Four things you can check yourself, for free, before paying a deposit
Before you send anybody the first payment, there are four sets of information you can pull from government systems at no cost: the appraised value, the location and shape of the parcel, the land use zoning, and any expropriation decree in the Royal Gazette.
All four together take under an hour, and each answers a different question, so none of it is duplicated work.
What none of them shows is the encumbrances recorded on the back of the title deed, which is why the last step still happens at the land office.
The appraised value, at the Treasury Department's system
Appraised values can be searched at the Treasury Department's published appraisal system at assessprice.treasury.go.th, which covers land, condominium units and buildings and is produced together with the Land Department.
This figure is not the market price. It is the base used to calculate the 2% transfer fee and the withholding tax on transfer day, so it is the number that sets the actual cost for both sides.
The most direct benefit of knowing it in advance is being able to work out transfer-day costs yourself before agreeing who pays which part. The whole calculation is in our article on the tax on selling a home.
One thing to keep in mind is that appraised values are revised in cycles. The new schedule taking effect in 2027 is expected to rise and it interacts with the fee reduction for homes priced near THB 7 million, as covered in our article on the new appraisal round.
Location and parcel shape, at the Land Department's LandsMaps
The Land Department runs a parcel map service, LandsMaps, at landsmaps.dol.go.th, where you can find a parcel and see its position, its shape and its area from the department's parcel database.
What to compare is the shape in the system against the shape on the copy of the deed the seller sent, and the position against what you saw on site. A plot whose frontage is not what the listing claimed, or whose access is not where you assumed, shows up at this stage before you spend a day travelling.
This service answers where and how big. It does not answer who and what rights. A deed number you can find does not confirm who owns it today or whether it is mortgaged.
For the different classes of land document and what each means for financing and resale, see our article on Thai land title deed types.
Zoning, before you plan anything on the land
The comprehensive plan decides what a parcel may be used for. In Bangkok it can be checked through the Department of City Planning and Urban Development at webportal.bangkok.go.th/cpud, and in other provinces through the Department of Public Works and Town and Country Planning at dpt.go.th.
Zoning answers the questions a price per square wah never does, such as the fact that land in a low-density residential zone cannot carry a tall building, and that green-zone land carries use restrictions tighter than most homebuyers expect.
A buyer purchasing a home to live in may assume this is somebody else's problem. It runs both ways: it governs what the neighbours may build in future, and it governs the land value when you sell.
Expropriation routes, at the Royal Gazette
Expropriation begins with a royal decree defining the land to be expropriated, published in the Royal Gazette, searchable at ratchakitcha.soc.go.th by project name or by the area you want to check.
A concrete example is the royal decree defining land to be expropriated for the Orange Line project from Bang Khun Non to the Thailand Cultural Centre, published in the Royal Gazette in 2024 and covering a number of areas across Bangkok.
The limit of a self-service check is that a decree describes the boundary in words and in the map annexed to it, not as a list of deed numbers. Confirming whether a specific parcel falls inside the line means asking the agency running the project or the local land office.
What to ask the seller directly is whether they have ever received a notice from any agency about a survey or an expropriation. A vague answer is a reason to check further, not a reason to move on.
What the online systems do not show, and the land office visit
Encumbrances live in the register of rights on the back of the title deed, not on an online map. Mortgages, injunctions, servitudes, usufructs and the history of transfers are all recorded there.
The direct route is to request a certified copy of the deed at the land office where the parcel sits, then read the whole reverse side rather than only the front, which is where the area is stated.
A workable order is: search the appraised value, then the location and shape, then the zoning, then the Royal Gazette, and finish with the certified copy of the deed. All of it belongs before the deposit, not before the transfer date.
If you are the owner about to sell, running the same set before you set an asking price lets you answer a buyer's questions on the spot and removes the haggling that comes from uncertainty. Our approach is on the land selling service page.
Frequently asked questions
Where can I check a land appraisal value online?
At the Treasury Department's published appraisal system, assessprice.treasury.go.th, which covers land, condominium units and buildings and is produced together with the Land Department.
Is the appraised value different from the market price?
Yes. The appraised value is the base for fees and taxes on transfer day, not what the market pays, so it is useful for estimating costs but not for setting an asking price.
Where can I see the shape of a parcel online?
At the Land Department's LandsMaps service, landsmaps.dol.go.th, which shows position, parcel shape and area from the department's parcel database.
Where do I check zoning?
In Bangkok, through the Department of City Planning and Urban Development at webportal.bangkok.go.th/cpud; elsewhere, through the Department of Public Works and Town and Country Planning at dpt.go.th.
Can I find out whether land is in an expropriation route?
You can make a first check through the royal decrees defining land to be expropriated in the Royal Gazette at ratchakitcha.soc.go.th, but a decree describes the boundary in words and an annexed map rather than by deed number, so confirmation has to come from the project agency or the land office.
Do the online systems show mortgages?
No. Mortgages, injunctions, servitudes and the transfer history sit in the register of rights on the back of the deed, which means requesting a certified copy at the land office.
When should all this be done?
Before the deposit, because once a deposit is paid your negotiating position weakens and the refund terms may not favour the buyer.
If I check it myself, do I still need an agent or a lawyer?
The online checks answer where the parcel is, what it is appraised at, what it may be used for and whether a decree exists. Reading the register of rights, drafting the contract and setting the transfer-day conditions are work worth having a professional on.
Summary
- Appraised values are searchable at the Treasury Department's system and form the base for the transfer fee and withholding tax.
- Position, parcel shape and area are available at the Land Department's LandsMaps.
- Zoning is available from Bangkok's Department of City Planning and Urban Development, or the Department of Public Works and Town and Country Planning elsewhere.
- Expropriation can be checked first through royal decrees in the Royal Gazette, then confirmed with the agency running the project.
- Mortgages, injunctions and servitudes never appear online; they require a certified copy of the deed and a reading of the reverse side.
- The order that works is appraised value, parcel, zoning, gazette, certified copy, all of it before the deposit.