Thailand corporate tax law treats capital gains income that's derived by entities as normal assessable income subject to corporate income tax. 

That is, as Thailand has no separate capital gains tax law, capital gains income is just one of the 'all income' types Section 65 of Thailand's Revenue Code subjects to corporate income tax.

A summary of the taxation of capital gains income for resident and non-resident corporate entities is as follows:

Resident Corporate Entities

For capital gains income derived from sales of assets, investments, property, shares etc

Corporate income tax on the amount of the capital gain

Resident corporate entities need to note the capital gains amount is subject to a 'market price' provision in the tax code, which prescribes that if the sales price is lower than the market price, tax audit officers have the power to adjust the sales price to the market price and re-assess tax based on the market price.

Non-Resident Corporate Entities

For capital gains income derived from sales of assets, investments, property, shares etc

15% withholding tax on the amount of the capital gain

Non-resident corporate entities need to note that the amount of capital gains is subject to the 15% withholding tax prescription in the local Thailand tax law that payers in Thailand are required to deduct from the amount of capital gains paid.

But the 15% withholding tax under the local Thailand tax law may be reduced or exempted under a Thailand Double Tax Treaty, and it is therefore important for non-resident corporate entities to ensure payers in Thailand deduct the rate of withholding tax prescribed in applicable Double Tax Treaties.

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