The Thailand Company Compliance Calendar (2026 Guide).

How Thailand company compliance fits together

Thailand company compliance is a chain, not a list. The monthly books feed the year-end close, the close feeds the audit, the audit feeds the annual general meeting, and the meeting starts two filing clocks at the Department of Business Development while a third clock, the tax return, has been running since the day the books closed.

Miss a link and everything after it slips. That is why the useful way to hold it in your head is as an annual compliance calendar: a fixed sequence of deadlines that repeats every year for as long as the company exists, whether it trades or not.

This guide walks the whole year in order, with every deadline taken from the agency that enforces it. What each engagement looks like when you hand it to a firm lives on the service pages, linked as you go.

The annual compliance calendar at a glance

Here is the full year for a company with a 31 December year end, which is the most common setup. Every deadline is counted from your own closing date, so if your accounting period ends on a different day, shift the annual rows accordingly.

One date on that table is load-bearing: the AGM. Two of the DBD deadlines are counted from it, and it cannot happen until the audit is signed. Companies that get into trouble in April usually lost the race in February, when the audit had not started.

Every month: the books, VAT and withholding

The year-end deadlines are only manageable if the monthly work happens. The Accounting Act makes every Thai limited company responsible for keeping accounting records, in Thai or with a Thai translation attached, and for retaining the records and supporting documents for at least five years after the books close. In practice this means monthly bookkeeping: entering the month's documents, reconciling the bank, and producing the figures the tax filings are built on.

If the company is VAT registered, the Revenue Department's VAT rules set a monthly rhythm on top: the taxable period is the calendar month, and the VAT 30 return with any payment is due within 15 days of the following month. Registration itself becomes mandatory once turnover passes 1.8 million baht a year.

Withholding tax runs monthly too. When the company pays rent, service fees, professional fees and similar items, it withholds tax at source and remits it to the Revenue Department the following month, to fixed deadlines a firm will confirm for your filing profile. The certificates the company issues become the recipients' tax credits, which is why missed withholding surfaces as someone else's problem before it surfaces as yours.

December: close the year

Every company closes its books every 12 months, starting within 12 months of registration. The close turns twelve months of bookkeeping into the annual financial statements: the balance sheet and profit and loss that everything downstream is built on.

The legal frame is Section 11 of the Accounting Act, which requires financial statements to be prepared and submitted within five months of the closing date, and, for limited companies, submitted within one month of being approved at the general meeting. For a company the earlier four-month AGM deadline is what actually drives the timetable, so treat the five-month figure as the outer wall, not the plan.

January to April: the statutory audit

The financial statements cannot go to the shareholders bare. The Accounting Act requires them to be audited and accompanied by the opinion of a certified auditor, and that requirement applies to every limited company whatever its size, including a dormant one. The only exemption is for small Thai registered partnerships under thresholds set by ministerial regulation, which is no help to a company.

The auditor is a licensed professional, not a job title. Under the Accounting Professions Act, the Federation of Accounting Professions issues, suspends and revokes auditor licenses and sets the auditing standards the opinion is signed under. Your bookkeeper cannot audit their own work, so the statutory audit is a separate engagement with an independent auditor, and booking it early in the new year is what keeps the April deadline comfortable. If your company also needs other assurance work, the wider field of audit services in Thailand covers what sits beyond the annual statutory engagement.

By 30 April: the AGM, then two DBD clocks start

The Department of Business Development's filing manual sets out the sequence for a limited company. The audited financial statements must be approved at the annual general meeting within four months of the closing date. The meeting then starts two clocks. A copy of the updated shareholder list (the Bor Or Jor 5 form) is due at the DBD within 14 days of the meeting. The approved financial statements themselves are due within one month of the approval, filed through the DBD e-Filing system.

The same manual is explicit that filing is not optional for quiet companies: every registered juristic person files financial statements annually whether it carried on business or not.

There is a fourth registrar habit worth building alongside these: changes have their own short deadlines all year round. A change of director, for example, must be registered within 14 days of the change. Keeping the share register, the meeting papers and the DBD filings straight is the core of company secretarial work, and it is the part of the calendar most often left to nobody in particular.

By 30 May and 31 August: the tax chain

The Revenue Department runs on its own clock, counted from the closing date rather than from the AGM. Its corporate income tax rules require companies carrying on business in Thailand to file the annual return, Form CIT 50, within 150 days of the closing date, with payment. For a 31 December year end that lands at the end of May, a few weeks after the DBD filing.

The same page sets the half-year obligation: the company estimates its annual net profit and pays half of the estimated tax within two months after the end of the first six months of the accounting period, on Form CIT 51. The prepayment is credited against the annual bill. The estimate deserves care, because a serious underestimate carries its own consequences, and it is the one filing on this calendar that asks for judgment rather than bookkeeping. Corporate tax filing covers both returns and how the year fits around them.

The tax return draws on the same closed, audited books as the DBD filing, which is the practical reason the audit sits where it does in the calendar: finish it once, in time, and both agencies are fed from it.

What happens if you miss a deadline

Each agency enforces its own deadlines, and both sides carry statutory penalties. On the registrar side, late or missing financial statement and shareholder list filings expose the company and its directors to fines. On the tax side, late filing brings fines, and late payment brings surcharges that grow with time. The current amounts depend on the filing and the delay, so have a firm confirm the figures for your situation rather than relying on a table of uncertain vintage.

The indirect costs are usually the ones that bite. A company with missing filings shows up as non-compliant in DBD records, which surfaces during bank reviews, work permit and visa renewals, license applications and any due diligence a buyer or partner runs. Directors also sign these filings personally, so a neglected calendar is not only the company's problem.

Catching up is almost always cheaper than it looks from inside the hole: the filings are the same ones, filed late with penalties, and firms do this routinely.

Running the calendar without living in it

None of these deadlines is difficult on its own. The difficulty is that they arrive every year, on several clocks, from two agencies, and that the annual ones all depend on monthly work being current. Most companies solve this by handing the chain to an accounting firm that runs the books, the filings and the audit handover as one calendar, with the audit itself placed separately for independence.

If you are still at the beginning and the company does not exist yet, it is worth knowing this calendar before you incorporate, because it starts running the day the company is registered. The guide to registering a company in Thailand covers that step; this one is what the years after it look like.

This guide is general information about Thai compliance deadlines, not accounting, tax, or legal advice. Deadlines and requirements are those published by the agencies as of the date above and can change; for a specific company, confirm the current position with a qualified professional.