Reviewed by ThaiLawOnline, a licensed Thai law firm practising in Thailand since 2006. Thai lawyer of record: Wichuda Atthamethakon, LL.M., Thai Bar Licence 3149/2556.
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Last reviewed: 3 September 2026. Revenue Code sections 41 and 56 were read in Thai on the Revenue Department’s own text of the Code. Section 41 confirms both points this page turns on: the second paragraph taxes foreign income of a person in Thailand when it is brought into Thailand, and the final paragraph fixes residence at one hundred and eighty days in a tax year, not one hundred and eighty-three. Section 56 confirms the March filing deadline and all four thresholds stated below (60,000 and 120,000 baht without a spouse, 120,000 and 220,000 with one, the higher figure in each pair applying where the income is section 40(1) employment income only). The Code’s own cross-references under section 41 paragraph two list Departmental Instructions Por. 161/2566 and Por. 162/2566 and no others, which is the point this page makes about them. Not verified here, and said rather than implied: section 3 Undecim, the sixty-day application deadline, the ten-digit TIN format, the fourteen and ninety day exemption and the office and document practice, all of which come from the Revenue Department’s published guidance rather than from the Code; and the behaviour of individual area revenue offices, which is practice and varies. Re-read on 4 October 2026 for consistency: one answer in the frequently asked questions was aligned with the Revenue Department rule the page states; nothing else changed. Re-checked on 10 October 2026: sections 3 Undecim and 3 Duodecim of the Revenue Code read in Thai (consolidated through amendment No. 54); section 3 Undecim is a power for the Director-General to require a tax number by Gazette notice, not a duty the Code imposes directly, and the page and its FAQ now say so and give the 2,000 baht fine in section 3 Duodecim. The sixty-day deadline, the ten-digit format and the fourteen and ninety day exemption still rest on the Revenue Department’s published guidance; the notice itself was not read. Later the same day: Director-General’s Notifications No. 3 (11 January 2012) and No. 4 (23 July 2012) under section 3 Undecim, and the Revenue Department’s explanation of 16 March 2012, read in Thai on the Department’s site; they make every tax number 13 digits, so the statement that a Revenue Department number is 10 digits was out of date since 2012 and has been corrected. The sixty-day deadline and the fourteen and ninety day exemption were not in those texts and remain as the Department’s guidance states them.
Do You Actually Need a Thai Tax ID?
A Thai Tax Identification Number (TIN) is the number the Revenue Department uses to identify you as a taxpayer. Section 3 Undecim of the Revenue Code empowers the Director-General of the Revenue Department, with the Minister’s approval and by notice published in the Royal Gazette, to require taxpayers and payers of income to obtain and use one; who must apply, and by when, is set by that notice rather than by the Code. Failing to comply with the notice is punishable by a fine of up to 2,000 baht (section 3 Duodecim). Most foreigners who become liable to Thai personal income tax need to apply for it themselves, because they have no Thai personal identification number to use instead.
The Revenue Department states the rule plainly: an individual who has and uses a personal identification number (PIN) under the civilian registration law is not required to apply for a TIN, and may use that PIN when filing. The people who do have to apply are those without a PIN, which in practice means foreigners, along with non-juristic ordinary partnerships, bodies of persons and undivided estates. Source: the Revenue Department’s own Tax Identification page.
⚠️ In practice this is where people get stuck. If you hold a pink ID card or a yellow tabien baan you already have a 13 digit Thai personal identification number, and on the Revenue Department’s stated rule that number is what you file with. Some revenue offices nonetheless open a separate taxpayer record before they will accept a filing. If your office asks you to register, that is an administrative step at that office, not a different legal requirement.
A tax ID is only needed once you are inside the Thai system, which our guide to expat tax in Thailand explains.
This is an example of a Tax ID number in Thailand for a foreigner done in Bangkok on 15th November 2024.
We do not currently register tax IDs for foreigners. We paused that service in early 2025 and have not resumed it. This page is here because the question keeps being asked and most of the answers online are wrong; it is not a sales page. Applying is free and you can do it yourself, and the rest of this page explains how.
Tax Residency: the 180 Day Test
Section 41, final paragraph, of the Revenue Code: “Any person staying in Thailand for a period or periods aggregating 180 days or more in any tax year shall be deemed a resident of Thailand.” The tax year is the calendar year, the days do not have to be consecutive, and the test counts presence, not visa type. A tourist who stays long enough meets it; a work permit holder who leaves early may not.
180, not 183. The 183 day figure belongs to other countries and to some double tax agreement tie breaker clauses, and it is repeated constantly about Thailand. The Revenue Code says 180. Read it yourself in Chapter 3 of the Revenue Code on the Revenue Department site.
Foreign Income Brought Into Thailand
This is the reason most people arrive at this page, so here is the statute rather than a summary of it. Section 41, second paragraph: a resident of Thailand who in the previous tax year derived assessable income from employment or business carried on abroad, or from property situated abroad, “shall, upon bringing such assessable income into Thailand, pay tax in accordance with the provisions of this Part.”
Two things follow that people routinely get wrong. Foreign income is taxed when it is brought in, not when it is earned, so money that stays outside Thailand is outside this provision. And the trigger is residency under the 180 day test above, so a non resident is taxed only on Thai source income.
⚠️ What the Revenue Code does not settle, and where the answer actually comes from. Section 41 sets no time limit between earning and remitting. The timing rule comes from two departmental instructions, which are guidance the Revenue Department issues to its own officers rather than amendments to the Code: Revenue Departmental Instruction Por. 161/2566, issued 15 September 2023, and Por. 162/2566, issued 20 November 2023, which added a paragraph to the first. Both were read in the original Thai on the Revenue Department’s own site: Por. 161/2566 as amended (PDF, rd.go.th), which carries the amending paragraph from Por. 162/2566 in its text.
Read together they set a two part test, and the Revenue Department states it that way in its own published question and answer on the two instructions. Foreign source income is taxable if (1) the income arises on or after 1 January 2024, in a tax year in which you are in Thailand for 180 days or more, and (2) you bring that income into Thailand in that same year or in any later year. Where both are met, it is taxed in the year you bring it in. Por. 162/2566 is the provision that puts income arising before 1 January 2024 outside the rule, and Por. 161/2566 applies to income brought into Thailand from 1 January 2024 onwards.
No later departmental instruction amends either of them. The Revenue Department’s own index of instructions runs into 2026 and lists only these two under section 41 paragraph two. That is a statement about departmental instructions only, so if your position turns on a large sum or an unusual year, confirm it with the Revenue Department or a Thai tax adviser.
The Two Deadlines
These are different dates and confusing them is the most common mistake on this subject.
- Applying for the TIN: within 60 days from the date you derive assessable income. That is the Revenue Department’s stated rule for a person liable to personal income tax who has no PIN, on its Tax Identification page. It runs from the income, not from your arrival and not from the filing season.
- Filing the return: on or before the last day of March each year, for the income of the preceding calendar year. That is Section 56 of the Revenue Code, and it is a standing rule rather than a one off date. Section 56 also sets the thresholds at which filing becomes compulsory: assessable income above 60,000 baht if you have no spouse, or above 120,000 baht if that income is employment income only, and 120,000 and 220,000 baht respectively if you have a spouse.
Some foreigners are outside the system entirely. The Revenue Department states that a foreigner present in Thailand for one period not exceeding 14 days, and not exceeding 90 days in aggregate within a tax year, does not need to apply for a TIN.
How to Apply, Step by Step
Applying is free. The forms are in Thai, which is the only genuinely hard part, and a Thai speaking friend or a power of attorney solves it.
- Check that you actually need one. If you hold a Thai personal identification number and your office will accept it, you may not. If you have no PIN and you have Thai assessable income, you do.
- Fill in Form L.P. 10.1, the application for individuals. Non juristic ordinary partnerships and bodies of persons use L.P. 10.2, and juristic persons use L.P. 10.3.
- Go to an area revenue office. Useful detail that is rarely mentioned: the Revenue Department states that an individual may file the application at any area revenue office or branch, regardless of where he is domiciled. Companies do not get that latitude and must use the office for their head office location.
- Bring proof of who you are and where you live. Passport and visa, plus address evidence. Offices ask for different things and often ask for a lot: a lease, or the blue tabien baan of the owner of the property you live in. If you live in a Thai spouse’s property, bring the marriage certificate with copies of their Thai ID card and tabien baan.
- Keep the number. You will need it for every future filing, and you should tell the office if your details change.
What a Thai TIN Looks Like
People search for the format constantly, so: every Thai tax identification number is now 13 digits. Since 1 February 2012 an individual files with the 13 digit personal identification number on their Thai ID card, pink ID card or yellow tabien baan, a company uses its 13 digit registration number from the Department of Business Development, and anyone with neither, which in practice means most foreigners, is issued a 13 digit number by the Revenue Department (Director-General’s Notification No. 3 of 11 January 2012, and the Department’s explanation of 16 March 2012). The older 10 digit Revenue Department numbers could be used only until 31 January 2013, which is why the 10 digit figure still appears in older guidance, including some of the Department’s own English pages.
Additional Resources on How to Register a Tax ID Number in Thailand
For more information, please visit our website or contact us directly. Write to us at info@thailawonline.com. We are here to assist you in navigating the new tax regulations and ensuring you are fully compliant with Thai law.
Additional links about how to register a Tax ID number in Thailand:
- Tax Identification, the Revenue Department’s own page. Who must apply, the 60 day deadline and the L.P. 10 forms come from here; its 10 digit format is out of date (see above).
- Revenue Code, Chapter 3, Income Tax (Sections 38 to 64), in English on the Revenue Department site. Section 41 is the residency and remittance rule, Section 56 the filing duty.
- Personal Income Tax overview, the Revenue Department’s summary of how the tax works.
- Our 2024 explanation of the foreign income rules (PDF). Written in 2024, so check the current position before relying on it.
Frequently Asked Questions
Who needs a tax ID number in Thailand?
Under Section 3 Undecim of the Revenue Code, the Director-General requires taxpayers to obtain and use a TIN. The Revenue Department exempts individuals who already hold a Thai personal identification number, who may use that instead, so in practice it is foreigners without a PIN who must apply. A foreigner in Thailand for one period of no more than 14 days, and no more than 90 days in total in a tax year, does not need to apply.
How do I get a tax ID number in Thailand?
File Form L.P. 10.1 at an area revenue office with your passport, visa and proof of address, within 60 days of deriving assessable income. It is free. An individual may file at any area revenue office regardless of where they live. Employees often have this arranged by their employer.
Is a tax ID the same as a work permit?
No. A tax ID is issued by the Revenue Department for tax purposes and is separate from the work permit issued by the Department of Employment.
Do retirees need a Thai tax ID?
The residency test is 180 days or more in a tax year, not 183 (Revenue Code Section 41). If you meet it and you have assessable income, including foreign income you bring into Thailand, you may need a TIN. If you already hold a Thai personal identification number, the Revenue Department’s rule is that you may file with that instead.
Can a foreigner get a tax ID without a work permit?
Yes. The Revenue Department’s rule turns on whether you derive assessable income, not on whether you hold a work permit, so a foreigner with Thai rental income, or a resident bringing foreign income into Thailand, applies in the same way. Area revenue offices differ in the documents they ask for.
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