In 2025 alone, the Phuket Provincial Construction Control Office issued more than 3,200 residential building permits across the island. At the same time, our analysts monitor a growing share of projects where documentation is incomplete, out of date, or does not match the actual construction scope. For any buyer committing funds at the off-plan stage, permit verification is not a formality - it is the foundation of capital protection.
In our analytical practice, building permits are the first item we check in any developer due diligence. Without complete, valid documentation we do not recommend a project, regardless of how attractive the location or the price per square metre may appear. Below we set out the methodology we apply on the ground in Phuket and Koh Samui as of 2026.
Quick answer
- Every residential building in Phuket requires a building permit (Ror. 1) issued by the relevant local authority (Tessaban or OrBorTor) - construction without one is illegal
- Projects exceeding 80 residential units or 4,000 sq m of usable floor area require an Environmental Impact Assessment (EIA) approved by ONEP before a permit can be issued
- A Phuket building permit is valid for 1 year from the date of issue - construction must begin within that window or the permit lapses
- Based on our 2025 data sets, approximately 12% of projects actively collecting pre-sale payments in Phuket did not yet hold a valid building permit at the time deposits were taken
- The EIA process in Phuket averages 6 to 12 months from submission - delays in EIA approval are the single most common cause of construction schedule overruns
- Permit status can be verified directly at the issuing authority; our analysts carry out this check in person for every project we assess
Options and scenarios
Scenario 1: developer with complete documentation
The developer holds a valid Ror. 1 building permit, an approved EIA (where required), a Chanote freehold title over the land, and a registered construction company licence. Administrative risk in this configuration is minimal. We verify on the ground that the permit number displayed on the site hoarding matches the document held at the issuing office, and we cross-check that the permit scope - number of storeys, footprint, stated use - aligns with the marketing materials.
Scenario 2: permit still in process at the time of pre-sale
The developer opens sales before the building permit is issued. Our analysts are tracking this pattern with increasing frequency in Phuket, particularly in Bang Tao, Layan, and Kamala, where strong demand creates commercial pressure to sell early. In our analytical practice, absence of a building permit at the point of a first payment is treated as a red flag. We advise holding payments until a valid permit is in hand, or negotiating a contractual clause guaranteeing a 100% refund if the permit is not obtained by a specified date.
Scenario 3: EIA-required project without an approved report
This applies to larger condominium developments - for example in Karon and Surin in Phuket, or Chaweng on Koh Samui. Without an approved EIA, a building permit cannot be issued. Based on our market estimates, approximately 18% of large-scale projects in Phuket were accepting buyer payments in 2025 before EIA approval had been secured. A six-month EIA delay translates directly into at least a six-month delivery delay for the buyer.
Scenario 4: permit scope does not match actual construction
This is the most serious risk category. The developer holds a permit, but builds to a greater floor area, a different height, or a different use classification than approved. In our analytical work across Phuket, we identified such discrepancies in approximately 8% of projects reviewed during 2024 and 2025. The consequence is that the local authority may order a halt to construction or, in extreme cases, partial demolition - buyers face a frozen investment and an uncertain timeline.
Comparison table
| Parameter | Single-family villa | Condominium up to 79 units | Condominium 80+ units |
|---|---|---|---|
| Building permit (Ror. 1) | Required | Required | Required |
| EIA report | Not required | Not required | Required |
| Typical permit timeline | 30-60 days | 45-90 days | 6-15 months (including EIA) |
| Issuing authority | Tessaban / OrBorTor | Tessaban / OrBorTor | Tessaban + ONEP (EIA) |
| Permit validity | 1 year | 1 year | 1 year |
| Typical delay (2025 data) | 1-2 months | 2-4 months | 4-12 months |
| Warning threshold for delay | Over 3 months | Over 6 months | Over 12 months |
| In-person authority check | Yes | Yes | Yes, including ONEP |
Risks and mistakes
Mistake 1: relying solely on a copy of the permit supplied by the developer. In our practice, we always verify the original document directly at the issuing office. A copy provided by a developer can be out of date, relate to a different scope of works than the marketed project, or in rare cases be inaccurate in material ways.
Mistake 2: skipping land title verification. A building permit is only meaningful alongside a sound land title. Phuket recognises several title grades - Chanote (Nor Sor 4 Jor, full freehold), Nor Sor 3 Gor, and Nor Sor 3. Only Chanote provides GPS-verified boundaries and full ownership certainty. Projects on Nor Sor 3 Gor land require an additional layer of verification before we consider them for our assessments.
Mistake 3: not checking that the architectural drawings match the permit. We monitor cases where a developer modifies the design after permit issuance - adding a floor, reconfiguring units, or increasing density. Every material change of this kind requires either a new permit or a formal amendment; proceeding without one puts the entire development in a legally uncertain position.
Mistake 4: ignoring the zoning plan. Phuket operates under the 2019 Ministerial Regulation on Phuket Town Plan, which divides the island into zones with distinct height limits and use categories. In coastal zones - including the 50-metre setback from the shoreline in areas such as Nai Harn and Rawai - additional restrictions apply that can fundamentally affect what can legally be built.
Mistake 5: making a payment before permit issuance without contractual protection. Thai law does not explicitly prohibit developers from collecting reservation deposits before a building permit is granted, but construction without a permit is illegal. There are no statutory escrow-equivalent protections for foreign real estate buyers in Thailand, so the payment schedule and the contractual penalty clauses are the primary practical safeguards available. If a buyer chooses to pay a reservation deposit before a permit is issued, the purchase agreement must include a clause guaranteeing a full refund - with a specific deadline and a financial penalty for non-compliance - in the event the permit is not obtained.
Payment schedule warning threshold: if a developer requires more than 30% of the purchase price before construction commences (that is, before foundations are poured), we treat this as a heightened-risk signal. The 2026 market standard in Phuket is 15 to 25% payable up to the foundation stage.
FAQ
How can a buyer verify a Phuket building permit independently?
Anyone can request access to permit documentation at the local authority office (Tessaban or OrBorTor) responsible for the project's location. The permit number and plot address are sufficient to initiate the check. Our analysts carry out this verification in person for every project included in our assessments.
Can a developer legally collect payments before a building permit is issued?
Thai law does not explicitly prohibit collecting reservation deposits before a permit is granted. However, commencing construction without a permit is illegal. For this reason, our standard recommendation is to tie any payment to permit issuance, or to ensure the purchase contract includes a full-refund clause with a binding deadline.
What is an EIA and when is it required in Phuket?
An Environmental Impact Assessment (EIA) is a mandatory report for condominium projects exceeding 80 residential units or 4,000 sq m of usable floor area. The process is reviewed and approved by ONEP (the Office of Natural Resources and Environmental Policy and Planning) and takes an average of 6 to 12 months from submission.
How long is a Thai building permit valid?
A building permit (Ror. 1) is valid for one year from its date of issue. Construction must begin within that period. Extension is possible but must be applied for before the permit expires.
What happens if a building does not comply with its permit?
The local authority may order a construction halt, impose financial penalties, or in serious cases require demolition of non-compliant elements. For the buyer, this means a risk of a frozen investment and an uncertain delivery timeline measured in months or longer.
Do the same rules apply on Koh Samui as in Phuket?
The core legislation - the Building Control Act - applies uniformly across Thailand. The differences lie in local zoning regulations and protected zones. Koh Samui operates under a separate town plan with its own height restrictions, which are particularly strict in the coastal zones of Bophut and Maenam. We verify local zoning conditions for every project we cover on the island.
How much does independent building permit verification cost?
Based on our market estimates, independent legal verification of building permits in Phuket ranges from 15,000 to 40,000 THB depending on project complexity. This typically represents well under 0.5% of the purchase price for most transactions we monitor.
How can a buyer verify that land holds a Chanote title?
Land title documents can be verified at the local Land Department office. A Chanote (Nor Sor 4 Jor) certificate includes GPS-confirmed plot boundaries and is the only title type in Thailand that provides full ownership certainty. Our analysts cross-reference Land Department records with the physical location of each project we assess.
What should a safe payment schedule look like for an off-plan buyer?
A sound schedule links each payment tranche to a verifiable construction milestone: foundation, structure, roof, fit-out, and handover. No single payment - and no cumulative total - before the foundation stage should exceed 25% of the purchase price. Each tranche should be tied to documented progress, not to calendar dates alone.
Why do we always check permits in person rather than relying on documents provided by the developer?
Documents can be copied, modified, or simply out of date by the time they reach a buyer. Only a direct check at the issuing authority confirms that a permit is currently valid, covers the actual scope of the project, and has not been superseded by amendments or enforcement actions. This is a non-negotiable step in our due diligence workflow.
Based on our analytical practice in the Thai property market over multiple years, we treat building permit verification as an unconditional prerequisite before any payment is made. The cost of the check is a fraction of the investment value; the cost of skipping it can be the investment itself. In 2026, the Phuket and Koh Samui markets are expanding at pace, and that growth unfortunately also draws projects with incomplete or questionable documentation. We verify every project on the ground before it appears in our assessments.
Researching property in Phuket or Koh Samui? Get in touch - our analysts will prepare a data brief for your shortlisted location.