Ever see a string of numbers on a Honolulu listing and wonder what it actually means? You are looking at the Tax Map Key, or TMK, which is how Honolulu tracks every real property parcel for taxes, permits, and planning. If you are buying or selling, understanding the TMK helps you verify records quickly and avoid mix-ups. In this guide, you will learn what each part means, where to find a TMK, and how to use it during due diligence. Let’s dive in.
What a TMK number is
A Tax Map Key is the parcel identification number used throughout Hawaii to identify real property. Government offices use it to link a parcel across tax records, planning maps, permits, and other datasets. You will see TMKs on county tax systems, GIS maps, title reports, and many real estate documents.
Think of the TMK as the anchor that ties all your property research together. It helps you locate the exact parcel on official tax maps and reduces confusion when multiple properties share similar addresses.
Why TMKs matter in Honolulu
For buyers, the TMK is your fast path to facts. You can pull the county tax record, check zoning and permitted uses, review permit history, and look up hazard overlays. It is a practical starting point for property research.
For sellers, a verified TMK keeps your listing clean and accurate. You can confirm the parcel being offered, align your MLS details, gather permits and surveys, and resolve discrepancies before you launch to market.
A TMK is an administrative identifier. It is not a substitute for a legal description, a survey, or a title search. If you are making decisions about boundaries, encumbrances, or ownership, bring in the appropriate professionals.
TMK format at a glance
TMKs are written as groups of numbers separated by hyphens, for example: 1-2-34-056. Each group narrows from a broad map area to a specific parcel on the tax map. The way groups are displayed and how many digits are padded can vary between documents and databases.
Zone
The zone identifies a broad map area used by the county’s mapping system. It is the highest-level part of the TMK and helps you orient where the parcel sits in the county’s tax maps.
Section
The section points to a specific tax map sheet or neighborhood block within that zone. It narrows the search to a smaller set of map pages.
Plat
The plat locates the subdivision or map block where individual parcels are drawn. On official tax maps, the plat guides you to the page where lots are numbered.
Parcel
The parcel number is the unique identifier for the individual lot on that plat. This is the number you will use most often when searching county databases.
Extra digits and suffixes
Some systems append extra digits or suffixes. These can represent sub-parcels, condominium units, or internal database formatting. In condos or projects with multiple units, you may need an additional unit number or identifier beyond the base parcel number.
Where to find a property’s TMK
You can locate a TMK in several places. The key is to confirm it against official county records and the tax map.
Check common documents
- Property tax bill or county real property tax statement
- MLS listing and disclosure documents
- Deeds and related instruments recorded with the State Bureau of Conveyances
- Title company reports and preliminary title commitments
Use Honolulu county tools
- City and County of Honolulu Real Property Assessment Division for official tax records and TMK lookup by address or owner
- Honolulu county GIS and mapping viewers to see the parcel on a map and confirm the TMK visually
- Department of Planning and Permitting mapping and zoning tools that accept TMKs for research
Cross-check with maps
A simple way to confirm you have the right parcel is to pull it up on the county’s interactive map. Make sure the map boundaries, lot dimensions, and adjacent parcels match what you expect.
How buyers use a TMK
The TMK helps you move through due diligence efficiently and with fewer assumptions.
Buyer due diligence checklist
- Pull the county tax record to review assessed value and tax payment history.
- Open the county GIS viewer to confirm parcel boundaries, lot size, and adjacency.
- Check zoning and land-use rules with the Department of Planning and Permitting.
- Search permit history and active permits tied to the TMK to flag any unpermitted work.
- Review flood, tsunami, and other hazard overlays on county or state GIS layers for parcel-specific exposure.
- Provide the TMK to your title company and surveyor to align with the deed’s legal description.
- Look up exemptions or special tax assessments linked to the parcel.
How sellers use a TMK
A clean TMK is the backbone of an accurate listing and smoother disclosures.
Seller pre-listing checklist
- Confirm the TMK on your deed, tax bill, and MLS match exactly.
- Resolve tax delinquencies or special assessments tied to the TMK before going live.
- Gather permit history, surveys, and site maps that reference the TMK for buyer packets.
- Check for mistaken parcel assignments and work with the Real Property Assessment Division to correct issues early.
Limitations and pitfalls
- A TMK is administrative. It helps you find the parcel on maps, but it is not a legal boundary description and does not replace a survey.
- TMKs can change after subdivisions, consolidations, or remapping. Recently recorded changes may not appear in every database right away.
- A TMK alone does not show encumbrances like mortgages, liens, or easements. You will need a title search.
- Formatting differences, such as leading zeros or unit suffixes, can make a TMK look different between systems. Confirm against county records.
- Condominiums often require additional unit identifiers beyond the base parcel number for the overall lot.
Next steps to verify a TMK
- Use the TMK to retrieve the parcel on Honolulu’s GIS viewer and download the relevant tax map image.
- Pull the tax and assessment record from the Real Property Assessment Division to verify assessed values and exemptions.
- Run a permit history search with the Department of Planning and Permitting using the TMK.
- Order a preliminary title report using the TMK together with the legal description.
- If boundaries or improvements are in doubt, order a licensed survey that references the TMK and recorded descriptions.
- If you find discrepancies, contact the Real Property Assessment Division for clarification and document requests.
Trusted Honolulu resources
- City and County of Honolulu Real Property Assessment Division: official tax records, assessed values, owner-of-record, TMK lookup by address or owner
- Honolulu county GIS and mapping viewers: parcel maps, tax map images, and overlay layers like zoning and flood
- Department of Planning and Permitting: zoning lookups and permit history searches by TMK
- State Bureau of Conveyances: recorded deeds and instruments for chain of title cross-checks
- Title companies and licensed surveyors: definitive title reports, encumbrance searches, and boundary surveys that tie to the TMK
- State Office of Planning and Hawaii GIS: statewide hazard layers that can be queried using TMK-based parcel lookups
Put TMKs to work for you
When you know how to read a TMK, you can move faster and with more confidence. You will match listings to the correct parcel, verify details in minutes, and spot issues early. Whether you are preparing a listing or reviewing a property to buy, using the TMK as your anchor saves time and reduces risk.
If you want a local, people-first guide to help you apply this process to your specific property or search, reach out to Diane. You will get concierge support that makes due diligence clearer and more efficient. Connect with Diane Ito to map out your next step.
FAQs
What is a TMK number in Honolulu?
- A TMK is the county parcel identifier used to link a property to tax records, maps, zoning, permits, and other official data.
Is a TMK the same as a parcel number in Hawaii?
- Yes. TMK functions as Hawaii’s parcel number and is the standard identifier for county and state property databases.
Can two different properties share the same TMK in Honolulu?
- Generally no for distinct tax parcels, although condo projects may use related identifiers for individual units that go beyond the base parcel.
Will my TMK appear on my deed in Honolulu?
- Deeds often reference tax maps or legal descriptions; the TMK may appear in county indices and title reports even if not printed directly on the deed.
How do I find a condo unit’s TMK or identifier in Honolulu?
- Start with the base TMK for the project’s parcel, then use the official records or building documents to add unit identifiers required by the county system.
Does a TMK show liens, easements, or mortgages?
- No. A TMK does not reveal encumbrances. Order a title search or preliminary title report to review liens and easements.
