How Can a Buyer Verify a Phuket Property’s Building Permit?

Concise answer

A buyer should verify a Phuket property’s building permit directly with the municipality or subdistrict administrative organisation responsible for the land—not rely only on a copy supplied by the developer, seller or agent.

The principal document is usually Form Or.1, the permit authorising construction, alteration or demolition. However, Thai building-control law also permits an alternative notification procedure under Section 39 bis, so the absence of an Or.1 permit does not automatically mean construction is unlawful. Where Section 39 bis was used, the buyer should verify the official notification receipt, approved plans, professional certifications and the authority’s project file.

The verification should confirm:

• Permit or notification number
• Issuing authority
• Applicant and building owner
• Land-title numbers
• Exact construction location
• Number and type of buildings
• Approved use
• Number of floors
• Approved building area and height
• Issue and expiry dates
• Renewals
• Approved amendments
• Authority-stamped plans
• Environmental and other conditions
• Whether construction matches the approved design
• Whether a completion or controlled-use certificate is required and has been issued

A genuine building permit proves only that specified construction was authorised according to specified plans. It does not by itself prove:

• Land ownership
• Legal road access
• Valid land subdivision
• Environmental approval
• Hotel operation rights
• Condominium registration
• Construction quality
• Completion
• Compliance with every permit condition
• Foreign ownership eligibility

The safest method is for the buyer’s independent Thai lawyer and qualified architect or engineer to inspect the complete authority file and compare it with the land, completed buildings and transaction documents.

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Detailed explanation

1. A building permit is project-specific

A building permit does not provide a general right to construct anything on the land.

It ordinarily relates to defined matters such as:

• Identified land plots
• Named applicant
• Particular building or buildings
• Approved use
• Building position
• Dimensions
• Height
• Floor area
• Number of floors
• Structural design
• Setbacks
• Parking
• Access
• Drainage
• Wastewater systems
• Other approved plans and conditions

The buyer must confirm that the document covers the actual property being purchased.

2. The principal legal framework

Building construction in Thailand is principally governed by the Building Control Act B.E. 2522 (1979), as amended, together with:

• Ministerial regulations
• Local ordinances
• Town-planning rules
• Phuket environmental-protection measures
• Professional engineering and architectural requirements
• Other project-specific legislation

Section 21 provides that a person constructing, altering or moving a building must either:

• Obtain permission from the competent local official; or
• Notify the official and comply with the alternative procedure under Section 39 bis.

The current consolidated Building Control Act is available through the building-law resources maintained by Thailand’s architectural and government authorities. Building Control Act consolidated text

3. Form Or.1 is the usual construction permit

The document commonly called a building permit is Form Or.1.

Its Thai description covers permission to:

• Construct a building
• Alter a building
• Demolish a building

The permit should not be confused with the application form. A submitted application does not constitute permission.

A typical permit identifies:

• Permit number
• Year
• Owner or permit holder
• Building location
• Relevant land title
• Nature of work authorised
• Building type and use
• Approved plans
• Issue date
• Expiry date
• Conditions
• Issuing official

An official construction-permit guide includes the Or.1 form and shows that applications are supported by land evidence, site plans, construction drawings, calculations and professional documentation. Government construction-permit guide

4. The application is not the permit

The application is generally made using Form Khor.1.

A developer may show the buyer:

• Application form
• Receipt
• Submission number
• Architect’s drawings
• Engineering calculations
• Appointment confirmation
• Correspondence with officials

These documents may show that an application has been made. They do not necessarily establish that permission has been granted.

The buyer should ask specifically:

Has the building permit been issued, or has only an application been submitted?

5. Section 39 bis creates an alternative route

Thai building-control law permits a qualified alternative notification process under Section 39 bis.

Under this route, the owner may submit:

• Required notification
• Site plan
• Building plans
• Supporting calculations
• Licensed architect’s certification
• Licensed engineer’s certification
• Construction-supervision documentation
• Other required evidence

The local authority issues an official receipt or acknowledgement of notification.

Government service guidance states that the authority should issue the notification receipt within the applicable service period after the required documents and fees have been accepted. The authority retains power to examine the project and order corrections where the notified plans or construction do not comply with the law. Thai government service information on Section 39 bis

6. No Or.1 does not always mean no lawful authority

A salesperson may say:

“There is no Or.1 because the project uses Section 39 bis.”

That explanation is legally possible, but it must be documented.

The buyer should request:

• Official notification receipt
• Date of receipt
• Authority receiving the notification
• Complete submitted plans
• Professional certifications
• Architect and engineer licences
• Supervising professionals
• Any authority inspection reports
• Correction orders
• Revised submissions
• Confirmation that required fees were paid
• Current status of the notification

Section 39 bis should not be used as a vague explanation for missing records.

7. A Section 39 bis receipt is not immunity from enforcement

The notification procedure does not allow the owner to ignore:

• Building-control requirements
• Town-planning restrictions
• Environmental measures
• Height restrictions
• Setbacks
• Structural-safety rules
• Professional standards
• Parking requirements
• Drainage and wastewater requirements

If the authority later finds non-compliance, it may require corrections or take enforcement action.

The buyer must therefore verify both the procedural documents and substantive compliance.

8. The correct issuing authority depends on location

Phuket contains several municipal and subdistrict jurisdictions.

The relevant authority may be:

• City municipality
• Town municipality
• Subdistrict municipality
• Subdistrict administrative organisation
• Another legally competent local authority

The permit should be verified with the authority having jurisdiction over the precise land parcel—not merely whichever office is most convenient.

A project marketed as being in “Bang Tao,” “Rawai,” “Kamala” or “Phuket Town” still requires confirmation of the exact administrative boundary.

9. Start with the land-title numbers

The permit must be reconciled with the property’s land documents.

The buyer should obtain:

• Chanote or other land document
• Land-title number
• Land number
• Survey-page number
• Subdistrict
• District
• Province
• Plot map
• Current title endorsements
• Subdivision history

The land-title references in the building file should match the land on which the building actually stands.

10. Marketing addresses are insufficient

A project may be marketed under:

• Estate name
• Resort name
• Villa number
• Sales-office address
• Google Maps location
• Informal road name
• Phase name

These identifiers may not appear in the official records.

Verification should be based on:

• Land-title details
• Official cadastral location
• Permit number
• Legal project owner
• Authority records

“Villa 12” in a brochure is not necessarily “Building 12” in the permit.

11. Confirm the applicant and building owner

The name on the permit may be:

• Developer company
• Landowner
• Previous landowner
• Project subsidiary
• Individual director
• Seller
• Contractor
• Earlier project company

A difference is not automatically improper, but it requires explanation.

The buyer should determine:

• Who applied
• Who owned the land at the time
• Whether landowner consent was provided
• Whether the permit or project rights were lawfully transferred
• Whether the current developer is entitled to continue construction
• Whether corporate name changes are documented

12. Landowner consent may be required

Where the permit applicant did not own the land, the authority file may contain the landowner’s written consent.

The buyer should inspect:

• Landowner identity
• Consent wording
• Land plots covered
• Buildings authorised
• Conditions
• Revocation provisions
• Relationship between landowner and developer

Landowner consent to construction is not necessarily equivalent to transferring ownership of the land or building.

13. The permit should cover the actual building type

The approved use might be:

• Single residential house
• Collective residential building
• Condominium
• Apartment
• Hotel
• Commercial building
• Restaurant
• Office
• Clubhouse
• Mixed-use building
• Service or utility building

The buyer should compare the permitted use with the actual and advertised use.

A building approved as a private residence is not automatically approved for:

• Hotel operation
• Daily rentals
• Restaurant use
• Spa operation
• Commercial events
• Public entertainment
• Office use
• Dormitory use

14. Hotel operation requires separate analysis

A building permit does not constitute a hotel licence.

A project marketed as a:

• Condotel
• Resort residence
• Managed villa
• Branded residence
• Guaranteed-return property
• Holiday-rental investment

may require separate hotel-law compliance.

The buyer should verify:

• Approved building use
• Completion certification
• Hotel licence or lawful exemption
• Rental-management structure
• Condominium rules
• Environmental classification
• Fire and safety compliance

The building permit answers only part of the operating question.

15. Check every building on the property

A villa purchase may include more than the main house:

• Guest pavilion
• Staff quarters
• Garage
• Carport
• Pool
• Sala
• Gym
• Office
• Guardhouse
• Plant room
• Retaining walls
• Boundary structures
• Storage building
• Restaurant or clubhouse

The buyer should establish which structures appear on the approved plans.

A valid permit for the principal villa does not necessarily legalise later additions.

16. Swimming pools should be checked

A swimming pool may be shown:

• On the approved site plan
• In structural drawings
• Under a separate permit
• As a later approved alteration
• Nowhere in the approved file

The buyer should compare:

• Pool location
• Dimensions
• Setback
• Structural design
• Plant room
• Drainage
• Overflow
• Distance from boundaries
• Relationship with retaining walls

A pool built differently from the approved design may require correction or retrospective approval where legally available.

17. Retaining walls are especially important in Phuket

Hillside projects frequently depend on:

• Retaining walls
• Cut-and-fill works
• Slope stabilisation
• Foundations
• Drainage channels
• Soil anchors
• Excavation
• Boundary walls

These structures may create serious regulatory and safety concerns if they were:

• Not included in the approved plans
• Built beyond the land boundary
• Constructed differently from the engineering design
• Added without required permission
• Built on public or neighbouring land
• Inadequately drained

A structural engineer should inspect material hillside works.

18. Confirm the approved number of floors

The buyer should compare the approved plans with the actual building.

Common discrepancies include:

• Additional basement
• Enclosed undercroft
• Rooftop room
• Converted parking area
• Mezzanine
• Extra bedroom
• Staff accommodation
• Roof terrace
• Expanded plant room
• Additional storey created by excavation

How a level is legally counted may depend on technical definitions. A buyer should not decide this from appearances alone.

19. Confirm approved height

Phuket developments may be affected by:

• Building-control limits
• Town-planning rules
• Environmental-protection zones
• Coastal restrictions
• Hillside and elevation controls
• Local ordinances
• Airport-related restrictions

Height may be measured according to legally defined points rather than the marketing description.

A permit should be reviewed together with:

• Survey levels
• Approved elevations
• Finished ground level
• Roof design
• Later site alteration

20. Confirm the building footprint and setbacks

The approved site plan should show the building’s position relative to:

• Land boundaries
• Roads
• Neighbouring land
• Shoreline
• Waterways
• Other buildings
• Utility areas
• Parking
• Access
• Environmental zones

A properly issued permit does not protect an owner who later constructs outside the approved footprint.

21. Check approved floor area

The buyer should compare:

• Approved building area
• Advertised built-up area
• Interior area
• Saleable area
• Actual measured area
• Title or condominium area
• Later extensions

These measurements may use different definitions.

A larger actual building may indicate:

• Approved amendment
• Marketing measurement difference
• Unauthorised extension
• Enclosed terrace
• Added room
• Expanded basement
• Incorrect sales information

22. Obtain the authority-stamped plans

The permit is only part of the approval.

The buyer should obtain the plans officially associated with it, including where applicable:

• Site plan
• Floor plans
• Elevations
• Sections
• Structural drawings
• Foundation details
• Roof plan
• Parking plan
• Drainage plan
• Wastewater system
• Fire-safety systems
• Electrical or mechanical plans
• Calculations
• Specifications

The plans should carry the relevant signatures, stamps or authority references.

An unstamped sales plan is not evidence of approval.

23. Compare the approved plans with the sales plans

Off-plan buyers should compare the official design with:

• Brochure
• Reservation plan
• Contract plan
• Furniture plan
• Show villa
• Virtual rendering
• Master plan
• Facility schedule

Differences may include:

• Unit layout
• Villa size
• Balcony
• Pool
• Parking
• Common facilities
• Building orientation
• View corridor
• Number of neighbouring units
• Road position
• Clubhouse
• Landscaping

The contract should identify which plans are legally binding.

24. Compare the approved plans with the finished property

For a resale property, a qualified architect or engineer should conduct an as-built comparison.

The review may identify:

• Added rooms
• Extended roofs
• Enclosed balconies
• Converted garages
• Expanded kitchens
• Pool changes
• Additional bathrooms
• Staff quarters
• Boundary encroachment
• Changed stairways
• Structural openings
• Unapproved retaining walls

A visually attractive renovation may still be an unauthorised alteration.

25. Alterations may require permission

Building-control obligations can apply not only to new construction but also to material alterations.

Examples requiring investigation include:

• Structural changes
• Additional floor area
• Added storey
• Changed load-bearing elements
• Major roof changes
• New staircase
• Altered fire escape
• Conversion of parking
• Change of use
• Large extension
• Major retaining works

The precise requirement depends on the nature and scale of the work and applicable law.

26. Verify amendment approval

If the approved design changed, the developer should provide evidence of the relevant approval or notification.

The buyer should request:

• Amendment application
• Revised authority-stamped plans
• Amendment permit or approval
• Section 39 bis revision documents
• Architect’s and engineer’s certifications
• Authority correspondence
• Revised environmental approval where required

A developer’s internal “revision drawing” is not necessarily an approved amendment.

27. Form Or.6 may relate to approved-plan amendments

Thai building-control forms include procedures for changing approved:

• Site plans
• Building plans
• Supporting specifications
• Calculations

Where such a change was required, the buyer should verify that the authority formally accepted or approved it through the correct procedure.

The form number alone is less important than confirming that the final constructed design is covered by the authority’s current file.

28. Check issue and expiry dates

Building permits are normally issued for a defined period.

Under the relevant ministerial rules, the original duration is generally based on the area being constructed or altered:

These periods should be checked against:

• Permit issue date
• Stated expiry date
• Construction commencement
• Progress
• Renewal applications
• Renewal endorsements
• Final completion

The Council of State has explained the area-based periods and renewal framework under the relevant ministerial regulations. Council of State opinion concerning building-permit renewal

29. An expired permit requires investigation

An expired permit does not necessarily mean that an already completed building is automatically unlawful.

The buyer must establish:

• What work was completed while permission was valid
• Whether construction continued after expiry
• Whether renewal was requested in time
• Whether renewal was granted
• Whether a new permit was issued
• Whether incomplete work remains
• Whether the authority issued orders
• Whether later law affected renewal

For an unfinished project, the permit’s current status is particularly important.

30. Verify every renewal

A photocopy of the original permit may not show the full history.

The buyer should request:

• Renewal application
• Approval
• Endorsement
• Updated expiry date
• Progress report
• Inspection records
• Conditions attached to renewal
• Later replacement permit

The local authority’s file should be treated as more reliable than a loose collection of developer copies.

31. Multiple buildings may share one permit

A development may have:

• One permit for several buildings
• Separate permits for each building
• Permit covering only one phase
• Separate infrastructure permits
• Separate amendments
• Buildings added later

The buyer should identify exactly where the purchased property sits within the permit structure.

A project-wide permit should be checked for:

• Total buildings
• Relevant building number
• Phase
• Construction status
• Renewal calculation
• Completion status

32. A permit for Phase 1 does not automatically cover Phase 2

A developer may show a genuine permit that covers only:

• Sales gallery
• Show villa
• Clubhouse
• First condominium building
• Initial villa phase
• Site office

The buyer should not assume it covers the whole advertised master plan.

The permit documents must identify the purchased building or unit.

33. A show villa permit does not prove the sale villas are approved

A completed show villa can give buyers confidence, but it may stand on:

• Different land
• Commercial or temporary site
• Separate permit
• Different design
• Different structural system
• Land outside the sale phase

The buyer should verify the permit for the actual plot being purchased.

34. A house registration book is not a building permit

A blue or yellow house-registration book is used for administrative registration.

It does not necessarily prove:

• Lawful construction
• Compliance with approved plans
• Ownership
• Valid completion certification
• Permitted commercial use
• Hotel legality
• Absence of encroachment

The existence of a house number should not replace building-permit verification.

35. Electricity and water connections are not conclusive

A building may have:

• Electricity meter
• Water connection
• Internet
• Postal address
• Utility bills

These services do not conclusively establish that the building was legally constructed or completed in accordance with its permit.

Utility records are supporting evidence—not substitutes for the authority file.

36. Land Office registration does not verify every building issue

A land title records land rights. It does not necessarily contain or guarantee:

• Building permit status
• Approved floor area
• Building-plan compliance
• Construction quality
• Hotel legality
• Environmental compliance
• Completion certification

A registered land transfer can occur without the Land Office performing a full technical audit of every structure.

37. A permit does not prove building ownership

A permit may identify the person authorised to construct, but it is not necessarily conclusive proof of current building ownership.

Building ownership may require examination of:

• Land ownership
• Construction contract
• Payment records
• Permit
• House registration
• Sale agreement
• Registered superficies
• Lease terms
• Court decisions
• Previous transfers
• Tax and utility evidence

This is particularly important where a foreign buyer purchases a villa building while leasing the land.

38. A permit does not prove legal road access

The approved plan may show an entrance or road, but the buyer must separately verify whether access is legally secured.

The road could be:

• Public road
• Private development road
• Easement
• Informal access
• Revocable permission
• Road on another company’s land
• Unregistered route

Building approval should not replace title and easement searches.

39. A permit does not prove valid land subdivision

A villa development may require land-allocation approval under the Land Development Act.

A building permit for an individual villa does not necessarily prove that:

• The estate subdivision was approved
• Roads and utilities comply with land-allocation requirements
• Common facilities are legally secured
• Individual plots can be transferred as promised
• Required guarantees were provided

Building and land-development approvals should be reviewed separately.

40. Environmental approval remains separate

Where a project requires an EIA or IEE, the building-permit review should confirm:

• Environmental approval was obtained
• Permit plans correspond with the environmentally approved design
• Environmental conditions were incorporated
• Later changes were addressed
• Current construction does not materially exceed the approved project

PR-KC-040 addresses the environmental-approval process separately.

41. Completion documentation may be required

For buildings classified as controlled-use buildings, the owner may need certification after construction or alteration is completed and before the building is lawfully used for its controlled purpose.

The buyer should investigate whether the property requires:

• Completion inspection
• Form Or.5 certification
• Fire-safety inspection
• System testing
• Other use-related approval
• Change-of-use permission

A construction permit authorises construction. It does not always provide final authority to occupy or operate the completed building for every proposed use.

42. Form Or.5 is particularly important for regulated buildings

Form Or.5 generally concerns certification that construction, alteration or relocation of a controlled-use building has been completed in accordance with the authorised requirements.

Depending on the property, this may be relevant to:

• Condominium buildings
• Hotels
• Large buildings
• High-rise buildings
• Commercial buildings
• Other controlled-use categories

The buyer’s lawyer and technical adviser should determine whether it is legally required for the specific building.

43. A villa may not require the same completion certificate as a condominium

The documentation required for a small private house may differ from that required for:

• High-rise condominium
• Large residential building
• Hotel
• Commercial development
• Public-use building

The absence of a particular completion form should not be assessed without first classifying the building.

44. Condominium registration involves additional checks

A condominium building cannot be assessed only through its construction permit.

The buyer should also verify:

• Condominium registration
• Condominium juristic person
• Individual unit title
• Common property
• Unit areas
• Ownership ratios
• Foreign quota
• Environmental approval
• Controlled-use certification
• Developer land and mortgage status

A permit issued during development does not by itself guarantee later condominium registration.

45. Forged or incomplete copies are possible

Warning signs include:

• Missing permit number
• Missing issuing authority
• Blurred seal
• Altered dates
• Mismatched company names
• Mismatched title numbers
• Missing pages
• Plans without official stamps
• Permit covering a different building
• Unexplained handwritten amendments
• English-only “certificate”
• Refusal to provide authority access
• Document supplied only as a cropped image

The buyer should verify authenticity directly with the issuing authority.

46. The authority file is more important than one document

The complete building-control file may include:

• Application
• Land evidence
• Landowner consent
• Permit
• Notification receipt
• Approved plans
• Calculations
• Architect and engineer documents
• Amendment applications
• Inspection reports
• Renewal records
• Completion certificate
• Correction notices
• Stop-work orders
• Enforcement correspondence

A single permit page cannot reveal the entire history.

47. Access to records may require cooperation

Depending on the authority and record, the buyer or lawyer may need:

• Seller’s consent
• Developer authorisation
• Power of attorney
• Permit number
• Title documents
• Formal written request
• Appointment with the engineering department
• Thai-language request

A seller’s refusal to cooperate should be treated as a material due-diligence concern.

48. Technical comparison requires a qualified professional

A lawyer can review legal documents, but may not be qualified to determine whether the finished building matches structural and architectural plans.

A buyer may need:

• Thai property lawyer
• Licensed architect
• Licensed civil or structural engineer
• Surveyor
• Environmental consultant
• Building inspector

Their functions are complementary.

49. Surveying may reveal location discrepancies

A survey can establish whether:

• Building sits within the title boundary
• Pool crosses a boundary
• Retaining wall encroaches
• Access road follows the registered route
• Approved setbacks are maintained
• Buildings occupy the correct plots
• Coastal or waterway boundaries are affected

A building can resemble its approved design while still being constructed in the wrong location.

50. Enforcement risk should be assessed realistically

Where construction violates building-control law, authorities may potentially issue orders concerning:

• Suspension of construction
• Prohibition of use
• Correction
• Alteration
• Removal
• Demolition
• Compliance within a stated period

There may also be criminal and financial consequences under applicable law.

The practical outcome depends on:

• Nature of violation
• Ability to correct it
• Location
• Applicable law
• Authority action
• Building safety
• Environmental restrictions
• Court proceedings

A buyer should not assume every violation can be resolved retrospectively.

51. Retrospective approval is not guaranteed

A seller may promise:

• “We can legalise it later.”
• “Everyone builds this way.”
• “The municipality knows about it.”
• “It is only a small extension.”
• “The official will approve it.”
• “The fine is minor.”

Retrospective approval may be impossible where the building breaches:

• Height limit
• Setback
• Land-use restriction
• Environmental zone
• Structural requirement
• Road-width rule
• Boundary
• Public-land restriction
• Building-density control

The legalisation route should be confirmed before purchase.

52. Contract protection is essential

The sale agreement may require the seller or developer to warrant that:

• Required permission was obtained.
• Permit information supplied is complete and authentic.
• Construction complies with approved plans.
• No unauthorised alterations exist.
• No stop-work, correction or demolition order exists.
• No unresolved building-control proceeding exists.
• Required completion documents will be delivered.
• Buyer may inspect the authority file.
• Seller must correct specified defects before transfer.
• Buyer may terminate if a material permit problem cannot be resolved.

The enforceability and remedies should be reviewed under Thai law.

53. Off-plan payments should be linked to permit status

Before making substantial construction-linked payments, the buyer should verify:

• Construction authority exists
• Permit remains effective
• Purchased building is covered
• Environmental approval is complete where required
• Land mortgage and ownership are understood
• Construction milestone is genuine
• Work matches approved plans

A developer should not treat the buyer’s payment as a substitute for obtaining the required permissions.

54. Resale buyers also need verification

Building-permit risk is not limited to off-plan purchases.

A resale villa may contain years of owner modifications, such as:

• Added bedroom
• Extended kitchen
• Enclosed terrace
• Staff room
• Garage conversion
• Rooftop sala
• Larger pool
• New retaining wall
• Additional storey
• Commercial rental facilities

The older the property, the more important it may be to reconstruct the building and alteration history.

55. Independent legal and technical review is the safest approach

Before buying, the buyer’s advisers should confirm:

• Correct issuing authority
• Permit or Section 39 bis route
• Authenticity
• Permit holder
• Land titles
• Landowner consent
• Approved use
• Number of buildings
• Floors
• Area
• Height
• Setbacks
• Pool
• Retaining structures
• Access
• Plans
• Amendments
• Issue date
• Expiry date
• Renewals
• Environmental approvals
• Completion documents
• As-built compliance
• Authority orders
• Legalisation options
• Contractual remedies

The objective is not merely to find a document called a permit. It is to establish that the property the buyer will receive is the property legally authorised to exist.

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Building-permit document comparison

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Building-permit risk comparison

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Practical buyer checklist

A buyer verifying a Phuket building permit should:

1. Obtain the property’s exact legal location.
2. Identify the competent municipality or subdistrict authority.
3. Obtain all relevant land titles.
4. Confirm land-title numbers against the permit.
5. Obtain the complete Form Or.1 permit.
6. Determine whether Section 39 bis was used instead.
7. Obtain the official Section 39 bis receipt where applicable.
8. Confirm the permit or notification number.
9. Confirm the issue date.
10. Confirm the expiry date.
11. Obtain every renewal.
12. Confirm the current validity where construction continues.
13. Identify the permit holder.
14. Identify the landowner at the application date.
15. Obtain landowner consent where applicable.
16. Review any transfer or corporate-name documents.
17. Confirm the approved building use.
18. Confirm the number of buildings.
19. Confirm the number of floors.
20. Confirm the building height.
21. Confirm approved floor area.
22. Confirm the approved footprint.
23. Confirm setbacks.
24. Confirm parking.
25. Confirm road entrance.
26. Confirm drainage.
27. Confirm wastewater systems.
28. Confirm swimming-pool approval.
29. Confirm retaining-wall approval.
30. Obtain the complete authority-stamped plans.
31. Obtain structural drawings.
32. Obtain relevant calculations.
33. Obtain architect and engineer certifications.
34. Verify professional licences where material.
35. Obtain all approved amendments.
36. Compare the official plans with the sales plans.
37. Compare the official plans with the finished building.
38. Conduct a site survey where boundaries are material.
39. Check all extensions and renovations.
40. Determine whether a completion certificate is required.
41. Obtain Form Or.5 where applicable.
42. Check environmental approvals separately.
43. Check land-development permission separately.
44. Check condominium registration separately.
45. Check hotel licensing separately.
46. Check legal road access separately.
47. Ask the authority about correction or stop-work orders.
48. Ask about complaints and enforcement proceedings.
49. Require seller cooperation with the authority search.
50. Include appropriate warranties in the sale agreement.
51. Require correction before transfer where possible.
52. Retain sufficient payment until documentation is complete.
53. Avoid relying only on house books and utility bills.
54. Avoid relying only on the developer’s photocopies.
55. Obtain independent Thai legal, architectural and engineering advice.

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Greg’s professional perspective

A building permit should never be treated as a box to tick simply because the developer emails one page carrying an official-looking stamp.

Before recommending a Phuket property, I want clear answers to seven questions:

1. Which authority issued the permission?
2. Does it cover the correct land?
3. Does it cover the exact building being purchased?
4. Was the Or.1 permit route or Section 39 bis notification route used?
5. Was the work completed while the permission remained effective?
6. Does the actual building match the approved plans?
7. Are all necessary amendments and completion documents in place?

The distinction between a permit and a compliant building is critical. A genuine permit may have been issued, but the developer or owner may subsequently have added another floor, enlarged the building, moved the pool or constructed retaining walls that were never approved.

The opposite mistake should also be avoided. A property should not automatically be described as illegal merely because there is no Or.1 document if the owner properly followed the Section 39 bis notification procedure. The correct records must be identified and verified.

For off-plan property, I would verify the permit before substantial construction payments. For a resale villa, I would compare the approved plans with the property as it stands today. In both cases, the issuing authority’s file matters more than sales assurances.

Phuket Realtor helps buyers verify that the attractive property they see is supported by the approvals it needs. That is how buyers Invest with Confidence.

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Applicable date

Current as reviewed on: 21 September 2026

Thai building-control legislation, ministerial regulations, Phuket environmental measures, local ordinances and administrative procedures may change. Local practice can also differ depending on the responsible municipality or subdistrict authority.

This entry should be reviewed following amendments to the Building Control Act, new ministerial regulations, Phuket environmental-control changes or material changes in local permitting procedures.

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Location and property types

Location: Phuket, Thailand
Primary property types: Villas, houses, condominiums, apartments, hotels, branded residences, commercial buildings and mixed-use developments
Transaction types: Off-plan purchase, completed developer property and resale
Buyer type: Foreign and Thai purchasers, investors, retirees and holiday-home buyers
Primary issue: Verifying that the building was properly authorised and corresponds with the officially approved plans

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Verified legal and authoritative sources

• Building Control Act B.E. 2522 (1979), as amended, Section 21 — requires permission or compliance with the Section 39 bis notification procedure before constructing, altering or moving a building.
• Building Control Act, Section 21 bis — concerns structural-design and calculation review for prescribed building categories.
• Building Control Act, Section 29 — concerns construction supervision and related professional documentation.
• Building Control Act, Sections 32 and 33 — concern controlled-use buildings and changes of building use.
• Building Control Act, Section 39 bis — provides the alternative professional-certification and notification procedure.
• Building Control Act, Section 39 ter — provides authority powers where a Section 39 bis submission or construction does not comply.
• Building Control Act, Sections 40–43 — provide enforcement powers concerning unlawful or non-compliant construction or use.
• Ministerial Regulation No. 10 B.E. 2528, as amended by Ministerial Regulation No. 57 B.E. 2544 — addresses permit duration and renewal.
• Consolidated Building Control Act reference — consolidated Thai text containing the principal statutory provisions.
• Government construction-permit guide and sample forms — explains supporting documents and contains sample Khor.1 and Or.1 forms.
• Thai government service portal: Section 39 bis procedure — official procedural information concerning the alternative notification route.
• Council of State opinion concerning permit duration and renewal — discusses the area-based duration and renewal framework.
• Department of Public Works and Town & Country Planning land-use service — official system for examining applicable land-use plans and planning requirements.
• Department of Public Works and Town & Country Planning — principal national authority for building-control and town-planning matters.
• Phuket municipalities and subdistrict administrative organisations — responsible for local permitting, notifications, inspections and enforcement within their respective jurisdictions.
• Council of Engineers Thailand and Architect Council of Thailand — relevant to professional licensing and regulated design or supervision work.
• Royal Gazette — definitive publication source for legislation, ministerial regulations and applicable notifications.

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Related questions

• What is a Thai Form Or.1 building permit?
• What is a Khor.1 building-permit application?
• What is the Section 39 bis building-notification procedure?
• Can a Phuket project build without an Or.1 permit?
• How can a buyer identify the correct permit authority?
• How long is a Thai building permit valid?
• Can a building permit be renewed?
• What happens if a permit expires during construction?
• Does a building permit transfer when project land is sold?
• Does the permit need to match the land-title number?
• Can several buildings share one permit?
• Does a Phase 1 permit cover later phases?
• Does a show-villa permit cover the villas being sold?
• How can a buyer obtain authority-stamped plans?
• What happens if the completed building differs from the approved plans?
• Does an extension require a new permit?
• Can an unauthorised extension be legalised?
• Does a swimming pool need to appear in the approved plans?
• Do retaining walls require approval?
• How are building height and floors measured?
• What is a Form Or.5 completion certificate?
• Does a house-registration book prove lawful construction?
• Does an electricity meter prove the building is legal?
• Does a land title prove the villa was legally constructed?
• Does a permit prove ownership of the building?
• Does a permit prove legal road access?
• Does a permit prove valid land subdivision?
• Does a permit replace EIA approval?
• Does a building permit allow hotel operation?
• Can a residential villa operate as a hotel?
• What enforcement action can be taken against an illegal building?
• What warranties should a property seller provide?
• Who should compare the completed building with the approved plans?
• What permit documents should an off-plan buyer receive?
• What should a buyer do if the seller refuses authority verification?

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Knowledge-catalog administration

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Disclaimer

This entry provides general educational information and does not constitute legal, architectural, engineering, planning, environmental, construction, investment or financial advice.

Building-permit requirements depend on the property’s location, classification, size, use, design, construction history and the law in force. A document should not be assumed authentic, current or applicable to the property without verification through the competent authority.

Buyers should obtain case-specific advice from qualified independent Thai legal and technical professionals before signing an unconditional agreement or transferring substantial funds.