48,343 acWorkable land screen

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Answers from the rulebook for Honolulu County

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

Honolulu County rules

  • Building permitRequired

    Construction work covered by the City and County of Honolulu building code on Oahu.

    • The requirement applies to work covered by the building code as provided in ROH Chapter 18.
    • Construction may proceed after the required building permit is obtained.
    • Certain work may be exempt under ROH Chapter 18; the cited provision does not enumerate those exemptions.
    “A building permit is required to perform work covered by this code as provided in ROH Chapter 18.”
  • InspectionsRequired

    All construction or work in Honolulu for which a building permit is required.

    • The work must remain accessible and exposed for inspection purposes.
    • The person doing permitted work must notify the building official when the work is ready for inspection.
    • The building official may require inspection requests to be filed at least one working day before the requested inspection.
    • A final inspection is required after all construction is completed and before final occupancy.
    • Lath and gypsum board inspection is required for fire-resistive construction, with an exception for lath and gypsum board installed in Group U occupancies.
    • Building permit-related inspections are conducted by the DPP Building Division, except inspections by the Honolulu Fire Department.

    minimum inspection-request notice: >= 1 working day (The building official may require this notice.)

    “All construction or work for which a permit is required shall be subject to inspection by the building official.”
  • Certificate of occupancyRequired

    Use or occupancy of a building or structure, and changes in the existing occupancy classification, under the Honolulu residential building-code provisions.

    • No building or structure may be used or occupied, and no change in existing occupancy classification may be made, until the building official issues a certificate of occupancy.
    • The certificate is issued after inspection and a finding that there are no violations of the code or other laws enforced by the department.
    • A temporary certificate may be issued before completion of the entire permitted work only if the occupied portion is safe and complies with the code; the building official sets its validity period.
    • The certificate may be suspended or revoked if issued in error, based on incorrect information, or if the structure violates an ordinance, regulation, or code provision.
    “No building or structure shall be used or occupied, and no change in the existing occupancy classification of a building or structure or portion thereof shall be made until the building official has issued a certificate of occupancy therefore as provided herein.”
  • County-wide zoningPresent

    Zoning districts, precincts, permitted uses and structures, and zone-change procedures throughout the City and County of Honolulu.

    • Specific uses remain subject to the applicable zoning district, precinct, development standards, and permit procedures.
    • The official source describes Chapter 21 as the Revised Ordinances of Honolulu Land Use Ordinance.
    “Chapter 21 of the Revised Ordinances of Honolulu, better known as the Land Use Ordinance (LUO), provides a list of zoning districts and precincts, the permitted uses and structures for each district and precinct, and the procedures under which applications for proposed zone changes are processed.”
  • Local zoningPresent

    Local zoning administered by the City and County of Honolulu through the Land Use Permits Division across Honolulu County.

    • The Land Use Permits Division administers Chapter 21, the Land Use Ordinance.
    • Specific zoning permits, districts, precincts, and development standards may impose additional requirements.
    “Administers Chapters 21, 25, and 26 of the Revised Ordinances of Honolulu, respectively the Land Use Ordinance, Special Management Areas Ordinance, and the Shoreline Setbacks Ordinance.”
  • Zoning districtsPublished

    Zoning districts and precincts under Chapter 21 of the Revised Ordinances of Honolulu, administered by the City and County of Honolulu.

    • The Land Use Ordinance also identifies permitted uses and structures for each district and precinct.
    • Zone changes are amendments to the zoning ordinance adopted by the City Council to establish the affected zoning map.
    • A large-area landowner may alternatively seek a minor adjustment through a Zoning District Boundary Adjustment.
    “Chapter 21 of the Revised Ordinances of Honolulu, better known as the Land Use Ordinance (LUO), provides a list of zoning districts and precincts, the permitted uses and structures for each district and precinct, and the procedures under which applications for proposed zone changes are processed.”
  • Mandatory utility hookupConditional

    Projects in Honolulu County involving connection to the City and County of Honolulu municipal sewer system, particularly new sewer connections from unsewered lots and projects in areas with City-maintained or City-owned sewers.

    • A Sewer Capacity Analysis is required for projects that may increase sewage flow to the municipal sewer system.
    • The analysis form must be submitted for a new sewer connection from an unsewered lot, among other listed project types.
    • The City and County of Honolulu Wastewater Branch reviews sewer connection applications and projects in areas with sewers maintained or owned by the City and County.
    • Projects served by cesspools or septic tanks that are not connected to the municipal sewer system require approval by the State Department of Health.
    “A Sewer Capacity Analysis is required for projects that may increase sewage flow to the municipal sewer system.”
  • Short-term rentalsLimited

    Short-term rentals of less than 30 days in the City and County of Honolulu.

    • Short-term rentals are permitted only in resort-zoned areas and other STR-eligible areas shown by the City.
    • Each unit rented for less than 30 days must be registered.
    • Existing NUC holders and hotel and timeshare units are exceptions to the new registration system.
    • A written zoning verification request may be submitted if eligibility is uncertain; the stated cost is $300.
    • Registration is effective for one year and must be renewed annually before expiration.

    rental period: < 30 days (Hotel and timeshare units and existing NUC holders are excepted from the new registration system.) · written zoning verification fee: 300 USD

    “STRs are only permitted in resort-zoned areas, and as shown in Ordinance 25-52. Any owner or operator interested in renting out a unit within the STR-eligible areas for less than 30-days must register each unit to be rented for less than 30 days.”
  • Permit feesPublished (with conditions)

    Building permit fees administered by the City and County of Honolulu Department of Planning and Permitting.

    • Fees are based on the project's fair-market labor and materials value.
    • A plan review fee applies when plans are required under Revised Ordinances of Honolulu Chapter 18.
    • Fees may be exempt depending on the scope of work under Chapter 18.
    • Separate building permits and fees are required for each structure.

    fee basis: project value based on fair market labor and materials

    “Permit fees are based on project value (fair market labor and materials). To calculate the fees, enter your project value into the Estimated Fee Calculator.”
  • Permit processPublished (with conditions)

    City and County of Honolulu building permit applications and electronic plan review.

    • Applicants may submit an Instant Online Permit or a Building Permit depending on project type.
    • Instant Online Permits are generally for single-family dwellings and are unavailable when the property is in a flood zone or has an advisory or violation.
    • For a Building Permit, the applicant submits an Internet Building Permit Application, receives an IBP number, and submits plans through the One-Stop Permit Center or Electronic Plan Review.
    • OTR-60 is optional and limited to eligible detached single-family and two-family residential projects submitted through ePlans, including projects not located in a flood zone.
    • A separate building permit is generally required for each building or structure.

    application channel: Internet Building Permit Application and ePlans or Instant Online Permit when eligible

    “Yes. Depending on the type of project you are working on, you may submit for an Instant Online Permit or a Building Permit. To submit electronic plans, when you apply for a building permit select the Electronic Plan Review option.”

Hawaii rules that apply here

  • Owner-builder exemptionAvailable (with conditions)

    Owners or lessees in Honolulu County who build or improve residential or farm buildings or structures for their own use or for use by their grandparents, parents, siblings, or children, subject to Hawaii's owner-builder exemption requirements.

    • The owner or lessee must register for the exemption under HRS §444-9.1.
    • The exemption does not apply to electrical or plumbing work that must be performed by licensed persons or entities unless the owner or lessee is licensed under Chapter 448E.
    • The owner or lessee must supervise construction, hire appropriately licensed subcontractors for work requiring a license, ensure electrical and plumbing work is performed by appropriately licensed persons or entities, handle required employment taxes and workers' compensation for unlicensed workers treated as employees, and comply with applicable laws, ordinances, building codes, and zoning regulations.
    • Until completion, the owner or lessee must make the building permit application, issued building permit, contracts, and proof of payment available for immediate inspection upon department request.
    • After completion, those records must be retained for three years and made available within seven business days upon request.
    • Sale, lease, or offer for sale or lease within one year after completion is prima facie evidence that the project was undertaken for sale or lease, except for residential properties sold or leased to employees, work under an approved building permit with estimated valuation below $10,000, or an eligible unforeseen hardship determined by the board.
    • An unforeseen-hardship application must be submitted before sale, lease, or offer, with supporting documentation; the board must communicate its determination within 90 days of receiving a completed application.
    • For this statute, completion means the date of final inspection approval by the county.
    • The exemption does not apply to agricultural buildings, structures, or appurtenances that do not require a building permit or are exempt from the building code.

    record-retention period after completion: 3 years · inspection-record response period after completion: 7 business days · presumed sale-or-lease period: 1 year after completion (Employee sale or lease; approved permit with estimated valuation below $10,000; eligible unforeseen hardship.) · approved-permit valuation exception: < 10000 USD (Construction or improvements performed pursuant to an approved building permit.) · board hardship determination period: 90 days (Measured from receipt of a completed application.)

    “This chapter shall not apply to owners or lessees of property who build or improve residential or farm buildings or structures on property for their own use, or for use by their grandparents, parents, siblings, or children, and who do not offer the buildings or structures for sale or lease; provided that:”
  • Building code adoptedAdopted

    The Hawaii state building codes applicable to all construction statewide, including residential construction in unincorporated areas.

    • The codes are based on the state fire code, Uniform Plumbing Code, International Building Code, International Residential Code, International Energy Conservation Code, National Electrical Code, specified Hawaii design standards, and nationally published code provisions including residential, hurricane-resistant, flood, tsunami, existing-building, and onsite-sewage-disposal provisions.
    • County governing bodies must amend, adopt, and update the Hawaii state building codes for their respective jurisdictions and incorporate the standards listed in HRS §107-25 into county building-code ordinances no later than two years after adoption of the Hawaii state building codes.
    • If a county does not amend the Hawaii state building codes within the two-year period, the Hawaii state building codes become applicable as an interim county building code.

    county adoption deadline: 2 years after adoption of Hawaii state building codes

    “There is established the Hawaii state building codes applicable to all construction in the State of Hawaii.”
  • Minimum lot sizeSpecified

    Agricultural districts statewide; the exact agricultural-district minimum is determined by each county through zoning ordinance, subdivision ordinance, or other lawful means, subject to the state one-acre floor and statutory exceptions.

    • Each county determines the agricultural-district minimum lot size by zoning ordinance, subdivision ordinance, or other lawful means.
    • The minimum lot size for any agricultural use shall not be less than one acre, except as provided in §205-5(b).
    • A county may allow smaller lots for consolidation and resubdivision when it finds unreasonable economic hardship cannot otherwise be prevented or land utilization is improved, but the consolidation and resubdivision may not increase the number of lots over the number existing before consolidation.
    • A lot equal to or exceeding one acre may not be reduced below one acre through the consolidation and resubdivision action.
    • A county may also allow smaller lots for plantation community subdivisions, public, private, and quasi-public utility purposes, and lots resulting from subdivision of abandoned roadways and railroad easements.

    minimum lot size for agricultural use: >= 1 acre (except as provided in section 205-5(b)) · lot-count change in consolidation and resubdivision: 0 additional lots (consolidation and resubdivision may not result in an increase in the number of lots over the number existing prior to consolidation)

    “determined by each county [...] shall not be less than one acre”
    3 more reviewed findings on this topic
    • Specified — Low-density residential uses in Hawaii rural districts.
      “minimum lot size for any low density residential use shall be one-half acre”
    • Specified — Lots used for agricultural purposes in Hawaii agricultural districts.
      “The minimum lot size in agricultural districts shall be determined by each county by zoning ordinance, subdivision ordinance, or other lawful means”
    • Specified — Residential lots in Hawaii rural land-use districts.
      “Rural districts shall include activities or uses as characterized by low density residential lots of not more than one dwelling house per one-half acre”
  • Living in an RVLimited

    Use of an RV or other vehicle for human habitation while parked on a roadway, street, highway, or other public property between 6:00 p.m. and 6:00 a.m., and use while parked on private property without authorization for both parking and habitation.

    • The prohibition applies between 6:00 p.m. and 6:00 a.m. on roadways, streets, highways, and other public property.
    • On private property, authorization of both the owner or occupant for parking the vehicle and its use for human habitation is required.
    • Human habitation includes use as a dwelling place, living abode, or sleeping place.
    • The prohibition does not apply in parks, camps, and other recreational areas when the use complies with applicable law and rules and regulations.
    • The prohibition does not apply under emergency conditions in the interest of vehicular safety.

    prohibited hours on public property: 6:00 p.m. to 6:00 a.m.

    “No person shall use any vehicle for purposes of human habitation [...] between the hours of 6:00 p.m. and 6:00 a.m.”
    One more reviewed finding on this topic
  • Camping on your landLimited

    Camping in Hawaii Forest Reserves administered by the Department of Land and Natural Resources, Division of Forestry and Wildlife.

    • A camping permit is required for all persons, groups, organizations, or associations wishing to camp within a Forest Reserve.
    • Camping is only allowed at official campsites.
    “All persons [...] wishing to camp within a Forest Reserve are required to obtain a camping permit. Camping is only allowed at official campsites.”
  • Accessory dwellingsAllowed (with conditions)

    Construction and residential use of accessory dwelling units on qualifying residentially zoned lots in Hawaii, subject to county ordinances and the statutory geographic and hazard exclusions.

    • Each county must adopt or amend accessory dwelling unit ordinances under HRS §46-4.8.
    • Except for the alternatives in subsections (c) and (d), county standards must allow at least two accessory dwelling units, or the reasonable equivalent, for residential use on all residentially zoned lots.
    • If a county uses the subsection (c) alternative, qualifying districts must be consistent with the county comprehensive general plan, reasonably distributed throughout the county's regional planning areas, and estimated to add development potential equivalent to half of the county's projected five-year demand stated in the 2019 Hawaii housing planning study.
    • The subsection (c)(2) alternative concerns districts within a reasonable walking distance of stations of a locally preferred alternative for a mass transit project and urban principal arterials situated within a primary urban area, urban core, or county equivalent identified by a county comprehensive general plan.
    • A county with a population of five hundred thousand or more must also address existing apartment or apartment mixed-use districts under subsection (d).
    • Accessory dwelling units remain subject to all development standards adopted by the respective county.
    • A county may deny permits when utility infrastructure is insufficient; after December 31, 2026, if a county has not adopted or amended zoning ordinances under this section, it may not deny an application for up to two accessory dwelling units solely because of the maximum number of housing units, but may deny based on infrastructure, design, or development standards.
    • The section does not apply outside the state urban district, to county powers within special management areas, or to urban-district areas the county deems at high risk of flooding, lava, or fire based on the most current federal or state data and maps.
    • The statutory definition of residentially zoned lot excludes county districts intended for rural, low density residential development and open space preservation.
    • The section does not create vested rights and does not preempt county authority to accept, review, approve, or deny permit applications.

    minimum accessory dwelling units or reasonable equivalent: >= 2 units per qualifying residentially zoned lot (Subject to HRS §46-4.8(c)-(d) alternatives and exclusions.) · county zoning ordinance deadline: 2026-12-31 (If the county has not adopted or amended zoning ordinances under HRS §46-4.8.)

    “Except as provided in subsections (c) and (d), each county shall adopt or amend ordinances [...] at least two accessory dwelling units”
    One more reviewed finding on this topic
    • Allowed (with conditions) — Accessory dwelling units for residential use on residentially zoned lots within Hawaii urban districts, subject to county implementation and applicable county development standards.
      “each county shall adopt or amend ordinances defining reasonable standards that allow for the construction of at least two accessory dwelling units”
  • Who permits septicState (with conditions)

    Individual wastewater systems, including septic systems, serving properties in Honolulu County that are not serviced by a sewer system.

    • The Hawaii Department of Health Wastewater Branch administers statewide engineering functions for individual wastewater systems.
    • The Wastewater Branch states that its jurisdiction does not extend to properties serviced by sewer; wastewater issues for those properties are directed to the relevant county department or private sewer provider.
    “The Wastewater Branch administers the statewide engineering functions relating to water pollution control, municipal and private wastewater treatment works, individual wastewater systems and the Clean Water State Revolving fund.”
    One more reviewed finding on this topic
    • State — Statewide administration of individual wastewater systems, including septic systems, in Hawaii.
      “The Wastewater Branch administers the statewide engineering functions relating to water pollution control, municipal and private wastewater treatment works, individual wastewater systems and the Clean Water State Revolving fund.”
  • Septic permitRequired

    New or modified individual wastewater systems, including septic systems, in Honolulu County.

    • A licensed engineer must perform a percolation test, survey the property, determine wastewater requirements, and submit plans to the Wastewater Branch for review and approval.
    • Every applicant must pay a filing fee: $100 for a new individual wastewater system, treatment unit, or disposal system; $25 for an addition or modification to an approved or existing system.
    • No person may use an individual wastewater system until authorized in writing by the director.
    • No cesspool may be used as the wastewater system by any new building, and no new cesspool may be constructed after the rule’s effective date unless approved for construction before that effective date.

    new IWS, treatment unit, or disposal system filing fee: 100 USD · addition or modification filing fee: 25 USD

    “The application to construct a new individual wastewater system or to modify an existing individual wastewater system shall be made by the applicant on forms furnished by the director.”
    One more reviewed finding on this topic
  • Septic inspectionRequired

    Construction and approval for use of individual wastewater systems, including septic systems, in Honolulu County.

    • The owner must resolve discrepancies recorded from inspections before written approval to use is issued.
    • The engineer must furnish a final inspection report within 30 days after construction completion, including certification of construction according to approved plans and an as-built plan.
    • The director may inspect the system or site at any time before approval and may require advance notice of the engineer’s inspection.

    final inspection report deadline: 30 days after construction completion

    “The engineer furnishes a final inspection report to the director within thirty days after the completion of the construction”
    One more reviewed finding on this topic
  • Well permitRequired

    Construction, modification, or sealing of water, production, exploratory, and monitor wells statewide.

    • The Commission on Water Resource Management administers the well construction permit requirement for water, production, exploratory, and monitor wells.
    • Injection wells instead require a State Department of Health permit.
    • Geothermal wells require a Department of Land and Natural Resources, Engineering Division permit.
    • Temporary test borings and test-boring sealings do not require a permit; permanent test borings for long-term monitoring are treated as monitoring wells and require a Commission permit.
    • Well construction, modification, or sealing work must be performed by a C-57 licensed well driller; pump installation work may be performed by a C-57, C-57a, or A-licensed contractor.

    well driller license: C-57 · pump installer license: C-57, C-57a, or A

    “In the State of Hawaii, work on water wells, production wells, exploratory wells and monitor wells requires a well construction permit from the Commission; work on injection wells requires a permit from the State Department of Health; and work on geothermal wells requires a permit from the Department of Land and Natural Resources, Engineering Division.”
    One more reviewed finding on this topic
  • Agricultural exemptionConditional

    Agricultural lands subdivided and leased for agricultural uses or activities permitted in HRS §205-4.5(a).

    • The principal use of the leased land must be agriculture.
    • No permanent or temporary dwellings or farm dwellings, including trailers and campers, may be constructed on the leased area.
    • Storage sheds, equipment sheds, and other structures appropriate to the agricultural activity carried on within the lot are not prohibited by the dwelling restriction.
    • Violations of the no-dwelling paragraph are subject to county enforcement authority and fines under §§46-4, 205-12, and 205-13.
    • The lease term must be at least as long as the greater of the county's minimum real-property-tax agricultural-dedication period or five years.
    • Lots created and leased under this section are legal lots of record for mortgage-lending purposes and are exempt from county subdivision standards.

    minimum lease term: greater of county minimum real property tax agricultural dedication period or five years · dwelling construction on leased area: false (storage sheds, equipment sheds, and other structures appropriate to the agricultural activity are not prohibited)

    “Lots created and leased pursuant to this section shall be legal lots of record for mortgage lending purposes and shall be exempt from county subdivision standards.”
  • Subdividing landLimited

    Subdivision and leasing of agricultural lands for permitted agricultural uses under HRS §205-4.5(f).

    • The principal use of the leased land must be agriculture.
    • No permanent or temporary dwellings or farm dwellings, including trailers and campers, may be constructed on the leased area.
    • Storage sheds, equipment sheds, and other structures appropriate to the agricultural activity are not prohibited by this subsection.
    • Violations are subject to county enforcement authority and fines under HRS §§46-4, 205-12, and 205-13.
    • The lease term must be at least the greater of the county minimum real-property-tax agricultural-dedication period or five years.
    • Lots created and leased under this section are legal lots of record for mortgage lending purposes and are exempt from county subdivision standards.

    minimum lease term: >= 5 years (The term must instead be at least the greater of five years or the county agricultural-dedication period.)

    “Lots created and leased pursuant to this section shall be legal lots of record for mortgage lending purposes and shall be exempt from county subdivision standards.”
    2 more reviewed findings on this topic
  • Driveway accessRequired

    Routine construction involving residential driveways within the State highway right-of-way in Hawaii

    • The rule applies to ground disturbance within the State highway right-of-way.
    • The applicant must obtain clearance signatures from various utility companies.
    • Two sets of scaled construction plans are required, including a location map, existing highway facilities, and a traffic control plan.
    • Insurance is required.
    • The fee schedule varies and the minimum fee is $10.00.
    • A bond is required with a minimum of $1,000.00.
    • Three sets of plans, preferably 11 x 17, are required.
    • The DOT Best Management Practices form must be completed for review by the DOT Environmental section.
    • A Lane Closure Form must be completed two weeks in advance if proposed work involves lane or shoulder closures.
    • In most cases, review and processing occur within one week, depending on the work and BMP form complexity.

    minimum fee: >= 10 USD (Fee schedule varies.) · minimum bond: >= 1000 USD · lane closure form lead time: 2 weeks (Required if proposed work involves lane or shoulder closures.)

    “Routine construction projects within the State highway right-of-way consisting of ground disturbance of any kind: a. Residential driveways;”
  • Building in a floodplainRequired

    Agricultural buildings, structures, appurtenances, and related development seeking the HRS §46-88 permit and code exemptions statewide in Hawaii

    • The exemption applies to nonresidential agricultural buildings, structures, and appurtenances and does not apply to dwellings or lodging units.
    • The property must be used primarily for agricultural or aquacultural operations and generally must be at least two contiguous acres, or at least one contiguous acre if located in a nonresidential agricultural or aquacultural park.
    • The owner or occupier must provide written notice to the appropriate county agency stating the size, type, and location of the proposed development.
    • No work may commence until the county agency determines that a building permit is not required for compliance with county, state, or federal floodplain management requirements under National Flood Insurance Program requirements.
    • The appropriate county agency must certify the development within thirty calendar days after receiving the written notice.
    • A final as-built written notice must be provided to the county agency within thirty calendar days of completion, occupancy, or use; failure may void the exemption at the county agency's discretion.
    • Electrical and plumbing permits are separately required before those systems are connected.
    • Wastewater disposal must comply with chapter 342D.
    • The exemption does not apply to development in the state land use urban district.
    • HRS §46-88 does not exempt new or existing agricultural development from county, state, or federal floodplain management requirements under National Flood Insurance Program requirements.
    • Failure to comply results in penalties consistent with county building department provisions.

    minimum contiguous acreage: >= 2 acres (One or more contiguous acres if located in a nonresidential agricultural or aquacultural park.) · county certification deadline: 30 calendar days (Measured from receipt of the owner's or occupier's written notice.) · final as-built notice deadline: 30 calendar days (Measured from completion, occupancy, or use.)

    “No work shall commence until the county agency has determined that a building permit for the proposed building”
  • county zoning authorityGeneral

    Hawaii counties' zoning authority over lands outside forest reserve boundaries, including unincorporated county areas.

    • The authority applies to lands not contained within forest reserve boundaries established on January 31, 1957, or as subsequently amended.
    • Zoning must be accomplished within the framework of a long-range, comprehensive general plan.
    • The zoning power must be exercised by ordinance.
    • The statute identifies authority over agricultural, forestry, industrial, trade, business, residential, watercourse, special-restriction, building-location, height, bulk, setback, density, lot-coverage, open-space, lot-size, and use-duration matters.
    • The powers are to be liberally construed in favor of the county, subject to forest and water reserve limitations and the exceptions in HRS §46-4(c), (d), (g), and §46-4.8.
    “The zoning power granted in this section shall be exercised by ordinance, which may relate to:”
    One more reviewed finding on this topic
    • General — Hawaii counties adopting and enforcing zoning ordinances for lands within county jurisdiction, including unincorporated areas, subject to statutory exclusions and planning requirements.
      “The zoning power granted in this section shall be exercised by ordinance, which may relate to:”

Inside cities and towns in Honolulu County

Municipal rules found while researching the county. They apply inside that city or town, not to unincorporated land.

  • Minimum lot sizeDistrict specific (with conditions)

    Residential and other zoning-lot uses governed by the City and County of Honolulu Land Use Ordinance on Oahu.

    • The applicable minimum lot size depends on the zoning district and use.
    • The DPP FAQ states that an Ohana dwelling requires the legal lot of record to conform to the minimum lot size and dimensions for the district.
    • Other applicable Land Use Ordinance standards and infrastructure approvals may also apply.

    minimum lot size: district-specific (Depends on zoning district and use)

    “Ohana dwellings may be built in the agricultural, country and residential zoning districts (except in the R-3.5 Residential District), if the legal lot of record conforms to the minimum lot size and dimensions for the district.”
  • SetbacksSpecified

    Residential dwellings on Oahu under the City and County of Honolulu Land Use Ordinance.

    • The general guideline is 10 feet from the front property line and 5 feet from side and rear property lines.
    • Side and rear yards must be larger when floor area ratio exceeds 0.6.
    • Article 3 of the Land Use Ordinance contains the applicable district-specific development standards.

    front setback: 10 feet (General residential dwelling guideline; district-specific standards may apply) · side setback: 5 feet (General residential dwelling guideline; larger yards may apply when FAR exceeds 0.6) · rear setback: 5 feet (General residential dwelling guideline; larger yards may apply when FAR exceeds 0.6)

    “In general, dwellings must be set back 10 feet from the front property line and 5 feet from the side and rear property lines. However, side and rear yards must be larger for floor area ratios exceeding 0.6. Please refer to Article 3 of the Land Use Ordinance for development standards.”
  • Lot coverageSpecified

    Residential dwelling zoning lots on Oahu under the City and County of Honolulu Land Use Ordinance.

    • The cited requirement concerns total impervious surface area, including paved areas and driveways, rather than only building footprint.
    • The DPP FAQ identifies rooftops, walkways, patios, driveways, parking lots, impervious concrete and asphalt, and other continuous watertight pavement or covering as examples.
    • The ordinance may contain additional district-specific development standards and nonconforming rules.

    maximum impervious surface area: <= 75 percent of zoning lot area (Applies to dwelling units constructed pursuant to building permits applied for after May 1, 2019, according to the cited ordinance text referenced by DPP)

    “The total paved area including driveways shall not cover more than 75% of the lot. Impervious surfaces areas include, but are not limited to, rooftops, walkways, patios, driveways, parking lots, storage areas, impervious concrete and asphalt, and any other continuous watertight pavement or covering.”
  • Building heightDistrict specific (with conditions)

    Residential rebuilding and new residential construction on Oahu under the City and County of Honolulu Land Use Ordinance.

    • Height requirements depend on zoning and the applicable development standards.
    • The DPP FAQ states that a legally permitted house may be rebuilt only if all Land Use Ordinance standards are met, including height.
    • District-specific standards are found in Article 3 of the Land Use Ordinance.

    building height limit: district-specific (Depends on zoning district and applicable development standards)

    “General development standards are contained in Article 4 of the LUO, and district-specific development standards are found in Article 3.”
  • Agricultural exemptionAvailable (with conditions)

    Agricultural buildings or structures on farms and ranches in Honolulu County/Oahu that satisfy Hawaii Revised Statutes section 46-88 and are declared with the City and County of Honolulu.

    • The structure must be built in accordance with HRS 46-88.
    • The structure must be declared with the City and County of Honolulu.
    • If an existing declared exempt structure is altered in a way that no longer meets HRS 46-88, a building permit is required.
    • Exempt structures may not have plumbing or electrical work.
    • The submission requires a Declaration of Compliance with HRS 46-88, Certification of HRS 46-88 Exemption #12 as required, and a plot plan showing location, property lines, other structures, setbacks, and dimensions.

    building permit exemption: true (Only for agricultural buildings or structures complying with HRS 46-88) · declaration: required (Declaration with the City and County of Honolulu is required)

    “Agricultural building or structures built in accordance with Hawaii Revised Statues 46-88 are exempt from building permits. However, you must declare the structure with the City and County of Honolulu.”
  • Subdividing landRegulated (with conditions)

    Subdivision and consolidation of land on Oahu administered by the City and County of Honolulu Department of Planning and Permitting.

    • DPP processes subdivision reviews and inspections.
    • Subdivision applications must comply with applicable subdivision rules and standards.
    • The cited street standards contain transition rules for applications submitted before their effective date, roadway master plans, and extensions or expansions of existing roadways.
    • The DPP may modify street standards under the Subdivision Rules and Regulations.

    subdivision review: required (Specific exceptions and transition rules may apply under the subdivision regulations)

    “The Site Development Division is responsible for the review, approval, and inspection of new subdivisions and their associated improvements;”

Still unanswered

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

  • Minimum dwelling size — Minimum dwelling size for residential dwellings on Oahu administered by the City and County of Honolulu.
  • Tiny homes — Occupancy of tiny homes in Honolulu County.
  • Manufactured homes — Occupancy of manufactured homes in Honolulu County.

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.

Water rights & wells in Honolulu County

Whether a new home can legally get its own water here — the sub-state groundwater regime, from Hawaii’s water agency.

Managed area

Groundwater is actively managed here, but a small household well is generally still available.

Household wellPermit required (issued by right)

No well may be drilled without CWRM permits (HAR 13-168), including inside a designated Ground Water Management Area. But individual domestic use and rain-catchment are EXEMPT from the Water Use Permit even inside a designated area (HRS 174C-48) — a household faces construction permitting, not appropriation permitting.

Limit: CWRM Well Construction + Pump Installation Permit required statewide before drilling

Hawaii CWRM — Well Construction & Pump Installation; HRS 174C-48 ↗
  • Oahu Ground Water Management Area

    All of Oahu is a CWRM-designated Ground Water Management Area; new non-domestic sources need a Water Use Permit and the Pearl Harbor/Honolulu sectors are heavily allocated, but individual domestic users and rain-catchment are exempt (HRS 174C-48). A well-construction permit is still required.

    Hawaii CWRM — Water Management Areas ↗

Regulated-riparian state (large uses permitted). Groundwater rules change and basin boundaries follow the aquifer, not the county line — confirm current well and appropriation rules with the Hawaii state water agency before you buy or drill.Groundwater governance as of Jul 2026, cited to each administering agency.

Living off-grid in Honolulu County, Hawaii

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

Honolulu County scores 48/100 on the Bolthole Index, a solid county profile. Watch-outs: higher long-term carry cost and its water supply.

Do you need a building permit in Honolulu County, Hawaii?

Honolulu County generally requires a residential building permit, and it enforces county zoning. Onsite septic is permitted by Hawaii State Department of Health - Wastewater Branch. 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 Honolulu County?

Living in an RV on your own land in Honolulu County is limited to specific cases: Statewide rule. Use of an RV or other vehicle for human habitation while parked on a roadway, street, highway, or other public property between 6:00 p.m. and 6:00 a.m., and use while parked on private property without authorization for both parking and habitation. The prohibition applies between 6:00 p.m. and 6:00 a.m. on roadways, streets, highways, and other public property. On private property, authorization of both the owner or occupant for parking the vehicle and its use for human habitation is required. Confirm with the county before relying on it.

How much does land cost in Honolulu County, Hawaii?

Land in Honolulu County runs about $29,887 per acre, based on the latest county data.

What is the water situation in Honolulu County?

Water data for Honolulu County is limited. On water rights, Honolulu County lies in the Oahu Ground Water Management Area — All of Oahu is a CWRM-designated Ground Water Management Area; new non-domestic sources need a Water Use Permit and the Pearl Harbor/Honolulu sectors are heavily allocated, but individual domestic users and rain-catchment are exempt (HRS 174C-48). A well-construction permit is still required..

How remote is Honolulu County?

A representative private-land location has about 54,156 people within a 30-minute drive and 1,019,302 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.

Off-grid gear

Going off-grid in Honolulu County means bringing your own water and power. The kit we’d start with:

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How Honolulu compares in Hawaii

Compare side-by-side →See all 5 Hawaii counties ranked →