As Thailand enters fiscal year 2026 (beginning 1 October 2025), attention turns to how the Thai Revenue Department (TRD) plans to strengthen its revenue collection, following last year’s performance.

For fiscal year 2025 (October 2024 – September 2025), the Ministry of Finance reported total tax revenue of THB 2.33 trillion, an increase from the previous year, but still THB 37.2 billion (1.6%) below target[1]. In response to this shortfall, the TRD has indicated a multi-pronged strategy focused on enhancing collection efficiency through digital transformation and artificial intelligence (AI) driven management, conducting targeted tax audits based on high-risk factors and industries, and implementing the newly enacted measures.

To enhance accuracy, streamline operations, and improve tax collection efficiency, AI is being integrated into nearly every aspect of tax administration, from policy decision making and risk analysis to tax audit management and service delivery, under the IT Development Plan (2025–2027)[2]. This transformation will also enable tax officers to focus more on higher-value and higher-risk areas.

As the TRD’s use of AI continues to evolve, alongside intensified tax audit efforts in response to Thailand’s challenging business environment, its audit strategies are expected to become more sophisticated and data driven. This means the focus will likely shift toward taxpayers or industries that exhibit patterns of non-compliance or financial irregularities. Taxpayers should therefore take proactive steps to review their tax positions and strengthen compliance documentation in the coming years.

While the TRD has not formally disclosed detailed guidelines or scoring criteria for risk assessments, recent developments and focus areas provide insights into where its attention may be heading. The following section highlights some of the key risk areas, emerging tax audit trends and development of newly enacted tax measures that businesses should be aware of going forward.

Key Risk Areas and Emerging Tax Audit Trends

1. Related-Party Transactions

With access to information such as transfer pricing disclosure forms and CbCR reports, and the adoption of AI-driven tools to identify high-risk taxpayers, the TRD can now conduct more targeted and data-informed audits.

Businesses need to reassess their transfer pricing (TP) policies to ensure they fall within the arm’s length range, as profitability below the range may be flagged as a risk factor. TP documentation should be kept up-to-date, and the selected profit point must be well-supported by the company’s functional, risk, and asset (FRA) profile, along with benchmarking against comparable market peers.

Significant related-party transactions may be highlighted by the AI tools; therefore, they should be supported by strong documentation, such as agreements, invoices, receipts, and evidence of benefits received. Compliance with applicable taxes, including Value Added Tax (VAT), Withholding Tax (WHT), Specific Business Tax (SBT) and Stamp duty (SD), should also be thoroughly reviewed, as supporting documents may be requested during a tax audit.

2. Cross-Agency Data Matching and Discrepancy Review

Thailand’s tax landscape is undergoing a significant digital transformation, driven by enhanced inter-agency data integration. One of the key developments is the formalized data-sharing framework between the TRD and the Customs Department (CDT), which enables the exchange of electronic receipt and import VAT data[3]. This integration enhances the Risk-Based Audit (RBA) system by allowing authorities to efficiently cross-reference customs, VAT, and corporate tax records. As a result, discrepancies can be identified promptly and accurately.

Businesses with significant cross-border transactions would likely face increased visibility and audit risk. Any discrepancies between tax, customs, and accounting records should be proactively reviewed and validated to ensure compliance.

3. Profit Declines and Tax Losses

Thailand’s business environment in 2024–2025 remains challenging due to weak domestic demand, rising costs, and global uncertainty. To survive or stay competitive, many companies need to undergo significant changes in business structures, such as restructurings, group reorganizations, or business model transformations. These strategic shifts often involve significant upfront costs (e.g., restructuring costs, relocation and facility costs), particularly during the initial stages, which could lead to Thai companies suffering losses or declined profitability. As a result, the TRD could raise questions and scrutinize the transactions more closely, especially when such change takes place at the time Board of Investment (BOI) tax holiday expires.

Businesses need to be able to document and explain the reasons behind the losses or profit declines. Clear business plans and realistic financial forecasts are essential to support the company’s position.

4. Tax Refund

Following consecutive losses or declining profits, especially in the service sector, companies may seek tax refunds for prepaid WHT, which typically triggers a tax audit. The complexity of the audit is influenced by many factors including the TRD’s risk-based assessment, the refund amount, the company’s compliance history, and the consistency of its tax filings. The TRD may intensify scrutiny using AI tools to detect risk indicators, requiring detailed documentation to support refund claims.

Interestingly, choosing not to request a refund does not automatically exempt companies from audits, as excess tax submissions without claims can still trigger a review.

As a part of risk management, companies can have tax health checks to identify areas that require more attention and to beef up documentation to support their position and expedite audit outcomes. If there is uncertainty about whether all transactions fully comply with tax laws and are properly documented, companies can generally still request a tax refund within three years from the due date of filing the relevant tax returns.

5. BEPS 2.0/Pillar Two – Global Minimum Tax

As of 1 January 2025, Thailand enacted the Emergency Decree on Top-up Tax, aligning with the OECD’s Pillar Two global minimum tax framework.[4] In-scope businesses (i.e., Thai entities in MNE groups with consolidated revenue of at least EUR 750 million in two of past four fiscal years) face new reporting obligations.

Although some regulations remain in draft or consultation stages, the TRD is proactively preparing its personnel for the new regime. In August 2025, the TRD launched a training program focused on Pillar Two procedures, led by senior officials[5]. This initiative forms part of a broader strategy to build internal capacity ahead of implementation and enforcement.

Multinational enterprises must assess their Pillar Two exposure, prepare supporting documentation for top-up tax calculations, and closely monitor upcoming ministerial regulations expected to clarify key areas such as safe harbors, calculation methods, and compliance procedures.

6. Industry-Specific Audit Focus by the TRD

The TRD has increased scrutiny on certain high risk or hard to monitor sectors, particularly those with digital or cash-based operations. These include digital economy and e-commerce, influencer marketing, restaurants and nightlife businesses, cash-based trading and pharmacies.

These industries are being targeted due to potential underreporting, limited documentation, and complex transaction flows. With AI-driven audit tools and inter-agency data sharing, businesses in these sectors should strengthen recordkeeping, ensure tax compliance, and be prepared for increased audit visibility.

How A&M Can Help

A&M provides a comprehensive range of tax services to support businesses across all stages of their operations.

• Tax health check review: Assess overall tax compliance, identify potential non-compliance issues, quantify tax exposures, and provide practical recommendations.
• Tax compliance service: Collaborate closely with companies to ensure all tax obligations are accurately fulfilled and submitted on time.
• Tax audit assistance: Act as an intermediary between the TRD and taxpayers to facilitate communication, manage audit processes, and ensure efficient audit closure.
• Tax advisory: Provide strategic and practical advice on key transactions including Pillar Two implementation, business restructuring, business model transformation, mergers and acquisitions, or spin-offs.
• Internal process review: Work with companies to evaluate finance and accounting processes, identify improvement opportunities, and enhance operational tax efficiency.