For most Thai companies the fiscal year ends on 31 December, starting a sequence of audit, AGM and filing deadlines. This article explains what to prepare and when.

A practical guide to the Thai Tax Residency Certificate (Form R.O. 22): what it confirms, who qualifies under the 180-day rule, how to apply, and the key difference between residency and tax payment certificates.

A practical guide to PND 51, Thailand's half-year corporate income tax return: who must file, how to calculate the estimate, the 2026 deadlines, and how to avoid the 20% underestimation surcharge.

A practical guide to PND 90 and PND 91 in Thailand: who needs to file, which form to use, key deductions and allowances for 2025, and what changed for foreign income since January 2024.