Scope checked on 17 September 2026.<\/strong> The Emergency Decree on Top-up Tax B.E. 2567 applies to accounting periods beginning on or after 1 January 2025<\/strong>. The threshold concerns the multinational group: consolidated revenue of at least EUR 750 million in at least two of the preceding four accounting periods<\/strong>. In-scope groups must assess their exposure under the 15% global minimum-tax framework, including where a Thai company has BOI incentives<\/a>. This is a separate group-based regime; the ordinary corporate income tax and SME rates explained below continue to apply according to their own conditions. See the Revenue Department\u2019s official notice<\/a>.<\/p>\n\n\n\n Corporate tax in Thailand is a critical consideration for any business operating in the country. The corporate income tax<\/a> (CIT) rate is normally 20%, which is relatively competitive compared to other countries in the region. However, there are a number of factors that businesses should be aware of when calculating their CIT liability, such as allowable expenses and tax exemptions. For example, a company that qualifies as a small company pays nothing on its first 300,000 baht of net profit, 15% on the slice above 300,000 and up to 3 million, and 20% on anything above 3 million. The reduced rates are not automatic and the qualifying test is the part most often left out:<\/strong> the company must have paid-up capital of not more than 5 million baht on the last day of the accounting period and<\/strong> income from the sale of goods and the provision of services of not more than 30 million baht in that accounting period. A company that fails either test pays 20% on the whole of its net profit.<\/p>\n\n\n\n If you are also personally tax resident<\/a> here, see our guide to expat tax in Thailand<\/a>.<\/p>\n\n\n\n Written in March 2024 by S\u00e9bastien Brousseau, LL.B.<\/a>, B.Sc. Manager of ThaiLawOnline and permanent resident<\/a> of Thailand. Mr. Brousseau managed several companies in Thailand, and had an accountant full-time for more than 15 years. His businesses did the accounting of about 100 companies and charity associations.<\/p>\n\n\n\nTable of Contents<\/h2>