Due diligence is the set of checks that confirm a property in Thailand is legally sound, free of hidden debts and safe to buy — carried out before you transfer a single baht. For a foreign buyer it is the most important stage of the whole purchase: it verifies the title deed, uncovers any mortgages or encumbrances, confirms your right to own the unit, and — for a new development — tests whether the developer can actually deliver. This 2026 checklist walks through every property due diligence item in plain language, from title checks to the condo juristic person, so you know exactly what should be verified and who should do it.
Why due diligence matters
Thailand has no title insurance and no automatic buyer protection — the principle is very much buyer beware. The market is cash-based, and once ownership is transferred at the Land Office, unwinding a bad purchase is slow and expensive. Due diligence is how you find problems before they become yours.
For foreign buyers there is an extra layer, because your right to own depends on the structure: a condo in the foreign-freehold quota, a villa on a registered leasehold, or a property held through a Thai company. Each carries its own checks. The good news is that thorough due diligence is inexpensive relative to the sums at stake, and it follows the same disciplined process whether you are buying a modest condo or a multi-million-baht villa. For the wider journey, our pillar guide on how to buy property in Phuket sets the context.
Timing matters, too. Due diligence typically runs after your offer is accepted and the unit is reserved, but before you sign the Sale and Purchase Agreement or transfer any funds — the reservation window exists precisely so these checks can be completed. If anything material turns up, you still have the leverage to renegotiate, require a fix, or walk away with your position protected.
Verify the title deed
Everything starts with the title deed, because it proves what is being sold and who owns it.
- Confirm the deed type. A Chanote (Nor Sor 4 Jor) is the strongest and most secure title in Thailand — a fully surveyed, accurately marked freehold deed. Lesser documents offer weaker guarantees of boundaries and rights, so the deed type materially affects what you are buying.
- Confirm the owner. The seller named on the contract should be the registered owner on the deed held at the Land Office, with identity documents that match.
- Check the land itself for a villa: the deed's stated area and boundaries should match the plot on the ground.
Your lawyer obtains a certified copy from the Land Office and compares it against the seller's documents — a step you should never take on trust.
Encumbrances, access and zoning
A clean-looking deed can still carry problems registered against it or attached to the land:
- Mortgages and encumbrances. Check whether the title has a mortgage, lien or other charge registered on it. These must be cleared on or before transfer, or they follow the property to you.
- Legal access. Confirm the land has a proper right of way — legal, not merely physical, access to a public road. Landlocked plots and informal access arrangements are a classic Phuket pitfall.
- Zoning and permits. Verify the zoning allows the current or intended use, that any building permit is valid, and that coastal setbacks or environmental rules — common near Phuket's beaches and hillsides — have been respected.
Condo checks: foreign quota and the juristic person
For a condominium, two checks are specific and essential.
First, foreign-quota availability. A building can sell up to 49% of its floor area into foreign freehold; confirm in writing that your specific unit is available within that quota, because it determines whether you take foreign freehold or a leasehold instead. Our guide to freehold vs leasehold in Phuket explains the difference and why it matters.
Second, the juristic person — the entity that runs the building. Ask for:
- Any outstanding common-area fees owed on the unit, as unpaid balances can block the transfer.
- The sinking fund and reserve position — is the building financially healthy?
- The juristic person's debts, management quality and recent meeting minutes, which reveal how well the building is actually run.
For a villa or land purchase, the emphasis shifts to the land title, boundaries, legal access and any company structure, all of which need checking with particular care because you are dealing with land rather than a registered condo unit.
Vetting a developer for a new build
If you are buying off-plan or a brand-new unit, your due diligence extends to the developer, because both your money and your finished home depend on them:
- Track record — completed projects you can visit, delivered on time and to standard.
- Financial strength and land ownership — confirm the developer owns the land outright and is well capitalised to finish the build.
- Permits and title — the building permit and land title are genuinely in place, along with any required environmental approval.
Reluctance to share permits, references or a clear written contract tells you what you need to know. Developer vetting deserves exactly the same rigour as any title check. It is also worth confirming how your stage payments are protected — through an escrow arrangement where available, or milestones tied to verified progress — so your money stays aligned with the work actually completed on site.
A practical due-diligence checklist
Use this as a working checklist with your lawyer before you transfer any money:
- Title deed verified at the Land Office, ideally a Chanote, in the seller's name.
- No mortgages, liens or encumbrances registered against the title, or a clear plan to discharge them at transfer.
- Legal access confirmed, along with correct zoning, permits and setbacks.
- Foreign-quota availability confirmed in writing for a condo unit.
- Juristic person checked: no unpaid fees on the unit, a healthy sinking fund, no concerning debts.
- For a new build: developer track record, financials, land ownership, building permit and land title all verified.
- Source of funds and FET planned, so foreign currency arrives correctly for freehold registration and any future repatriation.
- Contract reviewed and every finding reflected in the Sale and Purchase Agreement before signing.
Our buyer's guide includes tools and checklists that complement this list.
Who does the work, and what it costs
Due diligence should be carried out by an independent lawyer who represents you — not the developer's in-house team and not the agent's affiliate — so the advice is genuinely on your side. A good lawyer handles the title search, the encumbrance and quota checks, contract review, and completion, and can act under a Power of Attorney if you are buying from abroad.
Fees are modest against the risk: typically around THB 30,000–60,000 for a standard condo or leasehold purchase, and more where a Thai company structure or a complex deal is involved. That is one of the best-value line items in the entire transaction. To understand the role fully, see do you need a lawyer to buy property in Thailand?, and for the contract stage that follows, our guide to the sale and purchase agreement in Thailand.
Conclusion
Due diligence is not a formality to rush through — it is the stage that protects your money. Verify the title, clear any encumbrances, confirm access and zoning, check the quota and the juristic person, vet the developer, and make sure every finding is written into your contract. Do that with an independent lawyer, and you remove almost all of the risk that catches unprepared buyers.
Planning a purchase in Phuket? Browse our verified listings or arrange a free consultation, and we will help you run each of these checks before you commit.
