Thai Tax for Expats: Foreign Income Remittance, the LTR 17% Rate & Social Security (2026)

Thailand is one of the few Asian postings where the tax question is genuinely harder than the visa question. The visa rules are bureaucratic but legible. The tax rules changed fundamentally on 1 January 2024, were then publicly reconsidered, and the gap between what people believe and what is actually in force has widened every year since.

The headline rates are unremarkable — a 35% top band is mid-table for the region. What makes Thailand distinctive is the remittance basis: residents are taxed on foreign income only when it enters the country, which for decades made Thailand a soft landing for internationally paid executives. That softness has been removed, partially restored in proposal form, and never fully clarified. Meanwhile the social security ceiling is so low that the state scheme is close to irrelevant to an expat package, and the real retirement vehicle is the employer’s provident fund.

This article sets out what is in force for the 2026 tax year, with the baht figures, the form numbers and the deadlines — and flags clearly where something is still only a proposal.

Who counts as a Thai tax resident, and does the 180-day rule really work like that?

Section 41 of the Revenue Code defines a resident as a person present in Thailand for an aggregate period of 180 days or more in a tax year. The tax year is the calendar year, with no option to change it. The word that matters is aggregate: days are added up across every separate entry, so four two-month trips make you resident just as surely as one continuous stay. There is no concept of short-term residence in Thai tax law and no concessionary regime for people who are "only here for a project".

The consequences split cleanly:

• Resident. Taxed on Thai-source income wherever it is paid, plus foreign-source income brought into Thailand.
• Non-resident. Taxed on Thai-source income only. Foreign income is entirely outside the net, remitted or not.

Two traps follow. First, residence is tested year by year, not on a rolling basis — a 175-day year is a non-resident year even if the 12 months either side are resident years. Second, source and residence are separate questions. Income from employment exercised in Thailand is Thai-source and fully taxable even if the contract is foreign, the payroll is foreign and the money never touches a Thai bank. The Revenue Department’s position is explicit: employment income is taxed on services performed in Thailand regardless of whether payment is made within or outside the country, and there are no concessions for foreigners or short-term residents. If you are structuring an assignment, the first thing to settle is where the work is physically done, not where the payslip is issued — a point worth reading alongside how Thai employment contracts and labour law actually bind the employer.

What actually changed on foreign income remitted into Thailand?

For most of Thailand’s modern tax history, section 41 paragraph two was read narrowly: a resident paid tax on foreign income only if it was brought into Thailand in the same calendar year it was earned. Earn a bonus offshore in 2022, leave it in a Singapore account, remit it in 2023, and it arrived untaxed. That was not a loophole in the pejorative sense — it was the settled administrative reading, supported by departmental rulings, and it was the backbone of every expatriate structuring exercise in the country.

It ended with two instructions:

• Por. 161/2566, issued 15 September 2023, reinterprets section 41 paragraph two so that foreign-source assessable income is taxable when remitted to Thailand, whether in the year it was earned or in any later year. It cancels the earlier rulings that said otherwise.
• Por. 162/2566, issued 20 November 2023, adds the transitional limit: the new reading does not apply to income earned before 1 January 2024.

The instructions came into force for assessable income brought into Thailand from 1 January 2024 onwards. The combined effect for 2026 is simple to state and uncomfortable to live with: money earned offshore from 2024 onwards carries a permanent Thai tax contingency that crystallises the moment it is remitted, in any year, at the progressive resident rates applying in the year of remittance.

The Revenue Department published a Q&A clarification, third edition, on 23 January 2024. The useful points:

• Income earned before 2024 is not taxed when remitted in 2024 or later.
• Income earned in a year in which you were not a Thai resident is not taxed on remittance — a genuinely valuable rule for people who arrive mid-career.
• Accumulated savings built up during non-resident years can be brought in without charge.
• Sending your own money abroad and bringing it back is not assessable income.
• Remittances are converted at the exchange rate on the date of remittance.
• Foreign tax paid can be credited where an applicable double tax agreement allows it.

The 2025 relaxation: what is actually in force

Since 2025 there has been sustained public discussion of a relaxation that would exempt foreign-source income brought into Thailand in the calendar year it is earned or in the following calendar year — restoring something close to the pre-2024 position for prompt remittances while still catching long-parked offshore funds. The policy logic is clear enough: Por. 161 discouraged residents from repatriating money at all, which was never the intention.

State the status honestly, because a great deal of bad advice turns on this point. As of October 2026, the professional guides maintained by the major firms — including PwC’s Thailand individual tax guide, last reviewed on 24 August 2026 — still set out the Por. 161 rule as the operative law, describing foreign income earned from 1 January 2024 as taxable when remitted in the same or any later tax year, and list no enacted exemption for same-year or following-year remittances. Treat the relaxation as a proposal under consideration, not as law. If it has since been gazetted as a Royal Decree, that decree is the authority — not a news article, not an adviser’s newsletter, and certainly not this page.

What will you pay on a Thai salary in 2026?

Resident rates run on eight bands, set by the Revenue Code Amendment Act (No. 44) and unchanged in structure since the 2017 tax year. They apply to net income — assessable income after expense deductions and after allowances.

Two features are worth noting against regional comparators. The 35% top rate does not bite until net income passes THB 5,000,000 — a genuinely high threshold, and the reason senior Thai packages are less punitive than the headline rate suggests. But the exempt band stops at THB 150,000, so junior and mid-level staff start paying earlier than in several neighbouring jurisdictions.

A resident aged 65 or over gets an exemption on assessable income up to THB 190,000, which matters for the retiree-consultant population. Filing is not required at all where employment income is THB 120,000 or less for a single filer, or THB 220,000 or less for a married filer, with the equivalent thresholds for other income being THB 60,000 and THB 120,000.

Non-residents face the same progressive scale on Thai-source employment income — there is no flat expatriate rate — but lose most family allowances, since spouse, child and parental reliefs are tied to dependants in Thailand. Other Thai-source payments to a non-resident individual are generally caught by flat withholding: 15% on service and agency fees, rights and royalties, interest, capital gains, rental and professional fees, and 10% on dividends and profit shares.

Which deductions and allowances can an expat actually use?

Thailand runs a two-stage reduction: an expense deduction against each category of income, then personal allowances against the total. For employment income the expense deduction is 50% of assessable income, capped at THB 100,000. The cap is the point. Above THB 200,000 of annual salary — which is every expat package in the country — the deduction is a flat THB 100,000 and nothing more. Employees cannot claim actual business expenses as an alternative.

The allowances then do the real work, and most of them are available to a foreign resident on the same terms as a Thai national.

The single hard constraint is the THB 500,000 combined retirement cap. Provident fund contributions, qualified pension insurance, RMF, Super Savings Fund, the National Savings Fund and the civil servant and teachers’ funds all compete for the same THB 500,000 of annual relief. A high earner contributing meaningfully to an employer provident fund will often have little headroom left for RMF or SSF, and the usual mistake is to buy both and discover the second one is dead weight.

The Thai ESG fund sits outside that cap and is the most under-used relief in the expat population — 30% of assessable income up to THB 300,000 a year, with a five-year holding period for units bought in the enhanced 2024 to 2026 window. On a THB 3,000,000 salary that is a further THB 300,000 of relief at a 30% marginal rate, worth THB 90,000 of tax. Note the end date: 31 December 2026 closes the enhanced window as currently legislated.

Can you really pay 17 percent, and who qualifies?

Three regimes give a concessionary flat personal rate, and none of them is the Board of Investment.

The LTR visa, 17% for Highly-Skilled Professionals

The Long-Term Resident visa, administered by the BOI through ltr.boi.go.th, is a ten-year visa in four categories: Highly-Skilled Professionals, Work-from-Thailand Professionals, Wealthy Global Citizens and Wealthy Pensioners. Spouses and children under 20 can hold dependent visas. The Highly-Skilled Professional category carries a flat 17% personal income tax rate — against a 30% or 35% marginal rate for a senior hire, that is the difference between a competitive offer and an uncompetitive one.

The conditions are narrower than the marketing suggests:

• Role. You must be a professional or expert in a targeted industry, working for a business entity, higher education institution, research centre or specialised training institution in Thailand, or for a Thai government agency.
• Income. Average personal income of at least USD 80,000 a year over the past two years. Thai government employees are exempt from the income test.
• Reduced income route. Average income between USD 40,000 and USD 80,000 is acceptable with additional proof — typically a master’s degree or higher in science and technology.
• Contract or expertise. A contract with a Thai or foreign company in a targeted industry, or demonstrated expertise in a field the BOI specifies.
• Financial safeguard. Health insurance of at least USD 50,000, or current Thai social security coverage, or at least USD 100,000 held in your own bank account for twelve months or more.

The qualifications must be maintained for the life of the visa, not merely satisfied at application. An employer planning around the 17% rate should model what happens if the employee’s package or the company’s activity drifts out of the targeted-industry definition mid-assignment — and should understand how the LTR interacts with the ordinary permit route, which is covered in the Thailand work visa guide for expats.

The Eastern Economic Corridor: also 17%

The Eastern Economic Corridor Act of 2018 grants a personal income tax reduction to employees with special knowledge or ability working for, or operating, a business in designated EEC zones. Qualified expatriates and Thai employees are taxed at a flat 17% on income from working for companies carrying on target activities within the Corridor, and the benefit extends to spouses, parents and children.

International Business Centre: 15%

Expatriate full-time employees of an International Business Centre, or of an International Trade Centre business, may be taxed at 15%. Where the company also runs other businesses, IBC or ITC revenue must be at least 70% of total revenue for the regime to hold. This is the lowest headline personal rate available in Thailand, and the least used, because the corporate qualification is demanding.

And what BOI promotion does not do

BOI promotion is a corporate instrument. It delivers corporate income tax exemptions and reductions, import duty relief and research-and-development benefits, and it delivers visa and work permit facilitation for foreign experts through the BOI’s own channel rather than the standard Ministry of Labour route. It does not alter the expatriate’s personal income tax rate by a single baht. Any package modelled on the assumption that "we’re BOI-promoted so the expat pays less tax" is modelled wrong, and the correction usually surfaces in March of the following year.

What does Thai social security buy you, and why is it so cheap?

The Social Security Fund, run by the Social Security Office (Samnakngan Prakan Sangkhom), is compulsory for employees — including foreign employees working legally under a work permit. Contributions are 5% of monthly wages from the employee and a matching 5% from the employer, with the government contributing a further matching amount.

The rate is unremarkable. The ceiling is the whole story. The maximum levy is THB 875 per employee per month on each side, which works back to a contributory wage ceiling of THB 17,500 a month — raised from the long-standing THB 15,000 ceiling that produced a THB 750 cap.

For an employer, that is the entire statutory social cost of a Thai hire: THB 10,500 a year per employee, whether the salary is THB 20,000 a month or THB 500,000. Compared with a European employer burden of 20% to 40% of gross with no meaningful ceiling, Thailand is close to free. This is a large part of why total employment cost in Thailand is so much lower than the salary comparison alone suggests — the arithmetic is set out in the Thailand relocation and cost-of-employment breakdown.

What the fund actually pays for is the statutory benefit package: non-work-related sickness and injury, maternity, invalidity, death, child allowance, old-age pension or lump sum, and unemployment. Work-related injury and illness sit outside the Social Security Fund entirely — they are covered by the separate Workmen’s Compensation Fund, which the employer funds alone.

The gap between coverage and expectation is where expat packages get built. Benefits are calibrated to a THB 17,500 contributory wage, which means the sickness and maternity benefits replace a fraction of an expat salary, and the public hospital network the scheme routes you to is not where an international hire expects to be treated. Hence the near-universal private medical layer: an international plan sitting on top of the state scheme, with the employee’s own health insurance premium relief capped at THB 25,000 a year inside the THB 100,000 life-and-health cap. The old-age element is similarly thin — a pension built on a THB 17,500 base is not a retirement plan.

The provident fund is the real retirement vehicle

Thailand’s substantive retirement saving happens in the employer’s registered provident fund, established under the Provident Fund Act and governed by a fund committee with employee representation. Employee contributions attract relief at 15% of assessable income up to THB 500,000, inside the THB 500,000 combined retirement cap. Employer contributions to a registered fund are not taxed on the employee as they are made, and benefits received from a registered provident fund on retirement are exempt from personal income tax where the statutory conditions — principally age and length of membership — are met.

Two points for the mobile employee. The exemption on withdrawal depends on meeting those conditions, so an expatriate who leaves after three years and cashes out does not get the same treatment as a career employee retiring at 55 with five years of membership. And a provident fund is a Thai-domiciled pot: check how your home jurisdiction treats it before you load it, because the relief you gain in Bangkok can be clawed back elsewhere.

How does Thai payroll reporting work, and what are the deadlines?

Thailand runs a conventional withholding system with a light annual reconciliation.

• Monthly withholding (PND 1). The employer withholds personal income tax from salary at the progressive rates under section 50(1) of the Revenue Code, grossing the employee’s projected annual position down to a monthly deduction. The tax withheld must be remitted within seven days of the end of the month of payment. Online filing attracts the Revenue Department’s standing e-filing extension, as the annual return does.
• Annual withholding reconciliation (PND 1 Kor). A year-end summary of everything withheld and remitted per employee, filed after the close of the tax year and reconciled against the employees’ own returns. Mismatches here are the most common trigger for a Revenue Department query on an expat file.
• Annual return (PND 91). Individuals with employment income only file PND 91. Those with other categories of income file PND 90. The deadline is 31 March of the following year for paper filing and 8 April for online filing — the e-filing extension is eight days, and it is the simplest free extension in Asian tax compliance.
• Half-year return (PND 94). Individuals with business, professional, rental or most other non-employment income file a return for the first six months by 30 September and pay the tax due. Pure salary earners are outside this.
• Spouses. Each spouse may file separately or jointly. Separate filing is usually better once both are earning, because the progressive bands apply twice.

Withheld tax is creditable against the annual liability, and the balance is payable when the return is filed. Residents who have had tax correctly withheld all year and claim no extra reliefs often file a near-nil return — but the filing obligation still exists, and the employer’s obligations do not stop at the payslip, as set out in the guide to employer compliance when hiring expats in Thailand.

What happens on termination, under a treaty, and when you leave?

Severance pay and the separate computation

Statutory severance is partly exempt. Amounts paid on involuntary termination are exempt up to the last 400 days’ pay, capped at THB 600,000 — a figure that tracks the maximum statutory severance entitlement for long-service employees. Anything above that is taxable employment income.

The more valuable relief is the separate computation under section 48(5) of the Revenue Code. Where the employer pays a lump sum on termination calculated by reference to length of employment, under rules set by the Director-General, the taxpayer may elect to tax that lump sum separately rather than aggregating it with the year’s other income. Under the separate computation, the expense deduction is THB 7,000 per year of employment (capped at the amount of the lump sum itself), and a further 50% deduction is allowed against the remainder before the progressive rates apply. For a gratuity paid alongside a pension, the per-year figure is THB 3,500.

The arithmetic matters. A terminated employee with 12 years’ service receiving a THB 2,400,000 lump sum deducts THB 84,000 for service, then 50% of the THB 2,316,000 remainder, leaving THB 1,158,000 to be taxed on the scale from the bottom band up — instead of stacking the whole THB 2,400,000 on top of a salary already in the 30% band. The election is not automatic. It must be claimed, and it is routinely missed.

Treaty relief and the dependent-personal-services trap

Thailand has double tax agreements with 61 jurisdictions, including every major source of expatriate labour. The hard rule to understand is the credit mechanism: foreign taxes cannot be credited against Thai tax unless a treaty permits it. Thailand grants no unilateral credit to individuals. If you are resident in Thailand and remit income from a non-treaty country that has already taxed it, you can be taxed twice with no domestic relief.

For short-term assignees, the operative provision is the dependent personal services article — the employment income article that appears in substantially the same form in most of Thailand’s treaties. It typically relieves employment income from Thai tax where all of three conditions hold: presence in Thailand of 183 days or less in the relevant period, remuneration paid by an employer who is not a resident of Thailand, and the remuneration not borne by a permanent establishment of the employer in Thailand.

The trap is the third condition, and sometimes the second. A short-term assignee passes the day count comfortably, assumes the exemption applies, and overlooks that the cost of their time has been recharged to the Thai entity. Once the Thai entity bears the remuneration, the article fails and the income is taxable in Thailand from day one — with no withholding having been operated, and interest and penalty running from the original deadline. Intercompany recharge policy is a tax position, not an accounting convenience. Check the specific treaty, because wording and reference periods differ.

The departure tax myth

There is no Thai exit tax. Leaving Thailand does not trigger a deemed disposal, a departure charge or a tax on unremitted foreign income. The "departure tax" travellers remember is the airport passenger service charge, bundled into the ticket price and collected by the airline — a fee, not a tax on income.

The partial truth behind the myth is the Revenue Code’s tax clearance certificate regime, which requires certain persons to obtain clearance before departing Thailand. The Director-General’s notification confines it to a narrow group: people with outstanding tax arrears, foreign public performers with Thai income, and people responsible for paying tax on behalf of a non-resident company carrying on business in Thailand. An ordinary expatriate employee leaving at the end of an assignment, with tax properly withheld, does not need one. What you do need is to file for your final part-year — leaving in August does not cancel the following March’s return, and an unfiled final year is the most common reason a returning expatriate finds an old Thai liability waiting.

Frequently Asked Questions