Thailand Joins Global Minimum Tax Agreement

Thailand has taken another step towards participating in the international global minimum tax framework by signing an agreement on the exchange of tax information needed to support the collection of additional taxes from large multinational companies.

The agreement is part of the OECD-led effort to establish a minimum effective corporate tax rate of 15% for large multinational enterprises. The framework is designed to reduce incentives for companies to shift profits to jurisdictions where they face very low tax rates.

Thailand introduced its own top-up tax rules in 2025 as part of the implementation of the OECD’s Pillar Two framework. The rules generally apply to multinational groups with consolidated annual revenue of at least €750 million in at least two of the four preceding financial years.

Under the system, companies whose effective tax rate in a jurisdiction falls below 15% may face an additional tax payment to bring the rate up to the minimum level.

The Thai government has been developing the necessary legislation and administrative systems to collect the additional tax domestically. Earlier this year, the Cabinet approved measures supporting Thailand’s participation in the international tax framework and information-sharing arrangements.

The Revenue Department expects the global minimum tax to generate additional revenue for Thailand. Officials have previously estimated that the measure could bring in around 10 billion baht a year.

The agreement on tax information exchange is intended to improve cooperation between tax authorities and provide access to information needed to determine whether multinational companies are subject to additional tax.

For Thailand, the move also reflects a broader effort to align its corporate tax system with international standards while maintaining its position as an investment destination.

The global minimum tax is being implemented across a large group of jurisdictions under the OECD’s Pillar Two framework. Its application is intended to create a common floor for taxation of large multinational businesses operating across multiple countries.

Thailand’s continued implementation of the framework will require companies affected by the rules to assess their tax positions across different jurisdictions and comply with new reporting and payment requirements as the system takes effect.