Paying Thai Income Tax (PND 90/91) as an Expat in Thailand

Home - Finance - Paying Thai Income Tax (PND 90/91) as an Expat in Thailand BANGKOK – Many expats struggle to determine whether they’re Thai tax residents, whether foreign income becomes taxable after it reaches Thailand, and whether they should file PND 90 or PND 91. The answer depends on details such as your days in Thailand, the type of income you received, and when you earned and remitted it. This guide focuses on the 2025 tax year, filed in 2026, and explains who must file, how the 180-day residency test works, when remitted foreign income may be taxable, how to calculate and pay tax online, and what can happen if your return is late. It also covers PND 90 and PND 91 tax returns, while noting that deadlines and rules can change. Use this as general information, not personal tax advice, then start by checking your Thai tax residency status. Thailand’s personal income tax applies to assessable income, meaning income the Revenue Code recognizes for taxation. It can include salary, freelance fees, business profits, rent, interest, dividends, pensions, and certain foreign earnings. The Revenue Department’s personal income tax guidance explains how Thai-source and foreign-source income can fall within the tax system. You generally become a Thai tax resident when you spend 180 days or more in Thailand during a calendar year, from January 1 through December 31. The days do not need to be consecutive. Residency depends on your physical presence, not your visa type, nationality, work permit, or whether you own a home in Thailand. A tourist who stays long enough can meet the test, while a long-term visa holder who spends fewer than 180 days may not. However, tax residency and filing obligations are separate questions. Even a nonresident may need to report Thai-source income. Thai residents generally pay tax on Thai-source income and may also owe tax on foreign-source income brought into Thailand. A foreign bank account or overseas employer does not automatically remove Thai tax obligations. Thai-source income usually comes from work, business activity, property, or services connected with Thailand. Foreign-source income comes from activity or assets outside Thailand, such as overseas employment, foreign investments, or rental property abroad. Under the current rule, foreign income earned on or after January 1, 2024 may become assessable when a Thai tax resident remits it to Thailand. That can apply even when the money arrives in a later tax year. Foreign income earned before January 1, 2024 is generally treated differently under current Revenue Department guidance. Keep bank statements, travel records, payslips, investment statements, and evidence showing when you earned and transferred funds. These records help separate income from savings or capital. Tax treaties may change how particular income is taxed, but you should not assume a treaty applies without checking its terms. If you have salary only, PND 91 may fit; other assessable income usually requires PND 90. The correct Thai tax return depends on the type of income you received during the year, not simply your job title or whether you are an expat. PND 91 is limited to employment income under Section 40(1), while PND 90 covers broader or mixed income. Use PND 91 when your only assessable income comes from employment under Section 40(1). This generally includes salary, wages, bonuses, and similar employment income. The Revenue Department describes PND 91 as the return for taxpayers with only Section 40(1) employment income. You can review the official PND 91 form details before filing. For example, an employee who receives one monthly salary from a Thai employer and has no rental, freelance, investment, or business income would normally file PND 91. The same applies if the employer already withheld income tax during the year. However, withholding tax does not always settle your final annual liability. Your total income, deductions, allowances, and tax credits may produce additional tax or a refund when you file the annual return. PND 90 is the broader annual return for taxpayers with income beyond employment-only Section 40(1) income. It can cover business profits, freelance fees, rent, interest, dividends, pensions, and capital gains where applicable. It also applies when you combine salary with another assessable income type. An employee who earns a salary and rents out a condominium, for example, would generally use PND 90. The same is true for an employee who receives freelance design fees, overseas pension income, or reportable investment income. RSM Thailand’s PND 90 and PND 91 guidance explains this employment-only versus mixed-income distinction. PND 94 is separate. It is a midyear return for certain non-employment income earned during the first half of the year, such as qualifying business, professional, rental, or freelance income. It does not replace the annual PND 90 or PND 91 filing. If you have mixed foreign income, stock sales, pensions, or an unclear income category, ask the Revenue Department or a qualified Thai tax adviser before submitting your return. Your Thai personal income tax depends on taxable income, not your gross pay alone. Start with assessable income, subtract permitted expense deductions, remove personal allowances and eligible deductions, then apply the progressive tax rates. You can review the Thai personal income tax rate table before preparing your return. For the 2025 tax year, the rates are: These rates apply only to the income within each band. Reaching the 20% bracket does not make all your income taxable at 20%. Common reliefs can include the 60,000 THB personal allowance, a qualifying spouse allowance, child allowances, social security contributions, approved life or health insurance, retirement funds, mortgage interest, and qualifying donations. Employment income may also receive a permitted expense deduction, generally 50% up to the applicable maximum. The limits and conditions can change, so confirm each amount for the relevant tax year. Thailand’s tax changes for expats may also affect how you review foreign income and available reliefs. If you earned income in another currency, convert it into Thai baht using an accepted exchange rate. Use the same method consistently and retain the exchange-rate records with your bank statements and income documents. Assume these fictional figures: The calculated tax is 155,000 THB: 7,500 THB at 5%, 20,000 THB at 10%, 37,500 THB at 15%, 50,000 THB at 20%, and 40,000 THB at 25%. After crediting withholding, the remaining balance is 15,000 THB. Filing becomes easier when you gather your records before opening the online form. Use the Thailand tax filing guide to check the correct form, documents, and filing steps, then work through the checklist below. Keep digital copies of these records: The Revenue Department provides tax-year forms and attachments. If you received a qualifying lump-sum termination payment an