Thailand taxes company profit at 20 percent, with lower rates for small companies, and every company files twice a year: a half-year prepayment on the PND 51 and the annual return on the PND 50. We prepare the computation, file both, and keep you clear of the underestimation penalty.

Corporate income tax in Thailand is charged on a company’s net profit, not its revenue, at a standard rate of 20 percent. It is a national tax collected by the Revenue Department; there is no separate provincial or municipal corporate tax on top.
A company files twice in each tax year. Halfway through, it prepays tax on its estimated profit through the PND 51. After the year closes, it files the annual PND 50 on its actual profit, credits the prepayment and any tax withheld during the year, and pays or reclaims the difference. The tax year is your company’s twelve-month accounting period, which is set at registration and is not always the calendar year.
A flat 20 percent, with a reduced scale for small companies.
| Net annual profit | Small company rate | Standard rate |
|---|---|---|
| Up to THB 300,000 | 0% (exempt) | 20% |
| THB 300,001 to 3,000,000 | 15% | 20% |
| Over THB 3,000,000 | 20% | 20% |
The reduced scale applies to a company with paid-up capital of THB 5 million or less and annual revenue of THB 30 million or less. Exceed either limit and the flat 20 percent applies to all profit. BOI-promoted companies can hold separate exemptions, and a few sectors such as petroleum are taxed under their own rules.
Thailand splits corporate tax into a mid-year prepayment and a year-end settlement. Both go to the Revenue Department, and the prepayment is credited against the final bill.
| Return | What it is | Based on | Deadline |
|---|---|---|---|
| PND 51 | Mid-year prepayment of corporate income tax | Half of the estimated full-year tax (or actual first-half profit for some companies) | Within 2 months of the end of the first 6 months |
| PND 50 | The annual corporate income tax return | Actual net profit for the full year, less the PND 51 prepayment and tax withheld | Within 150 days of the year-end |
For a company on the calendar year, that puts the PND 51 around the end of August and the PND 50 around the end of May the following year. The annual return is built on the audited financial statements, so the audit has to be done first.
The PND 51 estimate is where companies get caught, too low and you are penalised, too high and your cash is tied up. Let our team set the estimate from your real first-half numbers.
Three groups owe Thai corporate income tax. A company incorporated under Thai law is taxed on its worldwide net profit. A foreign company carrying on business in Thailand, such as through a branch or another permanent establishment, is taxed on the net profit it earns here, and a branch pays a further 10 percent on profit it remits to its head office abroad.
A foreign company with no presence in Thailand but receiving certain income from it, such as dividends, interest, royalties, or service fees, is taxed on that income through a final withholding tax rather than a net-profit return. Which of these applies decides both the rate and the form you file.
The starting point is accounting profit, prepared under Thai Financial Reporting Standards on an accrual basis. That figure is then adjusted for items the Revenue Code treats differently from the accounts, such as non-deductible expenses, depreciation limits, and provisions, to reach taxable net profit. The 20 percent, or the reduced scale, applies to that.
Against the resulting tax you credit the PND 51 prepayment and the tax already withheld on your income during the year on the PND 1, 3, and 53 forms. Losses can be carried forward for up to five years, and records have to be kept for at least five. Because the return runs off the audited statements, clean monthly bookkeeping through the year is what keeps the year-end computation straightforward.
The gap between accounting profit and taxable profit is where the work, and the risk, sits. Have our team prepare the computation and file it off your audited accounts.
Both returns, the computation, and the accounts behind them.
We estimate your full-year profit from real first-half numbers, prepare the PND 51, and file it so the prepayment is right.
The full-year computation, the Revenue Code adjustments, and the PND 50 filed within 150 days, credited with your prepayment and withholding.
We close the books and coordinate the CPA audit the corporate tax return is built on.
The monthly withholding returns, the credits that reduce your bill, and planning before the year closes rather than after.
What company owners in Thailand ask most.
The standard rate is 20 percent of net profit. Small companies pay on a reduced scale: nothing on the first THB 300,000, 15 percent from THB 300,001 to 3 million, and 20 percent above that.
A company with paid-up capital of THB 5 million or less and annual revenue of THB 30 million or less. If it goes over either limit, the flat 20 percent applies to all of its profit.
PND 50 is the annual corporate income tax return. It reports the full year’s net profit and the tax due, and it is filed with the Revenue Department within 150 days of the end of your accounting period, off the audited financial statements.
PND 51 is the half-year return, a prepayment of corporate income tax based on your estimated profit for the full year. It is filed within two months of the end of the first six months of your accounting period, and the payment is credited against the annual bill.
Within 150 days of the end of your accounting period. For a 31 December year-end, that falls around the end of May. Filing online through the Revenue Department’s system can add a few days.
If your actual full-year profit turns out more than 25 percent above the figure you declared, a 20 percent surcharge is added to the shortfall in the half-year tax. A careful estimate from real first-half numbers is what avoids it.
Companies incorporated in Thailand, foreign companies carrying on business here through a branch or permanent establishment, and foreign companies receiving certain Thai-source income such as dividends, interest, and royalties, which is usually taxed by withholding.
Not necessarily. Your tax year is your company’s twelve-month accounting period, set at registration. Many companies use the calendar year, but you can run a different one and change it later with the Revenue Department’s approval.
Yes. A foreign company’s branch pays the 20 percent on its Thai net profit, and a further 10 percent branch remittance tax on the profit it remits to its head office overseas.
Tell us your financial year-end and roughly where your profit sits. Our Bangkok team will handle the half-year PND 51, the annual PND 50, and the computation behind both, filed with the Revenue Department on time.