How Double Tax Agreements (DTAs) Work Between Thailand & Your country

A detailed guide on pensions, dividends, interest, and foreign income tax credits under Thai tax law.

With the strict enforcement of Thailand’s foreign income remittance rules under Revenue Department Order Por. 161/2566, the primary mechanism protecting expats from double taxation is Thailand’s extensive network of Double Tax Agreements (DTAs), currently spanning over 60 countries (including the US, UK, Australia, Canada, Germany, France, and Japan).

1. The Two Primary Mechanisms of DTAs

DTAs operate primarily in two ways to ensure taxpayers do not pay full tax twice on the exact same income stream:

• Mechanism A: Primary / Exclusive Taxing Rights

  Certain types of income are designated as taxable only in the source country or only in the country of tax residence. For instance, public government pensions are almost universally taxed exclusively by the paying government.

• Mechanism B: Foreign Tax Credit (FTC) Relief

  If both countries hold taxing rights, the tax resident pays tax in the residence country (Thailand) but receives a credit for tax legally paid to the source country, up to the amount of Thai tax due on that same income.

2. Treatment of Key Income Types Under Common DTAs

3. Step-by-Step: How to Claim DTA Relief in Thailand

1. Establish Tax Residency: Obtain a Certificate of Tax Residence (RO 22) from your local Thai Revenue Department office if requested by foreign authorities.

2. Collect Foreign Proof of Payment: Secure official tax assessment notices or foreign tax return certificates showing the exact amount of tax paid on the remitted income in your home country.

3. File Annual Return (P.N.D. 90): Declare the remitted assessable income during the annual tax filing period (Jan–Mar following the tax year) and submit foreign tax paid proof to claim tax credit offsets.

Important Note on Documentation: All foreign tax documents, statements, and withholding receipts must be clearly legible and translated into Thai if requested by the local tax officer during the annual assessment.