Why the date matters
Thai personal income tax is calculated on the calendar year. Your 2026 return, filed between January and early April 2027, can only deduct what you paid or invested between 1 January and 31 December 2026. A fund bought on 2 January 2027 counts for 2027, not for 2026.
Check your deductions with a tax professional
40 minutes by video or phone, before you invest.
The deductions still in your hands this year
| Deduction | 2026 limit | Main condition | Act before |
|---|---|---|---|
| Thai ESG and Thai ESGX funds | 30% of assessable income, THB 300,000 maximum | Keep the units 5 years | Your fund's last 2026 dealing day |
| RMF (retirement mutual fund) | 30% of assessable income, within a THB 500,000 retirement cap | Hold until 55 and at least 5 years | 31 December 2026 |
| Life insurance with a Thai insurer | THB 100,000 | Policy of 10 years or more | Premiums paid in 2026 |
| Health insurance for you | THB 25,000, inside the THB 100,000 insurance cap | Thai insurer | Premiums paid in 2026 |
| Health insurance for your parents | THB 15,000 | Parents' conditions apply | Premiums paid in 2026 |
| Home loan interest | THB 100,000 | Loan for your home, Thai lender | Interest paid in 2026 |
Your employer withholds Social Security contributions from your salary, and you claim them as a deduction on your return: for 2026 the maximum is THB 10,500 (THB 875 a month), up from THB 9,000.
Thai ESG and Thai ESGX funds
This is the largest lever for many employees. For 2026, the deduction is up to 30% of your assessable income with a maximum of THB 300,000, and Thai ESG and Thai ESGX count together. You must keep the units for 5 years, counted day by day. Fund managers announce a 2026 subscription window that closes before 31 December (one manager lists 5 January to 30 December 2026), so do not wait for the last day.
From 2027, the rules are expected to become less generous unless the government extends them. That makes 2026 a good year to use the full limit if the investment suits you.
RMF and the THB 500,000 retirement cap
An RMF can be deducted up to 30% of your assessable income. It shares a THB 500,000 ceiling with your provident fund, pension insurance and other retirement products. You must hold the RMF until age 55 and for at least 5 years, otherwise the tax saved is clawed back with a surcharge. An RMF makes sense if you expect to stay in Thailand for many years.
A worked example
Somchai is a Thai tax resident with a salary of THB 1,800,000 in 2026. He paid the maximum Social Security of THB 10,500.
| Without investing | With THB 200,000 in Thai ESG | With Thai ESG and THB 200,000 in an RMF | |
|---|---|---|---|
| Taxable income | THB 1,629,500 | THB 1,429,500 | THB 1,229,500 |
| Thai tax 2026 | THB 272,375 | THB 222,375 | THB 172,375 |
| Saving | THB 50,000 | THB 100,000 |
At a 25% marginal rate, every THB 100,000 deducted saves THB 25,000 of tax. The saving depends on your own rate: on a THB 600,000 salary, the same Thai ESG investment would save much less. Use the calculator to see your own figures.
See what you could save
Free calculator with the 2026 rate bands.
If you have income abroad: plan your transfers
Foreign income earned since 1 January 2024, in a year in which you were a Thai tax resident, is taxed when it is brought into Thailand. Income earned before 2024 is not taxed when you bring it in, if you can prove when it was earned. Before your next transfer:
- Keep statements that show where the money comes from and when it was earned.
- Separate savings from before 2024 from income earned since 2024.
- Check whether a tax treaty or a foreign tax credit applies to your country.
The proposed exemption for income brought in within the year it is earned or the next year is still a draft, not law. Do not plan your 2026 transfers on it.
What to gather in January
- Your 50 Tawi certificate from each employer.
- Annual certificates from your funds, insurers and bank (they are usually sent in January).
- Statements for any money brought from abroad in 2026.
Not sure what applies to you?
Many deductions depend on facts: your residence status, your visa, where your income comes from. A 40-minute consultation before the end of the year can show which deductions apply to you.
Check your deductions with a tax professional
40 minutes by video or phone, before you invest.
Your checklist before 31 December 2026
- Check that you are a Thai tax resident for 2026 (180 days or more in Thailand).
- Estimate your 2026 tax and your top rate with our calculator: the higher the rate, the more each deduction saves.
- Choose your Thai ESG or RMF amount and buy before your fund's last dealing day of 2026, not on 31 December.
- Pay the insurance premiums and home loan interest due in 2026 and keep the annual certificates.
- Before moving money from abroad, keep statements that show when it was earned (before or since 2024).
- In January 2027, collect your 50 Tawi and the certificates from your funds, insurer and bank.
Questions we are asked every December
Can I buy Thai ESG in January 2027 and deduct it for 2026?
No. The deduction follows the calendar year of the purchase. A purchase in January 2027 counts for your 2027 return.
Do foreigners get the same deductions as Thai nationals?
A foreigner who is a Thai tax resident, meaning 180 days or more in Thailand in 2026, generally has the same allowances. Non-residents have restrictions, so check your status first.
Is SSF still deductible in 2026?
No. The SSF deduction ended after the 2024 tax year. Thai ESG and RMF are the funds that remain deductible in 2026.
What happens if I sell my Thai ESG units early?
If you sell before the 5-year holding period, the tax saved must be repaid with a surcharge. Only invest money you can leave in place.
Official sources
- Revenue Department: personal income tax allowances
- Krungsri Asset Management: Thai ESG and Thai ESGX 2026 conditions
- Revenue Department: personal income tax rates
- Revenue Department: guide to tax on income from abroad (EN)
- ThaiLawOnline: remittance exemption status tracker (September 2026)
- Social Security Office
Sources verified on 4 October 2026. This page explains general rules; it does not replace advice on your own facts.
Written and checked by the VB & Partners tax team in Bangkok, who prepare and file Thai returns for foreign residents every year. Meet the team →
