International tax advice for businesses in Thailand

International tax has entered a period of once-in-a-generation change, as coordinated global corporate tax reform, including the OECD’s Pillar Two rules, moves from proposal to law. Our worldwide presence allows us to give strategic advice on these long-term shifts, as well as help you navigate today’s complex tax rulebooks.

International tax advice for businesses operating from Thailand

Our approach 

Companies that operate across borders, or hold a presence in multiple jurisdictions, know that complying with local tax laws and meeting reporting requirements is a resource-intensive task. It demands local market expertise from trained professionals, and access to reliable cross border tax advice. 

Our global network is ideally suited to serve large multinationals and global-minded mid-sized companies who need on-the-ground expertise in multiple jurisdictions. We also have substantial expertise helping fast-growing companies who need a tax-efficient structure for their first international expansion. The network means we have a clear view not only of the global trend but an on-the-ground view of disruptive, single-country initiatives such as national taxes on digital services. 

We have a particular focus on corporate structures. Whether it is the reshaping of global tax rules through the OECD Base Erosion and Profit Shifting (BEPS) action plan, the introduction of Pillar Two, or disruptive single-country measures, the risk of tax nexus is a growing and constant concern for businesses. We can help on issues such as international tax transparency. Navigating such an ever-evolving business environment increasingly requires an integrated, global approach with access to coordinated advice that can support your strategy and business decisions for the long term. 

Tax planning for outbound investment from Thailand

As Thai businesses expand overseas, effective international tax planning becomes central to protecting returns and managing risk. Tax planning for outbound investment from Thailand involves more than choosing a destination market. It requires a clear view of how profits will be earned, financed, repatriated, and taxed across each jurisdiction in the structure. 

Our team helps Thai-headquartered groups and privately owned businesses plan the tax profile of their overseas investment from the outset. We advise on holding and financing structures, the use of Thailand’s double tax treaty network to manage withholding tax on dividends, interest, and royalties, the availability of foreign tax credits, and the practical steps needed to align tax, legal, and commercial objectives. Early planning helps you avoid unnecessary tax leakage and build a structure that remains efficient as your overseas operations grow.

Pillar Two and top-up tax compliance in Thailand

Thailand has implemented the OECD’s Pillar Two global minimum tax through the Emergency Decree on Top-up Tax, B.E. 2567 (2024), which applies to in-scope multinational groups for accounting periods beginning on or after 1 January 2025. The rules introduce a 15% global minimum effective tax rate and can require a top-up tax where the effective tax rate of a group’s Thai operations falls below that level. For many groups, this makes pillar 2 compliance a new and ongoing obligation rather than a one-off exercise.

Is your group within scope?

The Top-up Tax rules apply to multinational enterprise groups with consolidated group revenue of EUR 750 million or more in at least two of the four preceding financial years. If your group meets this threshold and has constituent entities in Thailand, those entities can fall within the scope of the Thai rules, even where the ultimate parent sits in another jurisdiction. We help you confirm whether your group is in scope, identify which entities are affected, and understand how the Domestic Top-up Tax, the Income Inclusion Rule, and the Undertaxed Profits Rule may apply to your structure.

How we support Pillar Two readiness

Preparing for Pillar Two draws on financial reporting, tax, and data in equal measure. Our pillar 2 tax services in Thailand support you across the full readiness cycle: assessing scope, gathering and testing the data needed to calculate GloBE income and covered taxes, modelling your effective tax rate by jurisdiction, and preparing the information required for Top-up Tax filings. We work alongside your finance and tax teams so that reporting is accurate, consistent, and defensible.

Reviewing the impact on incentives and effective tax rates

Thailand’s headline corporate income tax rate is 20%, but groups benefiting from investment incentives, including Board of Investment (BOI) promotion, may have an effective tax rate below the 15% minimum. Where that happens, a top-up tax can apply and reduce the real value of those incentives. Thailand has confirmed that BOI incentives will be restructured to align with Pillar Two rather than withdrawn, with a Qualified Refundable Tax Credit (QRTC) as the centrepiece. Because a QRTC counts as income for the global minimum tax calculation, it can deliver benefits without pushing a group’s effective tax rate below the threshold. We review how Pillar Two interacts with your existing and future incentives, model the effect on your effective tax rate, and help you plan around the transition so that investment decisions reflect the post-Pillar Two position.

Our services include:

• International tax advisory drawing on our global tax expertise 
• Providing expatriate tax services 
• Structuring cross-border real estate transactions 
• Supporting transfer-pricing policies and international financing operations 
• Advising on cross-border mergers and acquisitions 
• Determining the most tax-efficient way to structure foreign offices 
• Structuring the funding of an overseas business, taking into consideration the tax laws of the respective countries 
• Managing the effective rate of tax and assisting with the timing of transactions 
• Assessing and supporting Pillar Two and Top-up Tax compliance for groups operating in Thailand 

Our tools and solutions 

Our international tax network develops a range of tools and resources to support clients managing cross-border obligations, including trackers and technical guidance on major international tax developments such as Pillar Two.

Cross-border tax and permanent establishment reviews

Double tax treaty and cross-border payment reviews

Cross-border payments such as dividends, interest, royalties, and service fees can attract withholding tax in more than one country. Through our cross border tax Thailand reviews, we check how Thailand’s double tax treaties apply to your payment flows, whether treaty relief or reduced withholding rates are available, and what documentation is needed to support a claim. This helps you avoid paying more tax than the rules require and reduces the risk of disputes with the authorities.

Permanent establishment risk assessment

Sending staff overseas, appointing agents, or running project work in another country can create a permanent establishment, and with it a taxable presence and filing obligations you may not have planned for. We assess where your activities could create a permanent establishment, both for Thai businesses operating abroad and for foreign businesses operating in Thailand, and advise on how to structure operations and contracts to manage that risk. This forms part of the practical cross border tax advice we provide throughout the life of a project.

FAQs International tax advice for businesses in Thailand

Q: What information should a business prepare before seeking international tax advice?

A: Prepare an outline of the group structure, the jurisdictions involved, planned transactions, financial projections, key contracts, payment flows, and any existing tax incentives or tax registrations. This allows advisers to identify the relevant tax questions and determine which jurisdictions need to be reviewed.

Q: When should international tax advice be obtained during an overseas expansion?

A: Advice is most useful before the legal entity is incorporated, capital is committed, contracts are signed, or employees begin operating in the new market. Early review helps ensure that tax, legal, operational, and financing decisions are aligned from the outset.

Q: Can international tax advice support a transaction involving multiple countries?

A: Yes. A coordinated international tax engagement can assess the Thailand implications alongside requirements in the countries where the parties, assets, financing, employees, or customers are located. This is especially valuable when a transaction involves several interconnected entities or payment flows.

Q: Does international tax advice apply only to large multinational groups?

A: No. It is also relevant to growing Thai businesses making their first outbound investment from Thailand, foreign companies entering Thailand, privately owned groups, and businesses with cross-border contracts or employees. The scope should be tailored to the complexity and commercial objective of the business.

Q: How does an international tax review differ from annual tax compliance?

A: Annual compliance focuses on meeting recurring filing obligations. An international tax review focuses on the tax implications of structures, transactions, operations, and cross-border changes, then identifies actions that may be needed before or alongside compliance work.

Q: Does my group need to comply with Pillar Two in Thailand?

A: If your multinational group has consolidated revenue of EUR 750 million or more and has entities in Thailand, it may fall within Thailand’s Top-up Tax rules for accounting periods beginning on or after 1 January 2025. A pillar 2 compliance review confirms whether you are in scope, how the rules affect your effective tax rate, and what data and filings are required.