Tax Residency in Thailand: When It Applies
Thailand taxes you as a resident based on presence, not citizenship. If you stay in Thailand more than 180 days in a calendar year (1 Jan–31 Dec), or if you're a Thai national, you're considered a tax resident and must file a Thai tax return (even if you earn nothing).
Key rule: Only income earned in Thailand is taxed. Foreign-sourced income (US salary deposited to US bank, UK dividends, overseas rental income) is NOT taxed unless it's remitted to Thailand.
If you earn foreign-source income and don't bring it into Thailand, you owe no Thai tax. If you remit it to Thailand, you declare it as Thai-source income and pay tax at your marginal rate. Most working expats have Thai-source income (local employment, freelancing with Thai clients) and must file annual TM.86 form by 31 March each year.
Thailand Income Tax Rates (2026)
Progressive scale. After deductions, only taxable income above minimum threshold is taxed:
| Annual Taxable Income (THB) | Tax Rate | Cumulative Tax (example) |
|---|---|---|
| 0–150,000 | 0% | ฿0 |
| 150,001–300,000 | 5% | ฿7,500 |
| 300,001–500,000 | 10% | ฿27,500 |
| 500,001–750,000 | 15% | ฿65,000 |
| 750,001–1,000,000 | 20% | ฿115,000 |
| 1,000,001–2,000,000 | 25% | ฿365,000 |
| 2,000,001–5,000,000 | 30% | ฿1,265,000 |
| 5,000,001+ | 35% | Calculated individually |
Example: Annual income ฿1,500,000 (gross) → Deductions ฿350,000 (insurance, expenses) → Taxable ฿1,150,000 → Tax ฿215,000 (effective ~14% on gross).
Filing Your Tax Return
Key Deadlines & Forms
- Form TM.86: Annual income tax return (must file if resident or earning Thai-source income).
- Deadline: 31 March each year for the prior calendar year (e.g., 2025 taxes due 31 March 2026).
- Filing location: Revenue Department (Thai: สรรพสถานสรรพากร) at your registered address. Phuket Town: Phuket Rd, opposite Lardprao, 076-212182.
- Filing method: In person, by mail, or via CPA (most expats use this route).
What Deductions Apply?
You can claim the following before calculating tax:
- Personal exemption: ฿40,000–50,000 (standard for all residents)
- Health/accident insurance: 100% of premiums up to ฿5,000/year (expat health insurance counts)
- Contributions to Thai funds: 5% to National Savings Fund, etc.
- Income splitting (married): Can split income with spouse if filing jointly
- Business expenses (if self-employed): Costs directly related to earning income (office rent, equipment, subcontractors — requires documentation)
- Donations: Up to 2% of taxable income to registered charities
Most working expats don't qualify for major deductions beyond personal exemption and insurance, so effective tax rate varies 12–18% on gross income.
Foreign-Source Income Rule (2024 Change)
Major change in 2024: Thailand now taxes foreign-source income in the year it's earned if you're a Thai tax resident, UNLESS you have a foreign tax treaty exemption or the income is already taxed abroad.
Practical impact on expats:
- US expats: Must report worldwide income to USA anyway (FATCA/citizenship tax). Generally claim Thailand taxes paid as foreign tax credit, so no double tax. BUT if Thailand tax rate is lower than US rate, you still owe US tax on difference.
- UK/EU expats: Only declare Thailand-source income to HMRC/home country. Foreign-source income not taxed in Thailand if NOT remitted. If remitted to Thailand, you must declare it both in Thailand and home country.
- Australian expats: Different rules; consult accountant.
Bottom line: If you're salaried locally in Phuket (Thai-source), you file TM.86 and pay Thai tax. If you're paid by foreign company (foreign-source), only declare/pay Thailand tax if money enters a Thailand bank account. Safest approach: work with accountant (see below).
Hiring a CPA / Tax Accountant
Why Use One?
- Navigates foreign-source income rules correctly (saves ฿10,000–50,000 in tax mistakes)
- Prepares TM.86 form, ensuring all deductions claimed
- Handles filing deadline, minimizes penalties
- Advises on visa implications (work permit, tax residency)
- Keeps records organized for future tax audits
Cost & How to Find One
Typical costs in Phuket:
- Simple filing (single person, salaried, standard deductions): ฿2,000–4,000 per year
- Self-employed / freelancer (multiple income sources): ฿4,000–8,000 per year
- Ongoing accounting (monthly bookkeeping): ฿3,000–6,000/month
Finding a CPA in Phuket:
- Expat networks: Ask in Phuket Expat Facebook groups — many expats recommend their accountant (word-of-mouth is best)
- International accounting firms: Bigger firms in Bangkok with Phuket reps (e.g., EY, Deloitte, KPMG) — expensive but thorough
- Local Thai CPAs: List available from Revenue Department or Thai Chamber of Commerce. Most speak English to non-fluent level; recommend checking references
What to Ask a CPA Before Hiring
- ✅ Years of experience with expat clients
- ✅ How they handle foreign-source income calculations
- ✅ Whether they can integrate with your home country taxes (especially US FATCA)
- ✅ Fee structure (hourly vs fixed, any hidden costs?)
- ✅ Timeline for filing (ideally complete by mid-Feb for early deadline buffer)
Frequently Asked Questions
Legally complex. If you stay <180 days in a calendar year, you're NOT a tax resident, so Thailand doesn't claim tax. BUT if you stay >180 days, you become resident and must file TM.86 (including foreign-source income). Keep dated entry/exit stamps to prove <180 days. That said, working on Tourist visa is illegal (violates work permit rules). Safe option: switch to LTR visa or Non-B work permit, then properly file taxes.
If self-employed or freelance, yes — business losses offset income, reducing taxable amount. If salary + side business loss, you can net them. Must keep receipts/documentation. Salaried employees with no other income cannot claim losses.
Late filing penalties: 5–10% of unpaid tax. If tax is ฿100,000, late penalty could be ฿5,000–10,000 per month. File late? Contact CPA immediately to minimize penalty. Most CPAs can request deadline extension (usually granted).
Yes, if earned in Thailand or remitted to Thailand. Interest on Thai savings accounts, dividends from Thai stocks, rental income from Thai property — all taxable. Foreign dividends/interest not taxed unless remitted to Thailand.
Required. Tax evasion can result in fines (100–200% of unpaid tax), criminal prosecution (rare for small amounts), and loss of visa sponsorship. For expats, most employers withhold tax automatically. Stay compliant — fines are expensive and visa complications not worth it.