Personal income tax: PND 90 and PND 91 returns

PND 91 is for taxpayers whose only income is employment income under section 40(1). PND 90 is used when other categories are also present — professional fees, rent, interest, dividends or business income. The paper filing deadline is 31 March of the following year; filing through Revenue Department e-Filing normally attracts an extension of roughly eight extra days. Check the extension notice published for the specific year before you file.

Thailand applies progressive bands to net income, starting with an exempt first slice and rising through several bands to a top rate of 35% on net income above five million baht. Net income is assessable income less the statutory expense deduction for that income category, then less personal allowances. The current band table is published on the Revenue Department website and should be checked each year because it is revised periodically.

A resident taxpayer may claim the same allowances as a Thai national where the conditions are met: the personal allowance, a spouse with no income, children, qualifying parents, health and life insurance premiums with Thai insurers, social security contributions, provident fund contributions, and mortgage interest on a Thai home. Supporting foreign documents such as a marriage certificate or birth certificate must be accompanied by a certified translation when officials request one.

PND 94 is the half-year personal income tax return for taxpayers with income under sections 40(5) to 40(8) — rent, independent professions, contract work and business income. Income received from January to June is reported by the end of September of the same year, and the tax paid is credited against the annual return. Taxpayers with employment income only do not file it.

Yes. e-Filing supports PND 90, 91 and 94 as well as corporate returns. You register once for credentials and complete the system's identity verification. The benefits are the filing extension granted to online filers, automatic computation, and refund status tracking. Taxpayers without a Thai ID card register using the thirteen-digit tax identification number instead.

Tick the refund request on the return you file. The Revenue Department may ask for supporting documents such as the section 50 bis withholding certificates and allowance evidence. Refunds are now paid mainly through PromptPay linked to the tax ID or Thai ID number; taxpayers without PromptPay may instead receive an instrument to collect at a designated bank. Confirm the current refund channel with your area office.

A Thai operator that receives services from a supplier outside Thailand and uses those services in Thailand must remit VAT using form PP 36 within the deadline, and may then claim it as input VAT subject to conditions. Foreign digital platforms supplying end users in Thailand fall under a separate VAT registration regime for foreign electronic service providers.

An employer with one or more employees must register as an employer and register its insured employees with the Social Security Office within thirty days of hiring, and remit contributions by the 15th of the following month. Lawfully employed foreign staff are inside the social security system on the same basis as Thai employees, and the employee's contribution is deductible on the personal income tax return.

Revenue Department Orders P.161/2566 and P.162/2566 provide that a Thai tax resident (present in Thailand 180 days or more in a tax year) who brings foreign-source income into Thailand must include it in that year's personal income tax return, replacing the old practice of exemption when remitted in a later year. P.162/2566 grandfathers income earned before 1 January 2024, which stays outside the new rule. Segregate accounts and keep dated evidence of when income arose, such as statements, share-sale confirmations or contracts.

A company files the half-year return PND.51 within two months after the end of the first six months of its accounting period, and the annual return PND.50 with audited financial statements within 150 days after the year end. Financial statements must be submitted to the Department of Business Development through DBD e-Filing within one month of shareholder approval, and the annual general meeting must be held within four months of the year end.

Foreign employees working legally for a registered employer must be enrolled under Section 33 like Thai staff. The standard contribution is 5% from each side, computed on a wage base capped between THB 1,650 and THB 15,000 per month, so a maximum of THB 750 monthly. Benefits cover sickness, maternity, invalidity, death, child allowance, unemployment and old age; the old-age portion can be claimed on leaving employment and the country under Social Security Office conditions.

Late filing carries a criminal fine of up to THB 2,000 per return plus a surcharge of 1.5% per month on tax due, running from the deadline until payment and capped at the tax amount. Where an assessment officer raises the tax, a penalty of one or two times the additional tax may apply, reducible under Revenue Department regulations. Voluntary amended filings before an audit usually attract a substantially reduced penalty.

Paper returns are due by 31 March of the year following the tax year. E-filing through the Revenue Department system is normally extended by roughly eight additional days under an annual announcement, so check rd.go.th each year — the closing date is not fixed. Filing early also speeds up any refund.

Apply at the responsible Area Revenue Office or the Large Business Tax Administration Division with a copy of the filed PND return and its receipt, passport copies showing entry stamps for the whole tax year, and documents for the income you want treaty relief on. Processing depends on file completeness and office workload — count in weeks, not days. Allow time before the destination country's own deadline.

Yes. The Revenue Code lets spouses choose joint or separate filing per category of income, and the choice affects allowances and the tax base — compare both before deciding. You will additionally need the marriage certificate and both taxpayer numbers. A marriage registered abroad must be translated and legalised first.

Resident taxpayers claim the same allowances as Thai nationals subject to each item's conditions: personal allowance, a non-earning spouse, children, life and health insurance premiums with Thai insurers, qualifying savings funds, and mortgage interest on a Thai home. Products bought from foreign providers are generally not deductible.

At least five years from the filing date, because assessment officers may issue a summons for a retrospective audit within the period allowed by the Revenue Code. Keep filed returns and receipts, 50 Tawi certificates, bank statements, foreign income source documents, and evidence for every allowance claimed.

It certifies Thai tax residence so a foreign tax authority will apply treaty rates instead of full domestic withholding. It is applied for at the Revenue Department with proof of presence, filed returns and income documents, and it is normally paired with an R.O.21 confirming tax actually paid in Thailand. Allow several weeks, so apply before the foreign deadline, not after it.

Highly-skilled professionals working for targeted industries receive a flat personal income tax rate under the relevant royal decree, and some categories are exempt on foreign income subject to conditions. The benefit is tied to the qualifications you filed, so changing employer or role must be reported and can end eligibility. Review your status each year before filing.