Will there be penalties for submitting supplementary related-party transaction appendices? This is a question frequently asked by many FDI businesses, multinational corporations, and entities with related-party transactions. In reality, the penalty level depends not only on whether the business made incorrect or incomplete declarations, but also on the timing of the supplementary submission, the extent of the impact on tax obligations, and the tax authority's inspection status. By proactively reviewing and submitting supplementary related-party transaction appendices on time, businesses can avoid penalties under Article 20% for incorrect declarations and significantly reduce the risk of tax assessment. This article will help businesses understand each penalty scenario, the standard implementation process, and important considerations for optimizing tax risk management.
The role of the Related Party Transaction Appendix in tax filings.
According to the provisions of Decree 132/2020/ND-CP and additional guidance documents at Decree 20/2025/ND-CP (Applicable to tax periods from 2025 onwards), the Related Party Transaction Appendix is a mandatory and inseparable component of the Corporate Income Tax (CIT) Final Settlement dossier.
When a business discovers discrepancies in the information on this form, submitting a supplementary appendix to the related-party transaction report is not only a legal responsibility but also a way to ensure transparency in the data. For a better understanding of the required fields, businesses can refer to the detailed instructions. related party transaction appendix For comparison with your current records. This appendix serves as the basis for the tax authorities to determine:
- The limit on interest expense (EBITDA) is valid according to the 30% ceiling.
- Honesty in determining transaction prices according to the Arm's Length Principle.
- The risk of eroding government revenue through the transfer of profits abroad.
If a business is late in submitting the supplementary appendix to the related-party transaction records, the tax authority's risk management system will automatically rank the business as a high-priority audit target, impacting its long-term business operations.
So, will submitting an addendum to the related-party transaction records result in a penalty?
Based on the Law on Tax Administration No. 38/2019/QH14 and Decree 125/2020/ND-CP, the level of penalties for enterprises voluntarily submitting supplementary appendices on related-party transactions is classified based on the impact on the amount of tax payable:
Making supplementary payments does not change the tax liability.
This is a case where a business adjusts its identification information or corrects mechanical data errors, but the total corporate income tax remains unchanged.
- Penalty: A fine of VND 1,500,000 to VND 2,500,000 may be imposed for providing incorrect information on tax returns.
- Note: However, proactively submitting supplementary related-party transaction appendices before an audit decision is made is often considered an important mitigating circumstance.
Making supplementary payments results in additional tax payable.
This is a common situation when businesses review interest expense and discover that the amount exceeding the limit has not been properly excluded.
- Benefits: If a business submits the supplementary appendix on related-party transactions before the tax authority announces the inspection decision at its headquarters, the business will not be penalized under Article 20% for incorrect declaration.
- Obligation: Businesses only need to pay the outstanding tax amount and late payment penalty (0.031 TP3T/day). This is why MAN – Master Accountant Network always recommends that businesses submit supplementary related-party transaction appendices as soon as errors are discovered to reduce the burden of penalty costs.
Submit additional documents after the inspection or audit decision is made.
At the time of the inspection decision, the submission of supplementary related-party transaction appendices will no longer be considered voluntary. Businesses will be subject to back taxes, penalties for incorrect declarations (Circular 20%), and may have their tax assessed if the documentation is deemed unreliable.
Material errors that necessitate the submission of supplementary appendices to related-party transactions.
Why do many businesses have to submit supplementary related-party transaction appendices multiple times? Below are some common errors that MAN has compiled from its audits:
- Incorrect identification of related parties: The most common mistake is omitting related-party relationships when a business borrows capital from individual executives or banks with loan-to-value ratios exceeding the limits stipulated in Decree 132. Upon discovering this, the business is required to submit an appendix detailing related-party transactions to adjust the entire transaction statement.
- Errors in EBITDA calculation: Accountants often forget to add back interest expense and depreciation when calculating EBITDA according to tax law (which differs from accounting EBITDA). This error directly leads to incorrect corporate income tax determination and requires immediate submission of related-party transaction appendices.
- Lack of information on pricing methodology: Failure to specify the profit-comparison method or the cost-plus method renders the documentation incomplete, leading to the need to submit an appendix on related-party transactions to supplement the information required by management.
- Data discrepancies between years: Inconsistencies in carrying forward uncredited interest expenses from one year to the next are also a reason why businesses have to submit supplementary related-party transaction appendices for multiple tax periods simultaneously.
Other related penalties to note
Besides the issue of submitting supplementary appendices to related-party transactions, businesses need to understand the administrative penalty fee schedule for other violations to gain an overall view of the risks:
| Violation | Penalties as stipulated in Decree 125/2020/ND-CP |
| Failure to submit the appendix with the tax return. | 8,000,000 – 15,000,000 VND |
| Late filing of tax returns (including related-party transaction appendices) | Up to 25,000,000 or more depending on the length of the delay. |
| No documentation was created to determine transfer pricing. | 8,000,000 – 15,000,000 VND |
| Incorrect declarations lead to tax evasion. | 20% Amount of underdeclared tax |
Clearly, the cost of voluntarily submitting supplementary related-party transaction appendices is much lower than the cost of facing tax authorities collecting back taxes and imposing penalties after an audit.
The impact of Decree 20/2025/ND-CP on declaration procedures.
The regulations of Decree 20/2025/ND-CP are now coming into effect. These changes may require businesses to review their documentation and submit supplementary appendices on related-party transactions to comply with the new standards.
- Expanding the definition of "Essential Control": Even without sufficient equity stake, if a business has the power to make decisions regarding senior personnel or financial strategy in another business, it is still considered an affiliated party. Many entities have had to submit supplementary related-party transaction appendices because they previously relied solely on the percentage of share ownership.
- Automatic Exchange of Information (AEOI) Mechanism: Vietnamese tax authorities can now compare data from subsidiaries in Vietnam with the parent company's country-by-country profit reports. Discrepancies in revenue or profit margins will result in a request for the company to submit supplementary related-party transaction appendices for explanation.
- Interest expense deduction: New regulations on offsetting interest on loans and interest on borrowed capital when calculating EBITDA benefit businesses. Therefore, some businesses are submitting supplementary appendices on related-party transactions to claim tax refunds or reduce their tax liability for the previous year.
A real-world case study of proactively submitting supplementary appendices to related-party transactions.
To understand why proactively reviewing records is vital to a business's cash flow, let's analyze the following scenario:
Context: An FDI enterprise borrowed VND 100 billion from bank X, with equity capital of VND 150 billion. Because the loan-to-equity ratio exceeds 25% of the equity capital and bank X has the right to intervene in key financial decisions, this is identified as an affiliated relationship. In 2023, due to an oversight, the accountant did not declare this relationship and did not exclude the portion of interest expense exceeding 30% of EBITDA.
In early 2025, after a review, the company discovered it had underdeclared corporate income tax by 1.2 billion VND.
Option 1: Proactively submit supplementary appendices to related-party transactions.
Businesses can voluntarily submit supplementary documents in May 2025. At that time:
- Tax arrears: 1.2 billion VND.
- Late payment penalty for 2 years: 1.2 billion x 0.03% x 730 days = 262,800,000 VND.
- Administrative penalty: 0 VND (Due to voluntary payment of additional fees before the inspection decision was issued).
- Total cost: 1.462 billion VND.
Option 2: Only proceed with the supplementary work after the inspection decision is made.
When an inspection is scheduled for October 2025 and this error is discovered, then:
- Tax arrears: 1.2 billion VND.
- Late payment penalty for 880 days: 1.2 billion x 0.03% x 880 days = 316,800,000 VND.
- Penalty for incorrect declaration (20% on the amount of tax underpaid): 1.2 billion x 20% = 240 million VND.
- Total cost: 1.756 billion VND.
Comparison results: By proactively submitting supplementary related-party transaction appendices, the company saved 294 million VND. More importantly, the company maintained its tax compliance record, reducing the risk of being subjected to rigorous audits in subsequent years. The lesson learned is that submitting supplementary related-party transaction appendices is a safe and effective financial protection solution for businesses with related-party transactions.
Standard procedure for submitting supplementary appendices to related-party transactions.
To ensure accuracy, accountants need to follow the procedure for submitting supplementary appendices to related-party transactions, specifically as follows:
Step 1: Data reconciliation and preparation
Use data from the Local File and Master File as a basis. Re-check the indicators on Form 01 against the original records to accurately determine the figures that need adjustment.
Step 2: Perform operations on the HTKK software.
After identifying the necessary adjustments, the business proceeds with the technical procedures on the declaration system according to the instructions below:
- Select "Submit supplementary declaration" for the corporate income tax return.
- Update the latest figures in the related party transaction appendix.
- Note: When submitting supplementary related-party transaction appendices, the system will require you to attach an explanation of any errors.
Step 3: Complete the KHBS explanation form (Form 01-1/KHBS according to Circular 80/2021/TT-BTC)
Clearly describe whether the error was due to a misunderstanding of regulations regarding related parties or an error in EBITDA calculation. A detailed explanation will expedite the process of submitting the related-party transaction appendix to the tax authorities.
Step 4: Submit your application and fulfill your financial obligations.
Submit your tax return online and pay the applicable tax immediately. Keep proof of submission of the related-party transaction appendix for future reference.
Expert advice on affiliate marketing to optimize tax management.
Submitting supplementary appendices to related-party transactions should be considered part of a routine internal control process. Businesses should not wait until the last minute before an audit to conduct a review.
- Conduct quarterly tax reviews: Examine intra-company transactions to ensure they remain within market price ranges. This helps minimize the need to submit supplementary related-party transaction appendices.
- Technology update: Utilize accounting software that integrates related-party transaction alerts and automatic EBITDA calculation to minimize human error.
- Expert consultation: For complex transactions such as franchising or corporate fee management, consultation is recommended. related party transaction advisory services Obtain information from specialized, reputable, and experienced units before filing your tax return to avoid having to submit supplementary related-party transaction appendices multiple times.
Conclude
In summary, submitting the supplementary related-party transaction appendix in 2026 is a positive step that helps businesses minimize the risk of heavy penalties and improve legal compliance. Although a late payment penalty may be incurred, it ensures legal security and enhances the company's reputation with the Tax authorities.
Instead of waiting for tax authorities to conduct an audit before taking action, businesses should establish a process for regularly reviewing related-party transaction records, especially those related to EBITDA, interest expense, identification of related parties, and transfer pricing documentation. This forms the foundation for ensuring sustainable compliance and optimizing financial management efficiency in the long term.
If a business is unsure whether its current documentation is complete or needs to submit supplementary related-party transaction appendices, consulting with experts early on will always be far more cost-effective than post-audit processing. A proactive decision can help businesses avoid significant risks in the future.
Contact MAN – Master Accountant Network For expert support and free consultation!
Contact information MAN – Master Accountant Network
- Address: No. 19A, Street 43, Tan Thuan Ward, Ho Chi Minh City
- Mobile/Zalo: 0903 963 163 – 0903 428 622
- Email: man@man.net.vn
Content production by: Mr. Le Hoang Tuyen – Founder and CEO of MAN – Master Accountant Network, CPA Vietnam with over 30 years of experience in accounting, auditing, and financial consulting.