Who must file
Every company and cooperative files an annual corporate income tax finalisation, even one whose income is exempt. Since 1 January 2026 an enterprise with total annual revenue of VND 1 billion or less pays no corporate income tax at all, but still files. For personal income tax, employers finalise for staff who have authorised them, which an employee may do if they have one employer on a contract of three months or more and are still there at finalisation. An individual files for themselves if they had more than one source of income, unless the extra income averaged VND 15 million a month or less and was taxed at 10% at source, or if they are claiming disaster, illness or other relief. Someone who overpaid and wants neither a refund nor a carry-forward need not file.
Tax year and deadline
The finalisation period is the accounting year for corporate income tax and always the calendar year for personal income tax. Corporate income tax and employer-filed personal income tax finalisations are due on the last day of the third month after the period ends, so 31 March for a calendar-year company. An individual filing their own personal income tax finalisation has until the last day of the fourth month, so 30 April. A company that is dissolving, merging or otherwise ceasing has 45 days from the decision. A foreign resident leaving Vietnam at the end of a contract files before departure, and within 45 days of the contract ending.
Filing step by step
- Pay corporate income tax provisionally each quarter. The four quarters together must reach at least 80% of the final annual liability, or late-payment interest runs from the Q4 deadline on the shortfall.
- File form 03/TNDN with the annual financial statements and whichever appendices apply — loss carry-forward, incentives, foreign tax credit, real-estate transfers, allocation between provinces.
- A micro-enterprise taxed on a percentage of revenue files form 04/TNDN instead and does not have to submit financial statements.
- If you have related-party transactions, attach Appendices I to III on transfer pricing; a Vietnamese ultimate parent with global consolidated revenue of VND 18,000 billion or more also files a country-by-country report within 12 months of its year end.
- Submit on eTax and pay by the deadline. Individuals can check their finalisation data, and query anything that looks wrong, in eTax Mobile.
Penalties for filing or paying late
Under the tax and invoice penalty decree (government full text published 28 August 2026), a taxpayer who files late during an approved filing extension is not penalised, and an individual who files a personal income tax finalisation late but is owed a refund is not penalised for the delay. A taxpayer who files a corrected return and pays the shortfall before the tax office announces an inspection is not penalised for the error. Once the penalty period has expired, the tax is still recoverable for ten years back from the date the breach is found. Late-payment interest is self-assessed and paid with the tax; if it is not computed within 30 days of payment, the tax office calculates it and notifies the taxpayer (Article 16(3), Law 108/2025/QH15).