Thailand BOI updates foreign staff and workforce rules.
Thailand’s Board of Investment has introduced updated compliance requirements for BOI-promoted companies under Announcement No. Por. 8/2568, effective April 2026. The changes cover minimum salary thresholds for foreign employees, documentation standards for work permit applications and renewals and workforce composition rules for manufacturing firms. The new requirements have been phased in, with companies holding promotion certificates issued on or after 5 June 2025 subject to the rules from 1 October 2025, and those with certificates issued before that date required to comply from 1 January 2026.
Salary thresholds and work permit documentation
The BOI has introduced minimum salary thresholds for foreign nationals employed under BOI promotion. To support this requirement, companies must provide formal employment contracts for all new work permit applications. This includes clearer withholding tax documentation to verify payroll compliance.
For work permit renewals, withholding tax documentation must be submitted to confirm that income has been properly declared. In addition, from 13 February 2026, companies are required to provide a certified copy of PND 1 or PND 1 Kor issued by the Revenue Department. Previously accepted uncertified copies are no longer sufficient.
Where a third party is engaged to obtain certified tax documents, companies must arrange an appointment letter through the Revenue Department system and ensure a valid Power of Attorney is in place. Processing timelines may extend by several business days, requiring earlier preparation for renewals.
These measures strengthen alignment between immigration filings and tax records, increasing the level of due diligence required from employers. As a result, companies may face longer preparation times and closer review from authorities.
Workforce composition requirements for manufacturing firms
Alongside the documentation changes, manufacturing companies with more than 100 employees will face additional obligations to maintain at least 70% Thai workforce composition. Exemptions may apply for smaller companies or under special conditions as determined by the BOI. This requirement must be supported by monthly social security contribution records, creating an ongoing compliance obligation rather than a periodic reporting exercise.
For companies with certificates issued on or after 5 June 2025, submissions through the Single Window system began on 1 October 2025 using August 2025 contribution data. For companies with earlier certificates, submissions began on 1 January 2026 using November 2025 data.
Expanded social security reporting obligations
From 9 April 2026, the requirement to submit social security contribution evidence has been extended to all BOI-promoted companies. Previously, this obligation applied primarily to manufacturing businesses.
Under the updated framework, service companies and manufacturing companies with fewer than 30 employees must submit contribution evidence annually by 28 February. Manufacturing companies with more than 30 employees must submit proof of their most recent contributions every three months, with filings due by the 15th of the relevant month.
Applications submitted to the BOI without the required social security documentation will not be accepted. Authorities have also clarified acceptable tax documentation for visa extension applications. Both certified and non-certified documents may be used, provided all relevant pages display the same tax reference number.
These updates significantly increase the administrative and compliance burden for BOI-promoted companies, particularly those employing foreign staff. Documentation requirements are now more formalised, deadlines are tighter and certification standards have been elevated. Businesses should review internal processes across payroll, tax and human resources functions to ensure readiness, and plan ahead where third-party representatives or Power of Attorney arrangements may be needed.
