What will it really cost each month?
Mortgage, Hawaiʻi County property tax for your tax class, Hawaiian Electric's current Hawaiʻi Island rates, insurance, HOA and rural upkeep, in one monthly number. Change any input; nothing you type leaves your browser unless you ask me to email it.
How each number is figured
Principal & interest uses the standard fixed-rate formula on the loan amount (price minus down payment). It doesn't include mortgage insurance, which lenders usually add with less than 20% down, so ask your lender.
Property tax is the County's FY 2026–27 rate for the class you pick, applied per $1,000 of net taxable value, with the County's $200 minimum. In the Homeowner class, the home exemption comes off first. In the Residential class, higher rates apply only to the part of the value above $2 million, and only for properties with no exemption.
| Tax class | Rate |
|---|---|
| Residential, portion under $2 million | $11.10 |
| Residential, portion $2M–$4M (no exemption) | $14.50 |
| Residential, portion $4M and up (no exemption) | $17.00 |
| Homeowner (you live there and qualify for the Homeowner class) | $5.75 |
| Long Term Rental | $7.75 |
| Apartment | $11.70 |
| Agricultural and Native Forest | $9.35 |
| Conservation | $11.55 |
| Hotel/Resort | $11.55 |
| Commercial / Industrial | $10.70 |
| Owner's age | Base exemption |
|---|---|
| Under 60 | $50,000 |
| 60–64 | $85,000 |
| 65–69 | $90,000 |
| 70–74 | $105,000 |
| 75–79 | $110,000 |
| 80 or older | $125,000 |
The home exemption is for your principal home: you must live there more than 200 days a year and file a claim (RP Form 19-71). The Homeowner tax class has its own rules, including no rentals of 180 days or less, and comes with a 3% cap on yearly assessment increases. Check both with the Real Property Tax Office.
Electricity uses Hawaii Electric Light's residential Schedule R effective rates from October 1, 2026: a $13.14 monthly customer charge (single-phase), energy at $0.468411/kWh for the first 300 kWh, $0.506705/kWh for the next 700 and $0.519264/kWh above 1,000, a $28.56 minimum charge and a $1.33 Green Infrastructure Fee. For context, Hawaiian Electric reports that Hawaiʻi Island residential customers paid an average of 45.81¢ per kWh in 2025. Rates change monthly, and your real bill can differ.
Insurance, HOA, catchment and septic are your numbers. I leave them blank or at zero on purpose so the total never includes a guess.
An estimate for planning only. It's not a loan offer, tax bill or insurance quote, and not legal, tax or lending advice. Water, sewer, internet, maintenance and other costs aren't included. Figures checked October 23, 2026 against the sources below.
Sources · checked October 23, 2026
- County of Hawaiʻi Real Property Tax Office, Tax Rates (FY Jul 1, 2026 – Jun 30, 2027): hawaiipropertytax.com
- Hawaiʻi County Council, notice of real property tax rates adopted (Resolution 574-26), published Jun 14, 2026: statelegals.staradvertiser.com
- County of Hawaiʻi Real Property Tax Office, Homeowner Program (home exemption): hawaiipropertytax.com
- County of Hawaiʻi Real Property Tax Office, Home Exemption / Homeowner Program handout (Rev. 02/2024): hawaiipropertytax.com
- Hawaiian Electric, Effective Rate Summary effective Oct 1, 2026 (Hawaii Electric Light, Schedule R): hawaiianelectric.com
- Hawaiian Electric, Average Price of Electricity (2025 residential, Hawaiʻi Island): hawaiianelectric.com
- Freddie Mac Primary Mortgage Market Survey®, week of Oct 22, 2026: freddiemac.com
- Hawaiʻi REALTORS®, Statewide Statistics, September 2026 (Hawaiʻi County): hawaiirealtors.com
- Hawaii Property Insurance Association: hpiainfo.com