TMK guide · Land rules
TMK (Tax Map Key)
The number that names every parcel in Hawaiʻi.
A TMK, or Tax Map Key, is the number the State and Counties use for every parcel. It reads from the island down to the lot: division, zone, section, plat and parcel, and sometimes a four digit CPR unit.
The first digit is the County: 1 is Oʻahu, 2 is Maui County, 3 is Hawaiʻi Island and 4 is Kauaʻi. The TMK is on the tax bill, the deed and most listings.
A TMK names the parcel for tax and mapping. The legal boundary is in the recorded survey and deed.
What the law says, and who keeps it
What the ParcelSheet card shows
The TMK at the top of every sheet, with the lot drawn from the State parcel layer. The TMK checker reads any TMK.
Who to ask
The County Real Property Assessment office for the island.
See it on a real lot
- TMK 4-4-2-016-063, Kapaʻa, Kauaʻi
- TMK 1-3-3-025-016, Pālolo, Oʻahu
- TMK 3-2-4-024-162, Hilo, Hawaiʻi Island
Checked 2026-10-17. This page explains a term in plain words. It is not legal advice; the County or State office named above decides.
More land rules
- Special Management Area (SMA)
- State Land Use Districts
- FEMA flood zones and what X shaded means
- FIRM panels and LOMAs
- Tsunami evacuation and extreme tsunami zones
- Sea level rise exposure area
- Lava flow hazard zones 1 to 9
- CPR lots (condominium property regime)
- ʻOhana units and accessory dwelling units
- Shoreline setback
- Cesspool conversion (Act 125)
- Important Agricultural Lands (IAL)
- Conveyance tax
- Property tax classes by County