Thailand: New Rules Forthcoming for Board of Investment-Promoted Companies

Update April 9, 2026: The Thai authorities have introduced further changes affecting companies promoted by the Board of Investment (BOI):  

• Notably, the requirement to submit Social Security Contribution (SSC) payment evidence has now been expanded to apply to all BOI-promoted businesses, whereas previously it applied only to manufacturing companies. Under the new rules, service companies and manufacturing companies with fewer than 30 employees must submit SSC payment evidence once per year by February 28. In contrast, manufacturing companies with more than 30 employees are required to submit proof of their most recent monthly SSC contributions every three months, with submissions due by the 15th of each month (for example, January contributions must be submitted by 15 January). Without the required SSC, the BOI application will not be accepted.
• In addition, the authorities have clarified acceptable tax documentation for visa extension applications. Applicants may submit either tax documents certified by the Revenue Department or non-certified documents, provided that the cover page, the page displaying the foreign national’s name, and the payment receipt page all bear the same tax reference number.

February 13, 2026: In relation to tax requirements for renewal applications, BOI companies are now required to submit a certified copy of PND 1 or PND 1 Kor (PND 1), issued by the Revenue Department, as a supporting document. Previously, a scanned uncertified copy of the PND 1 / PND 1 Kor was sufficient for renewal applications. Under the revised practice, certification of tax document is mandatory, and uncertified copies may no longer be accepted.  

If a company requires third party assistance to obtain the required tax certification, additional documentation and procedural steps apply:  

• • The company must first request an appointment letter for the third party representative through the Revenue Department (RD) system. Following issuance of the appointment letter, the processing time to obtain the certified document is approximately four business days.  
  • The company must also ensure that a valid Power of Attorney (POA) is in place, signed by an Authorized Director, authorizing the third party representative to act on the company’s behalf. Where the existing POA does not include a Thai Director as a signatory or does not expressly cover the scope of obtaining tax certification from the RD, a new POA is required. Arrangements for execution of the POA may further extend overall processing timelines. 

August 20, 2025: Following the new policy below, manufacturing companies must submit the certificate of social security contributions via the Single Window system. For those who receive their BOI certificate on or after June 5, 2025, submission begins on October 1, 2025, using the August 2025 contribution. For companies that received their BOI certificate before June 5, 2025, submission begins on January 1, 2026, using the November 2025 contribution.  

June 27, 2025: The Thailand Board of Investment (BOI) has announced key updates applicable that will apply to companies promoted by the BOI.    

First, there will be minimum salary threshold changes. To demonstrate proof of salary, employers will need to provide an employment contract for all new work permit applications; and withholding tax documents for renewal applications.        

Additionally, for BOI-promoted companies in the manufacturing sector, companies with more than 100 employees will need to ensure that at least 70% of their workforce consists of Thai nationals. Exemptions may apply in certain cases, such as for smaller companies or under special conditions. Monthly social security contribution documents must be submitted as proof of the number of Thai employees. Currently, there is no local worker quota.   

These changes will take effect starting October 1, 2025 for companies with BOI-promoted certificates issued on or after June 5, 2025; and January 1, 2026 for companies with certificates issued before June 5, 2025.