Year-End Accounting
& Tax Filing

PND.50, the annual corporate income tax return, must be filed within 150 days after the end of your company's fiscal year. For most Thai companies with a December 31 fiscal year-end, this means the PND.50 deadline falls on May 31 of the following year. Late filing incurs a surcharge of 1.5 percent of the tax due per month of delay, plus a fixed penalty that may range from one to two times the tax owed. In addition to PND.50, companies must also file PND.51, the mid-year tax estimate, within 60 days of the sixth month of the fiscal year. Both deadlines are tracked and managed by our team from the start of your fiscal year.

Yes. All registered Thai limited companies are legally required to have their annual financial statements audited and certified by a licensed CPA or TA before submission to the Department of Business Development. This requirement applies regardless of revenue size — even dormant companies or those that recorded no business activity during the year must still complete a statutory audit. The certified financial statements must be presented and approved at a shareholders' meeting before submission. PTNP Accounting has licensed CPA and TA auditors on our team who perform this certification as part of our year-end service.

Both CPA and TA auditors are licensed to certify financial statements for Thai companies, but they are issued by different regulatory bodies. A CPA holds a license issued by the Federation of Accounting Professions (FAP) and is authorized to audit and certify all types of financial statements submitted to the Department of Business Development. A TA holds a license issued directly by the Revenue Department and is specifically authorized to certify tax-related financial statements, including those submitted with PND.50 and PND.51. PTNP Accounting holds both CPA and TA licenses, which means we can certify your full financial statements and your corporate tax returns without needing to involve a separate auditing firm.

Yes, we can take over year-end filing even if another firm or you yourself handled the monthly bookkeeping. Before we begin, we will review your existing bookkeeping records — the general ledger, trial balance, bank reconciliations, and supporting documents — to assess their accuracy and completeness. If your records are well-organized, we can proceed to financial statement preparation with minimal additional work. If there are gaps, errors, or incomplete entries, we will need to reconstruct or correct those records first. We will be transparent about what is needed and the expected cost before we proceed.

Failing to submit certified financial statements to the Department of Business Development on time exposes company directors to significant legal and financial penalties. The DBD can issue fines ranging from THB 50,000 to THB 200,000 against directors personally for each year of late submission. In addition to monetary fines, the company may be flagged in the DBD system for non-compliance, which can cause complications when renewing business licenses, opening bank accounts, or applying for BOI promotion. The DBD submission deadline is five months after your fiscal year-end.