Every month, VAT-registered businesses in Thailand calculate their output and input VAT and file a return to pay the net amount due or claim a refund. Yet a common and costly dispute arises when a business that has paid input VAT to its supplier—and done everything asked of it—later finds that input VAT rejected on the grounds that the tax invoice was issued by “a person not entitled to issue tax invoices.” In these cases, a buyer may have confirmed the supplier’s VAT registration on the Revenue Department’s website, paid through the banking system, received a complete tax invoice, and kept full payment and inventory records. Even so, if the Revenue Department later determines that the supplier did not genuinely make the sale or collected the VAT without remitting it, the department can disallow the input VAT and assess additional tax, surcharge, and penalty—often more than a year after the transaction. A new article from tax and dispute resolution specialists at Tilleke & Gibbins in Bangkok examines how the Revenue Department and the courts approach these disputes, including two recent Supreme Court (Tax Division) decisions confirming that the taxpayer bears the burden of proving a supplier genuinely sold and delivered the goods and received payment. It considers why the VAT registration system offers no legal safe harbor, why the evidentiary burden falls hardest on online and cross-border transactions where buyers and sellers never meet, and how the Revenue Department’s own digital infrastructure could detect non-remitting suppliers at the source rather than shifting the loss to good-faith buyers. The article also sets out practical guidance: how to build a comprehensive “know-your-supplier” file at the time of a transaction, the procedural steps and strict deadlines for challenging a VAT assessment, and why dispute readiness belongs alongside tax planning at the center

Tilleke & Gibbins has contributed the Thailand and Vietnam chapters to Investigations in Southeast Asia, a comprehensive guide published by Drew Network Asia (DNA). The resource provides a practical overview of anticorruption laws, corporate investigations, and compliance frameworks across six key Southeast Asian jurisdictions. Designed for in-house counsel, compliance officers, and risk management professionals, the guide offers actionable insights for navigating complex cross-border regulatory challenges and establishing effective, regionally coordinated compliance and investigation strategies. The guide begins with a regional perspective on enforcement trends and cross-border cooperation initiatives. Jurisdiction-specific chapters follow a standardized structure—covering primary corruption offenses, enforcement authorities, corporate liability, investigation procedures and dawn raids, whistleblower protections, and recommended compliance measures. In addition to country-by-country analysis, the publication highlights best practices for conducting internal investigations, managing digital evidence, and handling parallel proceedings involving multiple regional or international regulators. The guide serves as a practical reference for organizations operating in Southeast Asia. Because legal and regulatory risks depend on specific industry sectors and operational contexts, readers seeking tailored advice are encouraged to contact the authors listed in each chapter. The full guide is available for download through the button below or directly from the DNA website.

Doing business in Thailand means operating under a strict regulatory framework. From time to time, companies may receive unexpected administrative orders from government authorities that restrict their operations, impose new compliance obligations, or levy fines and penalties. When this happens, a business may challenge the order under Thailand’s administrative law system. The primary concern in pursuing administrative litigation is timing, as strict statutory deadlines apply and missing them can permanently affect a company’s rights. First Step: Administrative Appeal Many companies assume the first step is to immediately bring the matter before the Administrative Court to seek revocation or suspension of the order. Some even attempt to request an interim injunction to stop the order from taking effect. However, Thai law generally requires that the company first challenge the order through an administrative appeal with the same agency that issued it. Only after this process is complete can the matter be taken to court. Seeking an interim injunction at this stage is also not possible. This is because Thai law does not allow a standalone application for an interim injunction; an injunction can only be requested together with the underlying complaint filed with the Administrative Court. Since a court complaint cannot be filed until the administrative appeal process has been exhausted, an injunction is usually not available at the early stage. What Are the Timeframes for Administrative Appeal? Thailand applies a two-stage administrative appeal process. The appeal must first be submitted to the same authority that issued the order, which will review its own decision. If that authority affirms its decision, the appeal is then escalated to the relevant higher authority for further review. In most cases, both stages must be completed before a company is allowed to proceed to court. The timeframe for filing an administrative appeal is very

Attorneys from Tilleke & Gibbins have updated the latest edition of Doing Business in Thailand, a Q&A-style guide from Thomson Reuters Practical Law that offers an overview of key legal considerations for companies operating in jurisdictions worldwide. The contribution outlines the country’s legal and regulatory framework for foreign investment and business operations and reflects the latest legislative developments. The chapter addresses the following core topics: Legal system: Structure of the courts and the codified nature of Thai law. Foreign investment: Business restrictions under the Foreign Business Act, sector-specific regulations, exchange control rules, and investment incentives. Business vehicles: Overview of partnerships, private and public limited companies, and other legal entities. Employment: Labor protections, employment contracts, foreign worker requirements, and termination procedures. Tax: Corporate and personal income tax, indirect taxes, and tax obligations for residents and non-residents. Intellectual property: Registration and enforcement of patents, trademarks, designs, and copyrights. Data protection: Key provisions of the Personal Data Protection Act and related compliance obligations. Competition law: Regulatory framework under the Trade Competition Act. Anti-bribery and corruption: Relevant legislation and enforcement mechanisms. E-commerce and digital business: Legal regime for online transactions and digital platforms. Marketing and advertising: Consumer protection laws and regulations affecting advertising and marketing practices. Product regulation and liability: Safety standards, liability regimes, and roles of enforcement authorities. Practical Law, a legal reference resource from Thomson Reuters, publishes a range of guides for hundreds of jurisdictions and practice areas. The insurance and reinsurance guide is a valuable resource for legal practitioners, covering numerous jurisdictions worldwide. To view the latest version of the guide, please visit the Practical Law website and enroll in the free Practical Law trial to gain full access.