Explanation on the procedure for corrected tax returns for unreported input VAT
2026/01/15
- Quang Thi Hoai Nhu
Introduction
Omission of input VAT invoice declaration is a common issue during corporate tax filing and affects the amounts declared in corporate tax returns. This report explains the declaration methods and additional deductions in case an omission of input VAT declaration is discovered.
We hope this report will assist in avoiding tax risks.
1. Principles of declaration and deduction of input VAT, and amended declarations in cases of omission.
Principles of Declaration and Deduction of Purchase VAT
In principle, VAT related to purchases incurred during the current period should be declared and deducted in the period in which the purchases occurred, regardless of whether the goods have been used or remain in inventory.
In the past, based on Official Circular 156/2013/TT-BTC (which expired on January 1, 2022) and the guidance in Official Letter No. 4943/TCT-KK from the General Department of Taxation, additional declarations and deductions were allowed in the period when undeclared taxes were discovered, but they had to be made before the issuance of the tax audit decision notification by the tax authorities.
However, under the current regulations based on Government Decree No. 126/2020/ND-CP (effective December 5, 2020), if it is found that there are errors in the tax returns already submitted to the tax authorities due to omission of VAT invoices, taxpayers are required to correct the previously erroneous returns.
In other words, the omitted VAT invoices must be corrected not at the time they are discovered, but by filing amended returns in each period in which the purchase VAT invoices were originally generated.
Amended tax returns filed before the issuance of a notice of tax audit or tax inspection determination
The following varies according to changes in tax obligations at the time of amended declaration.
・If an additional payment arises due to a revised tax return, or if an excessive refund occurs due to a decrease in the refund amount, in addition to the additional payment amount or the refunded excess tax amount, interest on overdue payments must be paid.
・If no additional payment arises due to the revised tax return, and only the amount of deductible input VAT carried forward to the next period increases or decreases, it is necessary to file the return by entering the respective increase or decrease amounts under the “increase adjustment” and “decrease adjustment” items on the current period’s tax return.
If the purchase VAT amount planned for refund application is expected to increase in the future, a corrected tax return must be filed before submitting the next tax return or refund application.
Amended tax returns filed after the issuance of a decision notice for tax audits or tax inspections
Although it is possible to file an amended tax return even after the tax authorities and jurisdictional bodies have issued a notification of decision for a tax audit or inspection, it is important to note that if additional payments or excessive refunds occur due to undeclared income, additional administrative fines may be imposed as violations in tax management.
Amended tax returns after tax audits and tax examinations
If previously undeclared income is discovered after the tax authorities or competent agencies have notified the results of a tax audit or inspection and the processing decision, a corrected tax return must be filed as follows.
It is important to note that when the amount of tax payable decreases, there are differences compared to the situation before the mentioned audit took place.
・In cases where additional payments occur or the deductible or refundable amount decreases: amended tax returns are permitted, but administrative penalties will be imposed for additional payments or excessive refunds.
・In cases where the payable tax amount decreases or the amount eligible for deduction or refund claims increases: amended tax returns are not allowed, and the procedures must be carried out according to the provisions for filing tax objections.
2. Causes and Improvement Methods for Undeclared VAT Invoices
If invoice information is not sufficiently shared among departments within the company, there is a high likelihood of omission in filings. Also, in companies with a high volume of transactions, a shortage of personnel can cause delays in the invoice verification process. Furthermore, there are cases where invoice issuance by suppliers is delayed; in such situations, it is important to be aware that the risk of omissions in filing increases.
To prevent declaration omissions, it is important to verify VAT invoices and reconcile them with accounting records.
In addition, improvements can be achieved by establishing systems to reduce the risk of declaration omissions through measures such as introducing specialized software and systems, sharing VAT invoices among internal departments, and regularly reconciling accounts payable and receivable with suppliers.
Conclusion
Companies need to properly manage VAT invoices and file them at the appropriate times to avoid tax-related risks, and if unfiled returns are discovered, they must promptly file amended returns for the relevant period.
If amended returns are not filed in the appropriate period, it can become an issue during future tax audits, increasing administrative burdens such as explanations to tax authorities and posing risks that may affect future input VAT refund processes.
This article was translated using Yarakuzen.
Reference
- Tax Management Law No. 38/2019/QH14 dated June 13, 2019
- Government Decree No. 126/2020/ND-CP dated October 19, 2020
- Notification No. 219/2013/TT-BTC dated December 31, 2013
- Notification No. 219/2013/TT-BTC dated December 31, 2013
- Official Letter No. 2397/CTBNI-KKKTT dated June 27, 2023
- Official Letter No. 4943/TCT-KK dated November 23, 2015
