Annual Audit in Vietnam 2026: Requirements, Deadlines, Costs and Penalties for Businesses

If you are a foreign business owner in Vietnam, the annual audit may already feel like part of year-end. Your accountant closes the books, an external team requests evidence, figures move, and an audit report is attached to the financial statements.

The process can look procedural. In reality, it tests whether the financial story of the business is supported by evidence and presented under the correct Vietnamese accounting framework.

This matters even for a small foreign-invested company. Low revenue, a loss or a small team does not automatically remove the obligation. In 2026, mandatory audits also cover certain large domestic enterprises. The legal basis comes from the Law on Independent Audit, as amended by Law 56/2024/QH15, and Decree 90/2025/ND-CP.

What is an audit in Vietnam?

An independent audit is an examination by a licensed external firm. The auditor gathers evidence and opines on whether the financial statements are presented fairly, in all material respects, under the applicable accounting framework.

It is not bookkeeping. Management remains responsible for the accounts and financial statements. It is also not a tax inspection, and a clean opinion does not mean the tax authority has approved every invoice, expense or tax position.

The main audit types can be understood in two ways.

By the party performing the work:

• State audit: focuses mainly on public finance and public assets.
• Independent audit: performed by an eligible external firm under contract. This is the annual audit most foreign-invested businesses encounter.
• Internal audit: reviews governance, risk and controls inside an organization. It does not replace a statutory independent audit.

By what the engagement examines:

• Financial statement audit: assesses whether the statements are fairly presented in all material respects.
• Compliance audit: assesses compliance with laws, contracts or rules.
• Operational audit: assesses economy, effectiveness and efficiency.

For most private businesses, "annual audit" means an independent audit of annual financial statements.

Which businesses must be audited in Vietnam?

The most important groups include:

• Foreign-invested enterprises. A Vietnamese enterprise with foreign investment generally requires an annual independent audit, without a minimum revenue or employee threshold.
• Credit institutions, including foreign bank branches operating in Vietnam.
• Financial institutions, insurance and reinsurance businesses, insurance brokers and relevant foreign insurance branches.
• Public companies, issuing organizations and securities businesses.
• State-owned enterprises, subject to the statutory exceptions for activities involving state secrets.
• Entities undertaking nationally important projects or Group A projects using state funds, for the required audit of completed-project finalization reports.
• Certain entities with State capital and other projects using State funds, as provided by the Government.
• Audit firms and Vietnamese branches of foreign audit firms, which must themselves be audited annually.
• Other entities required by sector-specific law, plus businesses audited voluntarily for an investor, lender, parent company or contract.

The 2026 change for large enterprises

From 1 January 2026, the amended law expressly includes other large-scale enterprises in the mandatory annual-audit group. Under Decree 90/2025, a business falls within this group when it satisfies at least two of these three tests, measured using the preceding year's data:

• average annual employees participating in social insurance: more than 200;
• annual total revenue: more than VND 300 billion;
• total assets at financial year-end: more than VND 100 billion.

Businesses meeting the tests using 2024 data must be audited from the 2025 financial year onward. A business in this category leaves it after failing the tests for two consecutive years, until it qualifies again.

These thresholds do not exempt foreign-invested companies, which fall within a separate statutory category.

Why does the annual audit matter?

The immediate answer is compliance. An entity subject to mandatory audit must attach the audit report when submitting or publicly disclosing its financial statements.

Audited accounts give shareholders, lenders, buyers and overseas parents a credible view of the business. During fundraising, refinancing or due diligence, a consistent audit history reduces time spent rebuilding old records.

It can expose weaknesses before they become expensive, including unsupported expenses, unreconciled balances, inaccurate inventory, related-party transactions, foreign-contractor tax and revenue-recognition problems.

An audit provides reasonable assurance, not a guarantee. Auditors use materiality, risk assessment and testing. They do not verify every transaction, guarantee that fraud does not exist or replace management's responsibility.

What does an annual audit report assess?

The auditor examines evidence supporting the figures and disclosures, including revenue, expenses, cash, receivables, payables, inventory, fixed assets, loans, equity, taxes, payroll, related parties, provisions, commitments and events after year-end.

The auditor also considers management's accounting policies and estimates, going concern, overall presentation and material disclosures. Internal controls inform audit planning, but the annual opinion is on the financial statements, not a separate certification that every control is effective.

The report identifies the statements, respective responsibilities and basis of work, then gives one of four opinions:

• Unmodified: the statements are fairly presented in all material respects.
• Qualified: a material issue exists, but it is limited rather than pervasive.
• Adverse: material and pervasive misstatements make the statements unreliable as a whole.
• Disclaimer of opinion: the auditor could not obtain enough appropriate evidence and the possible effect could be material and pervasive.

A separate management letter may describe control weaknesses and recommendations, but it is not the audit opinion.

Annual audit timeline in Vietnam

The legal deadline starts early. A mandatory-audit business must sign its audit contract no later than 30 days before its annual accounting period ends. For a 31 December year-end, January is already too late.

A sensible working sequence is:

1. Before year-end: confirm scope, select an eligible firm, sign the contract and receive the information request list.
2. Around year-end: complete cash and inventory counts, with auditor observation where required.
3. After closing: finalize the ledger, reconciliations, tax schedules and draft statements.
4. Fieldwork: answer questions, obtain confirmations and resolve adjustments and missing evidence.
5. Signing and filing: management signs the statements, the auditor signs the report, and the package is filed.

Under Circular 99/2025/TT-BTC, businesses applying the full enterprise accounting regime generally submit annual financial statements within 90 days after year-end. For a company using the calendar year, the usual deadline is therefore 31 March of the following year. The audit report is submitted together with the annual financial statements, so the audit normally must be completed by the same end-of-March deadline. Regulated and public-interest entities may face additional or earlier deadlines.

Circular 99 applies to financial years beginning on or after 1 January 2026 and replaces Circular 200 under the main enterprise regime. SMEs using another regime should confirm their applicable framework.

How much does an audit cost?

Vietnam has no standard annual-audit price. Fees may be based on auditor time, a fixed service fee or a multi-period contract with a fixed fee for each period.

In practice, a quote depends on the company's size, transaction volume, locations, industry, bookkeeping quality, inventory, group reporting, related-party dealings, deadline and expected cleanup work.

The cheapest quote is not always the lowest-cost outcome. Ask what is included, who leads the fieldwork, whether inventory observation and group reporting are covered, and how extra work is priced.

What documents should the business prepare?

Most annual audits need:

• Corporate registrations, investment certificate if applicable, charter, licenses and amendments.
• Trial balance, ledger, sub-ledgers and draft financial statements with notes.
• Bank and cash records, reconciliations and confirmation details.
• Receivable and payable aging, contracts and confirmation contacts.
• Inventory counts, fixed-asset register and supporting purchase records.
• Contracts, e-invoices, delivery or acceptance evidence and major expenses.
• Payroll, labor, personal income tax and social insurance records.
• Tax filings and reconciliations, including VAT, corporate income tax and foreign-contractor tax.
• Capital, loans, related-party and transfer-pricing documents where relevant.
• Governance minutes, legal claims, commitments and prior audit findings.

Assign one person to the request list and reconcile every schedule to the ledger before sending it. This avoids repeated questions about the same discrepancy.

Penalties for failing to complete a mandatory audit

The current penalty framework is Decree 228/2025/ND-CP, effective 18 August 2025.

Failure to perform a mandatory audit can attract a VND 40 million to VND 50 million fine. Signing the annual audit contract late can attract VND 10 million to VND 20 million. An ineligible provider, restricted scope or misleading information can trigger separate, potentially higher penalties.

The operational consequences can be worse. The company may be unable to complete its filing, satisfy a lender or parent, finish due diligence or explain unresolved balances in a later tax inspection.

Practical points to get right

• Check the audit firm's status. Verify the provider against the Ministry of Finance's current list of eligible audit firms. A foreign certificate or international brand alone does not authorize a Vietnamese statutory audit signature.
• Do not wait for perfect books. Appoint the auditor early, identify gaps and agree a closing timetable. Delay can prevent inventory observation or efficient evidence collection.
• Keep audit and tax assurance separate. The audit may identify tax risks, but it does not settle the company's tax position with the authorities.
• Address prior-year findings. Repeated unreconciled balances or unsupported entries can become harder to fix and may affect the opinion.
• Watch related-party and cross-border items. Management fees, royalties, loans, foreign services and capital contributions need consistent accounting, tax and legal support.
• Plan for the 2026 accounting transition. Companies moving to Circular 99 should align policies, account mappings, comparative information, financial-statement formats and internal accounting rules before year-end.
• Rotate the signing auditor when required. A practising auditor may not sign reports for the same audited entity for more than five consecutive years, even if the business retains the same audit firm.

The bottom line

For a foreign-owned business in Vietnam, the annual audit should begin with clear scope, an eligible auditor, reliable monthly accounting and a realistic closing calendar, not a frantic search after year-end.

Done properly, the audit gives owners a disciplined view of what the accounts can prove, what remains exposed and what should be fixed before the next investor, bank, buyer or authority asks.

This article provides general information and is not legal, tax or accounting advice. Audit obligations and filing requirements can vary by entity type, sector, ownership, accounting period and regulatory status. Confirm your company's position with a qualified professional in Vietnam.