Thai Tax ID & Filing for Foreigners: Who Actually Must File

Thai Tax ID & Filing for Foreigners: Who Actually Must File

You must file a Thai personal income tax return if you're a tax resident (180+ days in Thailand in a calendar year) who remitted assessable foreign income, or if you earned Thai-source income, or if your assessable income cleared roughly ฿120,000 ($3,640) single / ฿220,000 ($6,670) couple for non-employment income. Filing is required even when the tax owed comes out to zero. The paper deadline is 31 March 2026; e-filing gets you until 8 April 2026.

That last point trips up more expats than anything else in Thai tax. A zero tax bill doesn't mean no paperwork; the filing obligation and the payment obligation are separate, and the Revenue Department has been cross-checking immigration and banking data since the 2024 remittance rule took effect.

Quick answer: the filing checklist

• File if: resident ≥180 days AND remitted foreign income, OR any Thai-source income, OR assessable income over the threshold — even at zero tax owed.
• Thresholds (non-employment income): commonly cited ฿120,000 single / ฿220,000 couple; employment-only income uses lower bands in some guidance (~฿60,000/฿120,000) — figure depends on income category.
• TIN required: once Thai-source income or a remittance creates an obligation — guidance cites a ~60-day registration window.
• Deadlines: paper return 31 March, e-filed return 8 April (2025 tax year, filed 2026).
• Live rule: remittance-based taxation under Por 161/162 (since 1 Jan 2024) — NOT repealed or replaced. See the foreign-income tax status tracker.
• Bank account not required: the filing obligation runs on income and residency, not where you bank.

The three triggers that force a filing

Thailand's rule is simpler than it looks once you separate the three paths that create an obligation.

1. Resident + remitted foreign income. Spend 180 days or more in Thailand in a calendar year (days need not be consecutive) and you become a Thai tax resident under Section 41 of the Revenue Code. A resident who then remits foreign-sourced income earned in 2024 or later — savings, pension, dividends, rental income from abroad — must file, regardless of what year that income was actually earned. This is the Por 161/2566 and Por 162/2566 regime, in force since 1 January 2024. It was never repealed; a 2025 "two-year exemption" relief draft lapsed when parliament dissolved ahead of the 8 February 2026 election, and no post-election source confirms whether the new government will revive it. Read the 180-day residency rule breakdown before you count days.

2. Thai-source income, any residency status. Salary from a Thai employer, rental income from a Thai property, freelance work paid by a Thai client, or business profit earned inside Thailand triggers a filing obligation no matter how many days you spent in the country. Non-residents are only ever taxed on Thai-source income; the remittance rule never applies to them.

3. Assessable income over the threshold. Even with no remittance and no Thai-source income, crossing the filing threshold on assessable income creates an obligation. The commonly cited figures are ฿120,000 for a single filer and ฿220,000 for a married couple on non-employment income, though employment-only income uses a lower threshold in some guidance (closer to ฿60,000/฿120,000). The figure that applies depends on your income category, so confirm with a Thai tax adviser rather than assume the higher number covers you.

One nuance: documented pre-2024 savings (protected under Por 162) and DTA-exempt remittances are generally treated as non-assessable, and non-assessable income doesn't by itself trigger a TIN or return. That's a practitioner interpretation, not a statutory carve-out, and some advisers file a defensive zero return anyway. See remitting pre-2024 savings under Por 162 for the documentation that protects you.

When you need a Tax ID Number (TIN)

A TIN is separate from your passport or visa number, and Thailand doesn't issue one automatically on arrival. You need one once a filing obligation exists under any of the three triggers above: guidance cites a roughly 60-day window from the date you derive Thai-source income, or from the date you remit foreign income once already resident. A mid-year arrival who doesn't remit anything until after passing 180 days may not need a TIN until the year the money actually comes in.

Thailand runs no online TIN application for foreigners as of mid-2026. Register in person (or through an authorized representative) at the Revenue Department district office covering your registered address, with your passport, visa or entry stamp, and proof of address — a lease, TM30 confirmation, or condo ownership document. Processing time varies by office, some issue same-day, and there's no government fee for the TIN itself.

Filing thresholds and deadlines at a glance

Source: ExpatTaxThailand TIN Guide 2026; Wise Income tax for foreigners 2026; PwC Thailand Worldwide Tax Summaries; FRANK Legal & Tax 2026 Tax Return Filing · verified July 2026 · ฿33/USD. Filing threshold exact figure conflicts by income category across sources — treat as directional and confirm with an adviser.

The forms are named by income type: PND.91 for straightforward employment-only income, PND.90 for everyone with other income (rental, freelance, foreign remittances, investments), and PND.94 for certain mid-year non-salary income. The e-filing portal at efiling.rd.go.th has an English guide and most browsers auto-translate the interface, but it's built for Thai filers first — budget extra time your first year, or use a local accountant.

What happens if you don't file

Late filing carries a 1.5% monthly surcharge on unpaid tax, plus a flat penalty guidance describes as up to roughly ฿2,000 per month of delay. Never file at all, and if the Revenue Department later finds you owed tax — via audit, immigration data match, or bank inquiry — the fine can run as high as double the unpaid tax, stacked on the ongoing surcharge. None of this requires deliberate concealment; simple non-filing after crossing a threshold is enough.

The detail that catches out well-meaning expats: you can owe zero tax and still be required to file. If assessable income nets to nothing owed after allowances, deductions, and the first ฿150,000 zero-rated band, but gross assessable income crossed the threshold, the filing requirement still applies. A zero return proves you assessed correctly rather than skipped the process. Unsure whether pensions, remitted savings, or Thai-source rent puts you over the line? The Thailand tax calculator for expats runs the math, and do retirees pay Thai tax on pensions covers pension wrinkles by country.

Frequently Asked Questions

Do I have to file Thai taxes if I don't owe any money?

Yes, if you crossed one of the three triggers — resident and remitted foreign income, Thai-source income, or assessable income over the roughly ฿120,000/฿220,000 threshold — filing is required even if the calculation lands at zero. Skipping the return because "I don't owe anything" is the single most common mistake expats make.

Do I need a Thai bank account to get a Tax ID Number?

No. A TIN is issued on your passport, visa status, and proof of address; it has nothing to do with holding a Thai bank account. DTV visa holders are being refused new Thai bank accounts almost universally in 2026, so budget for that separately — a written answer from a bank branch beats assuming a workaround applies to you.

What's the difference between the 31 March and 8 April deadlines?

31 March 2026 is for a paper return physically received by the Revenue Department. 8 April 2026 is the extended deadline for returns filed electronically through efiling.rd.go.th — but only if the return is actually filed and accepted by that date, not merely started.

Was the remittance tax on foreign income repealed?

No. Por 161/162, taxing foreign-sourced income (earned 2024 or later) when remitted by a tax resident, remains live law in mid-2026. A 2025 draft that would have exempted income remitted within the year earned or the year after was never enacted and lapsed with the February 2026 election. See the remittance tax status page for the latest confirmed position.

Does bringing in savings I had before 2024 require a TIN or return?

Documented pre-2024 savings are generally treated as non-assessable under Por 162, and non-assessable income doesn't typically force a TIN or filing requirement — a practitioner interpretation, not a written statutory exemption. You need a 31 December 2023 closing-balance statement plus proof the funds predate 2024. See remitting pre-2024 savings under Por 162 for the checklist.

The bottom line

Judge your filing obligation by the trigger, not the tax bill. Count your days, know whether you remitted foreign income after becoming a resident, and check your assessable income against the threshold before deciding filing doesn't apply to you. A TIN costs nothing and takes one district-office visit; a missed filing costs a monthly surcharge that keeps compounding until you deal with it. When the numbers are close, get a local accountant to run the actual return rather than guessing from a blog post, this one included.