Thailand Tax on Foreign Income 2026

The rule changed. Before 2024, many expats in Thailand kept their foreign income offshore or used a timing strategy to bring it in tax-free. The Revenue Department closed that door in September 2023. If you live in Thailand and earn money abroad, this page tells you where you stand.

What Changed in 2024 The Old Rule vs. The New Rule

The old "cross-year" strategy now obsolete

Until 2023, Thai tax law stated that foreign-source income was assessable only if it was remitted to Thailand in the same tax year it was earned. This created a planning strategy: earn income in year 1, leave it offshore, transfer it to Thailand in year 2. Under the old interpretation, year-2 transfers of year-1 income were not assessable.

This was not a loophole it was how many tax advisers in Thailand officially read the law, and it was never challenged by the Revenue Department. That changed in September 2023.

Revenue Department Ruling Por 161/2566 (September 2023)

The Thai Revenue Department issued Ruling Por 161/2566, which closed the cross-year strategy entirely. The ruling states that foreign-source income remitted to Thailand by a Thai tax resident is assessable in the year of remittance, regardless of when the income was earned. This applies to all income earned from 1 January 2024 onwards. There is no transition period and no grandfather provision for post-2023 income. If you file a 2024 or 2025 return and attempt to use the cross-year approach, you are filing incorrectly.

What the ruling did NOT change

• Pre-2024 savings: Money already accumulated in overseas accounts before 31 December 2023 can still be brought into Thailand without Thai PIT. The ruling applies to income earned from 2024 onwards.
• Treaty-protected income: Income types covered by a double tax agreement with Thailand remain protected under the treaty terms.
• LTR Wealthy Global Citizen / Wealthy Pensioner exemption: Royal Decree 743, issued in 2023 alongside the LTR visa framework, specifically exempts qualifying LTR holders from Thai PIT on foreign-source income. This remains in effect.

What Types of Foreign Income Are Now Assessable

For a Thai tax resident who is not protected by a treaty or RD 743, the following types of foreign income become assessable Thai PIT when remitted to Thailand in 2024 or later:

• Employment income from an overseas employer (salary, bonuses, equity grants)
• Business or self-employment income from an overseas operation
• Pension and retirement income paid from overseas
• Investment income: dividends and interest from foreign accounts
• Capital gains realised on the sale of foreign assets
• Rental income from overseas property

The key trigger is remittance transferring money into Thailand or using overseas income to pay Thai expenses. Income that remains outside Thailand is not assessed.

Pension Income US, UK, and Australian Retirees

UK pensions

The UK–Thailand Double Taxation Agreement covers pension income. Under Article 18, pensions paid from UK sources to a Thai resident are generally taxable only in Thailand. However, government pensions (paid by the UK state for government service, including military and civil service pensions) under Article 19 may be taxable exclusively in the UK. The distinction between a government pension and a private/occupational pension matters significantly. UK state pension (National Insurance) is not a government service pension it is typically assessed in Thailand under the standard rules.

US pensions

The US–Thailand tax relationship is more complicated because the treaty is limited. Private US pensions, 401(k) distributions, and IRA withdrawals are generally assessable as Thai income when remitted. US government pensions (federal, state, military) may have different treatment. See the full US–Thailand treaty guide.

Australian superannuation

Australia and Thailand have a tax treaty. Australian superannuation lump sums paid to a Thai resident are potentially assessable in Thailand, though the taxable component depends on whether the payment is from a taxed or untaxed source. Australian pensions and income streams from super funds have been an area of active discussion among Australian expats since the 2024 ruling. Professional advice specific to your fund and circumstances is particularly important here.

US Social Security Is It Taxed in Thailand?

This is one of the most commonly asked questions from American expats in Thailand, and the answer is unsatisfying: it is not clearly defined in the US–Thailand treaty.

The US–Thailand treaty does not contain a Social Security article, unlike some other US treaties (for example, the US–Germany treaty explicitly exempts German Social Security from US tax for German residents). In the absence of treaty protection, US Social Security benefits received by a Thai tax resident and remitted to Thailand could be assessable Thai income under the standard rules.

In practice, many US expats and their advisers have taken the position that Social Security benefits are excluded under the treaty or not remitted in a taxable form. The Revenue Department has not published specific guidance on US Social Security. Given this uncertainty, US retirees relying on Social Security should seek specific Thai tax advice before assuming a particular treatment applies.

Foreign Investment Income: Dividends, Interest, Capital Gains

Dividends from foreign-listed shares remitted to Thailand are assessable as Thai income. Interest earned on overseas savings accounts and transferred to Thailand is assessable. Capital gains realised on the sale of foreign assets (shares, funds, property) and remitted to Thailand are assessable Thailand does not have a separate capital gains tax, so these gains are assessed as ordinary income under the PIT schedule.

Treaty relief may be available for certain income types. For example, the UK–Thailand DTA contains provisions on dividends that may reduce Thai tax on UK dividend income. The specific treaty article and its application to your income type determines what relief, if any, is available.

Rental Income from Overseas Property

Rental income earned from property outside Thailand and remitted to Thailand is assessable from 2024 onwards. The allowable deduction for rental income is 30% of gross rental receipts (a standard deduction actual expenses cannot be claimed instead). The net amount is then added to other assessable income and taxed at the progressive rates.

If your home country also taxes your overseas rental income, a double tax treaty may provide relief. Without a treaty, you may face tax in both countries on the same income, though a foreign tax credit (paid tax in your home country offsetting Thai liability) may be available under Thai domestic rules.

Practical Steps to Assess Your Own Exposure

1. Determine if you are a Thai tax resident Count your days in Thailand for the relevant year. If you are under 180, stop here: you are a non-resident and only Thai-source income applies.
2. List all foreign income received in the year Employment, pension, investment returns, rental, business profits. Separate pre-2024 savings from post-2023 income.
3. Identify what was remitted to Thailand Bank transfers in, foreign card spending on Thai expenses, property rental payments made from overseas accounts. This is your potentially assessable amount.
4. Check for treaty protection Does your country have a DTA with Thailand? Does the treaty cover the income types you remitted? Refer to the specific treaty articles, not general summaries.
5. Check for LTR exemption If you hold an LTR Wealthy Global Citizen or Wealthy Pensioner visa, Royal Decree 743 exempts your foreign-source income. Confirm your category.
6. Calculate assessable income and apply deductions Apply the standard deductions and personal allowances, then calculate PIT using the progressive bands.
7. Get professional advice if in doubt If your income situation is complex (multiple income types, multiple countries, US dual-filing obligations), the cost of professional advice is almost always less than the cost of getting it wrong.

Double Taxation Relief Treaties and Foreign Tax Credits

Even without a treaty, Thai tax law provides a mechanism to reduce double taxation: a foreign tax credit. If you paid tax on the same income in another country, that tax may be credited against your Thai liability, subject to conditions. The credit cannot exceed the Thai tax that would otherwise be due on that income.

Where a DTA applies, its specific provisions override the domestic rules. Treaty provisions typically include a most-favoured treatment that protects the taxpayer either exclusive taxing rights in one country, or a reduced rate in the source country.

Full guide: Thailand's tax treaties country list and how to use them →