Thailand Income Tax

Thailand Income Tax. This guide explains how Thailand taxes income in practice: who is resident, what income is taxable, current personal and corporate rates, withholding obligations, the treatment of foreign-sourced income, social-security and employer duties, filing and audit risks, and high-value planning points you should know. I’ve referenced recent official/practitioner sources so you can check the numbers quickly.

1. Residency — the first and decisive test

Tax liability in Thailand depends primarily on residency. An individual is a Thai tax resident if they stay in Thailand for 180 days or more in a tax year. Residents are taxed on Thai-source income and, under current rules, on certain foreign-sourced income when it is remitted into Thailand (see section on foreign income). Non-residents are taxed only on Thailand-sourced income and generally at different withholding/final rates.

2. What is taxable — ordinary income plus more

Taxable income includes employment income (salary, allowances, benefits in kind), business profits, professional fees, rental income, interest, dividends and capital gains arising in Thailand. For residents, the tax base may include foreign income remitted into Thailand if it falls within the remittance rules (recent policy clarifications and draft reliefs affect timing and exemptions — see below). Certain social-security benefits and statutory allowances reduce taxable income.

3. Personal income tax (PIT) — progressive rates and brackets

Thailand uses progressive PIT rates with a tax-free threshold and step bands. As of the latest practitioner summaries, the personal income tax brackets are:

• 0 – 150,000 THB: exempt

• 150,001 – 300,000 THB: 5%

• 300,001 – 500,000 THB: 10%

• 500,001 – 750,000 THB: 15%

• 750,001 – 1,000,000 THB: 20%

• 1,000,001 – 2,000,000 THB: 25%

• 2,000,001 – 5,000,000 THB: 30%

• Over 5,000,000 THB: 35%.

(These are the load-bearing numbers; confirm the posting year with the Revenue Department when filing.)

4. Deductions, allowances & credits — the usual suspects

Thailand allows standard deductions and personal allowances (dependents, life-insurance premiums, retirement-contributions within limits). Employment income is often subject to payroll withholding but is reconciled annually on the personal tax return. Taxpayers can generally claim tax credits for taxes paid on foreign income to avoid double taxation where treaties or domestic rules allow.

5. Corporate income tax & global minimum rules

Thailand’s headline corporate tax regime has a statutory rate structure that depends on company size and type; however, for many companies the standard corporate income tax rate is commonly cited at around 20% for ordinary companies (special SME rates and promotional exemptions may apply). Separately, Thailand has implemented the OECD global minimum tax / top-up regime (15% top-up tax) for large multinational groups subject to the Pillar Two rules, effective from 2025 for qualifying MNEs with global turnover above the threshold. That top-up interacts with local incentives and must be modelled for cross-border groups.

6. Withholding taxes & final taxes — operational mechanics

Thailand operates a robust withholding tax (WHT) system: employers withhold on salary, and payers withhold on many cross-border and domestic payments (interest, royalties, service fees, rents, and dividends in some cases). WHT rates differ by payment type and residency of the recipient; dividends to non-residents, interest and royalties often attract withholding at statutory rates subject to treaty relief. Temporary reductions or e-filing incentives may apply in transitional periods — check current PwC/Revenue guidance when calculating gross-up.

7. Foreign-sourced income & remittance rules — a critical practical point

Historically Thailand taxed foreign income of residents only when remitted in the year it was earned or later. Since late 2024–2025 the Revenue Department has been active on clarifying/remodeling foreign income remittance rules: recent draft relief and policy notes indicate tax-free treatment for foreign income remitted in the same year or the following year under certain conditions, while later remittances may be taxable. This area has evolved quickly — treat foreign-sourced income and timing of remittances as a material planning and compliance item and get current Revenue guidance before transferring significant offshore receipts into Thailand.

8. Social security, employee levies & other payroll contributions

Employers must register employees for the Thai Social Security Fund and withhold contributions. Contribution rates can vary (normal employer and employee shares apply, with some temporary reductions noted for affected provinces or special relief periods). New workplace welfare and employee-fund initiatives have been proposed/implemented in recent years — HR should track the latest ministerial notifications.

9. Filing, deadlines & enforcement risk

Personal tax returns are generally filed annually (calendar year) with preliminary and final payment periods; employers file monthly withholding and social-security returns. The Revenue Department conducts audits and information-matching; penalties for late filing, under-payment and inaccurate disclosure can be significant. Large or unusual transactions (offshore remittances, high transfer pricing adjustments, use of incentives) attract Revenue scrutiny — keep contemporaneous documentation.

10. Practical tax-planning & compliance checklist

1. Residency review: confirm whether 180+ days test applies — this determines tax scope.

2. Model total tax (PIT + social security + WHT): run scenarios with gross-up if employer pays tax gross.

3. Foreign income timing: plan when to remit offshore income to Thailand; obtain contemporary Revenue guidance on remittance exemptions.

4. Use treaties: check double-tax treaties to reduce WHT on cross-border payments and claim credits.

5. Payroll controls: register correctly for social security, set up withholding, and keep payroll evidence for audits.

6. Large groups: model the global minimum (Pillar Two) impact for multinationals and coordinate global tax filings.

7. Document everything: bank remittances, invoices, contracts and board minutes are your strongest defense in audits.

11. Where to look for authoritative updates

Because Thai tax law and administrative practice have been actively updated (notably on global minimum tax and foreign-income remittance), use high-quality professional resources and the Thai Revenue Department notices. Good starting sources are PwC’s Thailand tax summaries (personal & corporate chapters), major local law firms’ tax alerts, and authoritative news wires for policy changes.

Bottom line

Thailand’s income-tax system is familiar (progressive PIT, corporate tax plus withholding regimes) but practical outcomes turn on residency, the timing of foreign income remittances and employer withholding compliance. Recent policy work (foreign-income remittance clarifications and the global minimum tax) makes proactive planning essential for cross-border individuals and multinationals.