Property tax on Kauai runs from $2.59 per $1,000 of assessed value for owner-occupied homes up to $12.20 for the highest-value vacation rentals, with bills issued in two installments due August 20 and February 20. The county sets your assessment as of October 1 for the tax year that starts the following July 1, and most of what you can do to reduce the bill, whether that is claiming the home exemption or appealing a valuation, is tied to a hard annual deadline.
Current Rates by Classification
Kauai sorts every parcel into one of nine classifications, each with its own rate per $1,000 of net assessed value. Several categories now use tiers that increase as taxable value crosses set thresholds. The rates below apply to Fiscal Year 2025–2026, running July 1, 2025 through June 30, 2026.1County of Kauai. Tax Rates – Kauai County, HI
- Owner-Occupied: $2.59
- Owner-Occupied Mixed-Use: $5.05
- Non-Owner-Occupied Residential: $5.45 on the first $1,300,000; $6.05 from $1,300,001 to $2,000,000; $9.40 above $2,000,000
- Vacation Rental: $11.30 on the first $1,000,000; $11.75 from $1,000,001 to $2,500,000; $12.20 above $2,500,000
- Hotel and Resort: $11.75
- Commercial: $8.10
- Industrial: $8.10
- Agricultural: $6.75
- Conservation: $6.75
Tiered categories do not apply the top rate to the whole value. A $3 million vacation rental pays $11.30 on the first $1 million, $11.75 on the next $1.5 million, and $12.20 on the remaining $500,000. The county council adjusts rates each year, so confirm the current schedule before you budget.
The Home Exemption for Owner-Occupants
The home exemption is the single largest tax break available to Kauai residents. It subtracts a flat amount from your assessed value before the rate is applied, and the amount scales with age:2County of Kauai. Exemption/Tax Relief Information – Kauai County, HI
- Under 60: $220,000
- Age 60 to 69: $240,000
- Age 70 or older: $260,000
To qualify you must occupy the property as your principal home for more than 270 days during the calendar year, file a full-year Hawaii resident income tax return, hold a Hawaii driver’s license or state ID, and not claim a primary residence exemption anywhere else.3County of Kaua’i. Real Property Tax Relief and Exemptions Deadline Sept. 30 Only one exemption is allowed per owner. Your age on the assessment date determines your bracket, so a birthday that pushes you past 60 or 70 before October 1 moves you up automatically.
The math is straightforward. A home assessed at $900,000, owned by someone 65 years old, has $240,000 subtracted first, leaving $660,000 in taxable value. At the owner-occupied rate of $2.59 per $1,000, the annual tax works out to roughly $1,709, compared with $2,331 without the exemption. The gap widens each year as assessments rise.
Other Relief Programs
Kauai County Code Chapter 5A provides additional relief for people with impaired sight or hearing, residents with disabilities, and low-income property owners. Amounts and eligibility vary, and the Real Property Assessment Division can confirm which program fits your situation.
If you rent out a dwelling under a written lease of a year or longer at rents at or below the county’s affordable rental limit, you can apply for the Long-Term Affordable Rental program.4eCode360. Kauai County Code Chapter 5A – Article 11A, Limitation of Taxes The ceiling is tied to the midpoint of maximum rental limits using 80 to 100 percent of the Kauai median household income, published annually by the Kauai County Housing Agency. Each unit needs its own application, and each application needs a current signed lease showing landlord and tenant names, the address, bedroom and bathroom count, lease dates, monthly rent, utility responsibility, and both signatures.5County of Kaua’i. 2027 Long-Term Affordable Tenant Occupied Rental Program If a lease ends on or before October 31 of the current year, submit a new lease by November 15 to keep the relief in place.
Deadlines That Matter
Three dates drive the Kauai property tax year.
September 30 is the deadline for all tax relief and exemption applications.3County of Kaua’i. Real Property Tax Relief and Exemptions Deadline Sept. 30 Miss it and you lose the exemption for the entire following fiscal year, with no path to claim it retroactively. The deed or other document showing you acquired the property must also be recorded at the Bureau of Conveyances by that same date. You will need your Tax Map Key (TMK) number, which appears on your assessment notice, along with the ID and residency documentation listed above. Forms are available at the Real Property Assessments office at 4444 Rice Street, Suite A-454, in Lihue, or online, and some can be submitted through the county’s electronic portal.
August 20 and February 20 are the two payment installments.6County of Kauai. Billing and Collections Section You can mail a check to the Director of Finance in Lihue, pay in person, or use the online portal at kauairpt.ehawaii.gov, where you will need the 15-digit TMK number printed on your bill.7State of Hawaii. Kauai Real Property Tax Payments If your mortgage servicer collects taxes through escrow, those payments go out on the same schedule.
December 31 is the appeal deadline, covered below.
Penalties and Liens
Missing either installment triggers a one-time penalty of up to 10 percent of the delinquent amount, with interest then accruing at 1 percent per month starting the first calendar month after the missed date.6County of Kauai. Billing and Collections Section8County of Kauai. A Bill for an Ordinance Amending Chapter 5A Both become part of the tax itself and must be paid in full to clear the balance. On a $5,000 installment, that is up to $500 on day one plus $50 every month after. Within a year, a $5,000 bill can grow past $6,100.
Every unpaid property tax automatically becomes a lien on the property as of July 1 of the tax year, and the lien stays active for six years.9eCode360. Kauai County Code Chapter 5A – Article 5, Liens, Foreclosures The county can record it with the Bureau of Conveyances, which blocks any sale or refinance until it is cleared. After three years of an outstanding lien, the Director of Finance can sell the property at public auction without filing a lawsuit, after publishing notice in a local newspaper for at least four consecutive weeks and mailing notice at least 45 days before the sale. The chain starts with one missed installment.
Appealing an Assessment
If you think the county overvalued your property, the first step is an appeal to the Board of Review. File a notice of appeal and pay a $75 deposit for each parcel being challenged by December 31.10eCode360. Kauai County Code Chapter 5A – Article 12, Appeals The deposit must be paid by the same deadline for the Board to have jurisdiction. If you succeed on at least 50 percent of the disputed valuation, the $75 is returned.
Strong appeals come with evidence: recent comparable sales, a professional appraisal, or documentation of defects that reduce value. An appraiser’s work must comply with the Uniform Standards of Professional Appraisal Practice (USPAP), which requires a complete work file supporting the valuation. Showing up with a general objection rarely moves the number.
If the Board rules against you, you can appeal to the Tax Appeal Court within 30 days of the decision, with a separate $100 deposit.11Hawaii State Judiciary. Rules of the Tax Appeal Court That is a formal judicial proceeding, and most property owners hire an attorney at that stage.
Federal Deduction Limits
Kauai property tax is deductible on your federal return as part of the state and local tax (SALT) deduction if you itemize. For the 2026 tax year, the SALT cap is $40,400 for most filing statuses and $20,200 for married filing separately.12Office of the Law Revision Counsel. 26 USC 164 – Taxes That cap covers all state and local taxes combined, so your Hawaii income tax and your Kauai property tax share the same limit. Anything above $40,400 produces no federal benefit. The cap rises 1 percent per year through 2029 and then drops back to $10,000 starting in 2030 under current law.