When is the Thai tax return deadline for expats?

Thailand taxes by calendar year, so the return you file in the spring covers 1 January to 31 December of the year before. Filing online gives you eight more days, and nothing else changes.

The dates

Which form is yours

PND 91 is the salary-only return. PND 90 covers income beyond employment, or a mix of sources, which is what most self-employed remote workers and freelancers file. Only some taxpayers owe the half-year PND 94, so ask the Revenue Office whether your income category is covered before assuming you owe a September return.

Whether you have to file at all

Filing is triggered by assessable income, not by residency on its own. For PND 90 the threshold is assessable income above 60,000 THB for a single filer or 120,000 THB if married. For PND 91 it is 120,000 THB single and 220,000 THB married. A resident is assessable on Thai-source income and on foreign income brought into Thailand, and foreign income earned before 1 January 2024 sits outside the current remittance rule, so a resident who remitted nothing new may have nothing to file.

If you miss the date

Filing late brings a fine of up to 2,000 THB. Tax paid late carries a surcharge of 1.5 percent per month on the unpaid amount. The Revenue Department lets you split personal income tax above 3,000 THB into up to three instalments without fines or surcharges, which is the first thing we would ask about if the cash is the problem.

Filing needs a Thai tax identification number, which the Revenue Department issues free when you apply in person with form L.P.10.1 at the district office for your address, bringing your passport, your entry stamp and proof of address that matches your TM30 record. The Thai tax guide covers the sequence end to end.