Reviewed by ThaiLawOnline, a licensed Thai law firm practising in Thailand since 2006. Thai lawyer of record: Wichuda Atthamethakon, LL.M., Thai Bar Licence 3149/2556.
Last updated on September 5, 2026
Due diligence (การตรวจสอบสถานะทรัพย์สิน, kan truat sop, also called a title search or property check) in a Thai property transaction is the investigation a buyer carries out before paying for land, a house or a condominium unit to confirm that the seller owns what is being sold, that the title is what it claims to be, that nothing registered or unregistered will spoil the purchase and that the buyer can legally hold it. Thai law does not require it, and there is no title insurance to fall back on, so the buyer bears the loss when it is skipped.
Table of Contents
What a Thai property due diligence covers
The core is a search at the Land Office where the property is registered, using the title deed number. A certified copy of the deed is compared with the seller’s document, since forged and duplicate deeds exist, and the back page is read for encumbrances: mortgages, leases, usufructs, servitudes, court seizures and any restriction on transfer. The type of document matters as much as the name on it; only a Chanote or Nor Sor 3 Gor gives a right that can safely be bought, while Sor Kor 1 and Por Bor Tor 5 papers do not.
The second layer concerns the seller and the building. For an individual seller, the ID card, marital status and, for married Thais, the spouse’s consent are checked, along with any power of attorney. For a company seller, the affidavit, shareholder list and a board resolution to sell are obtained from the Department of Business Development. For a house or a new project, the building permit (Or. 1), the completion certificate and, for large developments, the environmental impact approval are examined, together with the zoning plan at the municipality. Litigation and bankruptcy searches complete the picture.
Where foreign buyers most often skip it
Off-plan condominiums and villa estates are where most money is lost. The buyer pays a reservation and instalments on the strength of a brochure, and only at transfer discovers that the land is mortgaged to the developer’s bank, that the foreign quota is full, or that the building was never registered as a condominium. Checks on the developer’s title, mortgage, permits and track record before the first payment cost a fraction of what is at stake.
For land bought through a Thai spouse or a lease, the same Land Office search applies, plus a check that the plot is not inside a forest reserve, a national park or agricultural reform land, none of which the seller’s paper will reveal. Access is verified by reading the deeds of every plot between the property and the public road for a registered servitude.
The Land Office search takes hours; a full report on a resale unit typically takes two to four weeks, and a large development one to three months. The common mistake is to ask the selling agent to do it, since the agent is paid only if the sale completes.
What goes wrong without due diligence
The recurring cases are predictable. A buyer pays for a plot with a Por Bor Tor 5 receipt and later learns that it is state land. A lessee takes a 30-year lease on land already mortgaged, and the bank forecloses. A foreigner funds a company that holds land through nominee shareholders and, when the Department of Business Development investigates, faces imprisonment, a fine and the forced sale of the land. A deposit is paid on a unit outside the foreign quota and the developer keeps it.
| Check | Where | What it reveals |
|---|---|---|
| Title search and back page | Land Office | Ownership, deed type, encumbrances, seizures |
| Seller and developer records | DBD, courts | Authority to sell, litigation, insolvency |
| Permits and zoning | Municipality, district office | Lawful construction and permitted use |
| Quota and debt-free letters | Condominium juristic person | Foreign quota, unpaid fees |
Once the transfer is registered, the buyer’s remedy is a claim against the seller for the price and damages, worth only what the seller still owns in Thailand.
Frequently asked questions
What does property due diligence in Thailand include?
A certified title search at the Land Office to confirm ownership, deed type and registered encumbrances; checks on the seller’s identity and authority, or a company seller’s registration and resolutions; verification of building permits, environmental approvals and zoning; litigation and bankruptcy searches; and, for a condominium, the foreign quota letter and debt-free certificate.
How long does due diligence take when buying a condo in Thailand?
The Land Office search can be done in a day. A full report on a resale condominium unit usually takes two to four weeks, and a check on an off-plan project or a large land purchase one to three months, depending on how quickly the developer produces its documents.
Can I do the due diligence myself?
The Land Office will issue a certified copy of a title deed to anyone who asks, so parts of it are possible without help. Reading the Thai-language back page, checking the zoning plan, searching court records and reviewing a company seller’s documents are harder, and mistakes are only discovered after the money is paid.
See also: Encumbrance on a Thai title deed, Chanote, Escrow, Nominee, Property Due Diligence in Thailand and Risks of Buying Property in Thailand.
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