Tax audit services are a key solution that helps Vietnamese and FDI businesses proactively review their accounting systems and documents before authorities conduct inspections. In this context... Law on Tax Administration No. 38/2019/QH14 With the latest guiding circulars tightening regulations on related-party transactions and electronic invoices, conducting audits has become more urgent than ever.
According to statistics from the General Department of Taxation, more than 701 businesses were subject to back taxes and administrative penalties during tax settlements due to objective errors in the application of policies. Therefore, using tax audit services is not only a way to verify the accuracy of data but also a strategic consulting tool, helping businesses maximize the benefits of current tax incentives.
What is tax audit service? Concept and legal nature
Tax auditing services are understood as the independent examination and evaluation activities of certified auditors to verify the accuracy and reasonableness of tax reports and the compliance of businesses with legal regulations. Unlike regular financial statement audits, tax audits focus in depth on core taxes such as Corporate Income Tax (CIT), Value Added Tax (VAT), Personal Income Tax (PIT), and Contractor Tax.
Based on the Independent Auditing Act 2011, this service provides an objective view of the financial health of a company from a tax perspective. The results of this process not only serve the company's management but also provide a reliable basis for working with government agencies, banks, and strategic partners.
Distinguishing between tax audit and tax inspection
To better understand tax audit services, businesses need to clearly distinguish them from inspection and examination activities by tax authorities to avoid legal misunderstandings:
| Criteria | Tax audit (Independent service) | Tax inspectors (Government agency) |
| The implementing entity | Independent auditing firm (such as MAN) | Inspection team from the General Department of Taxation/Tax Office |
| Nature | Voluntary (or mandatory depending on the target group) | Mandatory according to plan or indication of violation |
| Purpose | Identify errors for correction and advise on cost optimization. | Checking compliance and handling violations of the law. |
| Final result | Audit report, management advisory letter | Inspection report, penalty decision, and recovery of funds. |
| Utility value | Internal risk management, enhancing credibility with partners. | Legal basis for paying additional taxes and penalties. |
Legal basis governing tax audit activities
In 2025, auditing and tax filing activities will be governed by the following important legal documents:
- Law on Tax Administration No. 38/2019/QH14: Provides a framework outlining the obligations of taxpayers.
- Decree 123/2020/ND-CP: Regulations on electronic invoices and documents – the focus of current tax audits.
- Circular 80/2021/TT-BTC: Guiding the implementation of some provisions of the Law on Tax Administration.
- Decree 132/2020/ND-CP: Regulations on tax management for enterprises with related-party transactions.
Misapplying any provision in these circulars can lead to enormous financial risks, which is why professional tax audit services become a "shield" protecting businesses.
Why should businesses use tax audit services today?
The constant fluctuations in economic policies and periodic inspections by authorities keep businesses constantly worried about tax risks. Hiring tax audit services offers superior value that in-house accounting teams sometimes cannot fully provide due to overlapping work responsibilities.
Detecting and preventing risks of administrative violations.
Most tax errors are not intentional but rather due to accountants failing to keep up with new legal regulations. Tax audit services help review all input and output invoices, checking the validity of expenses without invoices or exceeding limits. Early detection allows businesses to proactively file supplementary tax returns, minimizing late payment penalties (currently 0.031 TP3T/day on the amount of tax overdue).
Optimizing the amount of tax payable legally.
Many businesses miss out on tax incentives due to a lack of understanding of the applicable conditions. Auditors can help businesses identify deductible expenses for corporate income tax purposes, tax exemptions in high-tech and education sectors, or incentives based on investment location. This is the direct economic value that tax audit services provide.
Enhancing financial credibility and transparency.
For companies preparing to raise capital (Series A, B, etc.) or conduct an IPO, a tax audit report is the strongest evidence of transparency. Investors will have more confidence in profit figures knowing that tax obligations have been verified by a third party as posing no potential risks.
Standard tax audit service procedures at MAN
At MAN – Master Accountant Network, we apply a rigorous auditing process to ensure that no errors, however small, are overlooked. Services tax audit Our process includes the following steps:
Step 1: Conduct a site survey and develop an audit plan.
We conduct research into the specific characteristics of each industry (manufacturing, services, import/export, etc.) to identify key tax categories. Based on this, our team of experts will develop a detailed plan outlining the timeline and personnel required for implementation.
Step 2: Review the internal tax control system.
Assess how the business stores invoices, approves payments, and prepares monthly/quarterly tax reports. If the control system is lax, the risk of errors will be very high.
Step 3: Review the tax details (Fieldwork)
This is the core phase of tax audit services:
- For VAT: Verify the legality of the invoice, compare the balances of accounts 133 and 3331 with the tax return.
- Regarding Corporate Income Tax: Review the non-deductible expenses according to Article 6 of Circular 78/2014/TT-BTC (amended).
- Regarding Personal Income Tax: Review documents related to family allowance deductions, employment contracts, and calculate progressive tax rates.
Step 4: Discuss the identified issues and make recommendations.
After the review, we will hold a meeting with the management and chief accountant to explain the errors. At this point, the tax audit service acts as a consultant, guiding the business on how to adjust its accounting records and submit supplementary tax returns in accordance with regulations.
Step 5: Issue the audit report and management letter.
The final report will summarize the company's overall tax compliance status, along with warnings about future risks.
Detailed content of tax audit services for major tax types.
To give businesses a clearer picture, here is a list of the most important tasks that tax audit services perform for each type of tax.
Value Added Tax (VAT) Audit
Value Added Tax (VAT) is the tax most prone to invoice errors. In 2025, with the implementation of electronic invoices (100%), checking the synchronization between data on the General Department of Taxation's portal and accounting records will be mandatory.
| Content of the test | Audit objectives |
| Input invoices | Verify the validity of invoices from businesses that have absconded or ceased operations. |
| Deduction conditions | Verify non-cash payment documents for invoices exceeding 20 million VND. |
| Tax return | Compare the figures between the monthly tax return and the ledger accounts 133 and 3331. |
| VAT refund | Review tax refund records for investment projects or export goods. |
Corporate Income Tax Audit
This is the most complex part of tax auditing services. Auditors must have in-depth knowledge to distinguish between "accounting expenses" and "tax-deductible expenses".
Key review areas:
- Depreciation costs of fixed assets (according to Circular 45/2013/TT-BTC).
- Salary and wage costs (employment contracts, financial regulations).
- Interest expense (especially the interest rate ceiling under Decree 30% for enterprises with related-party transactions as per Decree 132).
- Provisions for inventory devaluation and bad debts.
Personal Income Tax Audit
Tax audit services help businesses review their employee lists, tax-exempt allowances, and tax settlements for expats. Incorrect calculation of resident and non-resident status often results in significant back taxes.
Which entities are required to use tax audit services, and which should?
Not all businesses are legally required to undergo audits, but proactively utilizing tax audit services is a smart management strategy.
The group of entities required to have their financial statements (including tax statements) audited.
According to Decree 17/2012/ND-CP, the following entities must undergo annual audits:
- Foreign direct investment (FDI) enterprises.
- Credit institutions, branches of foreign banks.
- A public company, listed on the stock exchange.
- State-owned enterprises.
Businesses should proactively opt for voluntary tax audits.
- Businesses prepare for tax settlement (usually every 3-5 years).
- Businesses are expanding rapidly, and their accounting systems haven't kept pace.
- Businesses with numerous related-party transactions face a high risk of transfer pricing.
- The entities are preparing to carry out mergers and acquisitions (M&A).
Important notes regarding penalties for tax violations.
To fully appreciate the value of tax audit services, businesses need to understand the severity of current penalties under Decree 125/2020/ND-CP:
- False declarations resulting in underpayment of taxes: Penalty under Article 20% for the amount of tax underpaid or the amount of tax refunded in excess.
- Tax evasion: Penalties range from 1 to 3 times the amount of tax evaded.
- Violations of tax filing deadlines: Fines can be up to 25 million VND depending on the length of the delay.
- Late payment penalty: calculated at 0.031 TP3T/day on the amount of tax overdue.
Tax audit services help eliminate these penalties by adjusting the figures correctly before the tax authorities announce a decision to conduct an on-site inspection.
Common errors that tax audit services often detect.
Based on MAN's practical experience, here are the most common mistakes businesses often make:
- Illegal invoices: Using invoices from "shell companies" created solely for the purpose of selling invoices. The General Department of Taxation's current system can easily track these cases.
- Non-business expenses: Personal expenses of the business owner that are included in company expenses.
- Forgetting to notify the tax authorities about invoice issuance: Even after switching to electronic invoices, errors in the digital signing process and data submission to the tax authorities can still occur.
- Incomplete related-party transaction records: This is a critical error for FDI businesses, leading to tax assessments.
When using tax audit services, these errors will be identified and optimal solutions will be proposed, helping businesses avoid unnecessary legal troubles.
Price list for tax audit services (for reference)
The cost of tax audit services is not a fixed figure but depends on the scale of revenue, the number of documents, and the complexity of the industry.
| Annual revenue (VND) | Scope of work | Estimated fee (Million VND) |
| Under 20 billion | Review of the fiscal year | 15 – 25 |
| 20 billion - 100 billion | In-depth tax review | 30 – 60 |
| Over 100 billion | Comprehensive Audit & Related Party Transactions | Contact us for a survey. |
| FDI enterprises | According to international and Vietnamese standards | By scale |
Note: The above price list is for reference only. To receive an accurate quote for tax audit services, MAN needs to conduct a preliminary review of your documents.
Criteria for selecting a reputable tax audit service provider.
With hundreds of auditing firms on the market, how can you choose a reliable partner? Businesses need to consider the following criteria:
- Professional license: The firm must be on the list of qualified auditing firms published annually by the Ministry of Finance.
- Personnel: Auditors must hold CPA (Certified Public Accountant) certification and possess a thorough understanding of the updated 2025 tax regulations.
- Industry experience: Prioritize firms that have previously provided tax audit services to companies in the same industry as yours.
- Confidentiality commitment: Financial and tax information is trade secrets, and the auditing firm must have a strict confidentiality agreement.
- Accountability: A good unit not only provides reports but also works closely with businesses throughout the process of explaining matters to the tax authorities.
Conclude
Tax audit services act as the final "safeguard" helping businesses control risks and ensure sustainable development in an increasingly stringent legal environment. Proactively reviewing data not only saves costs from penalties but also provides absolute peace of mind for business owners to focus on core business activities.
With a team of highly experienced experts possessing in-depth knowledge of Vietnam's tax legal system, MAN – Master Accountant Network proudly stands as a leading provider of tax audit services. We are committed to delivering comprehensive solutions, from bookkeeping review and cost optimization consulting to direct support in explaining matters to relevant authorities.
Service contact information at 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 & CEO MAN – Master Accountant Network, Vietnamese CPA Auditor with over 30 years of experience in Accounting, Auditing and Financial Consulting.
FAQ – Frequently Asked Questions about Tax Audit Services
Can tax audits replace tax settlement with the government?
No. Tax audit services are provided by independent third parties to help businesses prepare as best as possible. The final tax settlement is still handled by the tax authorities, but having an audit report will help speed up the process and reduce errors.
Do small and medium-sized enterprises (SMEs) need tax audit services?
It's absolutely necessary. SMEs often lack professional accounting departments, leading to a very high risk of errors. Auditing costs are a small investment to avoid huge penalties later on.
When is the best time to hire a tax audit service?
It is best to do this annually or at least six months before a tax audit is scheduled.
