How to prepare a corporate income tax finalization declaration for 2025 helps businesses complete their tax obligations accurately, transparently and in compliance with the law. The article provides detailed step-by-step instructions from summarizing revenue, expenses, determining taxable income, to filling out the declaration and creating accompanying appendices. At the same time, it shares important notes, common errors and practical examples, helping accountants easily apply and optimize the tax finalization process.
Overview of corporate income tax finalization declaration
In financial management and accounting activities, the final settlement declaration corporate income tax is one of the most important documents, reflecting comprehensively the business results and tax obligations of the enterprise in the fiscal year. Every accountant needs to clearly understand the nature, role and related legal regulations to prepare correctly and fully according to the requirements of the tax authority.
This section will help you have an overview of the corporate income tax finalization declaration, from concept, purpose, legal basis to applicable subjects - as a foundation for mastering how to prepare an accurate and effective corporate income tax finalization declaration in 2025.
What is corporate income tax finalization declaration?
Declaration corporate income tax settlement is a mandatory document that businesses must prepare and submit to the tax authorities every year. This is the basis for determining the amount of corporate income tax (CIT) to be paid or refunded during the tax period. Understanding how to prepare a CIT finalization declaration helps accountants ensure transparent tax records, avoid errors, and at the same time demonstrate the business's compliance with the law.
This declaration summarizes all the results of production and business activities, revenue, expenses, profits and losses and adjustments according to regulations. Through this, the tax authority can check the tax obligation performance of the enterprise in the fiscal year.
Purpose and role of settlement
Corporate income tax finalization is the final step in the accounting and tax process chain of a fiscal year. The objectives of preparing and submitting the declaration are:
- Determine the exact amount of corporate income tax payable, exempted, reduced or transferred to the next period.
- Review costs, revenue, and profits to accurately reflect the business's financial situation.
- Help businesses correct errors during the year and prepare data for the next period.
Mastering how to prepare corporate income tax finalization declarations not only helps businesses avoid being fined for incorrect data but is also the basis for optimizing legal profits.
Legal basis related to corporate income tax finalization declaration
To ensure the correct preparation and submission of declarations, accountants need to have a clear understanding of the current legal bases. This is an important basis to help businesses prepare the 2025 corporate income tax finalization declaration accurately, comply with the law and avoid risks during the post-finalization audit process.
| STT | Legal documents | Main content / Scope of application |
| 1 | Tax Administration Law No. 38/2019/QH14 | Regulates the principles of tax management, rights and obligations of taxpayers, and the authority of tax authorities in inspection, examination, and sanctioning. It is the highest legal basis for the implementation of corporate income tax finalization declaration. |
| 2 | Decree 126/2020/ND-CP | Detailed instructions for implementing the Law on Tax Administration, including regulations on tax declaration dossiers, submission deadlines, forms of declaration and submission of corporate income tax finalization declarations. |
| 3 | Circular 80/2021/TT-BTC | Provide specific instructions on how to declare, pay and finalize corporate income tax; issue form 03/TNDN and attached appendices. This is the main document that accountants need to base on to prepare the corporate income tax finalization declaration for 2025. |
| 4 | Decree 132/2020/ND-CP | Regulations on tax management for enterprises with related-party transactions, including principles of declaration, determination of related-party transaction prices and obligations to prepare price determination dossiers. |
Subjects required to make corporate income tax finalization declaration
According to the provisions of current tax law, all organizations and enterprises that conduct production and business activities with taxable income in Vietnam are obliged to prepare annual corporate income tax finalization declarations. Specifically including:
Vietnamese Enterprises
Including joint stock companies, limited liability companies, partnerships, private enterprises... whose business activities generate profits or losses during the tax period.
Foreign Direct Investment (FDI) Enterprises
Joint venture companies and foreign-invested 100% companies in Vietnam, regardless of profit or loss, must prepare corporate income tax finalization declarations to report to the Vietnamese tax authorities.
Cooperatives, economic organizations, and public service units with production and business activities
These organizations generate taxable income from production, service business or commercial activities, and must declare and submit corporate income tax finalization declarations according to regulations.
Special cases
In addition to the usual business entities, there are still some special cases that businesses need to pay attention to. These cases require the preparation of a corporate income tax finalization declaration for the actual operating period during the year, to ensure full, accurate declaration and compliance with tax laws. The table below summarizes the special cases with brief instructions on the corresponding declaration obligations:
- Enterprises dissolved or ceased operations during the year: must prepare a declaration for the period of operation;
- Enterprises merging or converting their types (for example, from a limited liability company to a joint stock company): must prepare a corporate income tax finalization declaration corresponding to the tax period of the operating period;
- Enterprises temporarily suspend business but have taxable income: still have to make a declaration.
Current corporate income tax finalization declaration form
Currently, enterprises use form No. 03/TNDN issued with Circular 80/2021/TT-BTC. The declaration form includes the following main parts:
- Taxpayer information;
- Results of production and business activities;
- Adjustments to increase or decrease taxable income;
- Taxable income and corporate income tax payable.
In addition to the main declaration, businesses need to prepare detailed appendices. Understanding the form structure is an important first step in preparing a corporate income tax finalization declaration in accordance with regulations.
Prepare data and documents before making a declaration
Before filling out the corporate income tax declaration, preparing complete and accurate documents and vouchers is an extremely important step. This is the foundation to help accountants ensure that the declared data matches the financial reports, avoiding errors and risks of being penalized by the tax authorities. The types of documents and data that need to be prepared include:
| STT | Profile / Data | Content / Role |
| 1 | Annual financial report | Including Balance Sheet, Income Statement and related report appendices. It is the main basis for determining revenue, expenses, profits and tax adjustments. |
| 2 | Detailed accounting books | Including detailed books of revenue, expenses, debts, and fixed assets. The data must match the financial statements and declarations, ensuring the correct preparation of the corporate income tax finalization declaration. |
| 3 | Legal documents and invoices | Including VAT invoices, payment documents, contracts, delivery and receipts... Verify deductible and non-deductible expenses when making the declaration. |
| 4 | Appendix attached to the declaration | – Loss carryover appendix: Records the amount of losses carried over from previous years.
– Tax incentive appendix: Applicable if the enterprise enjoys special incentives according to priority projects or sectors. |
| 5 | Table of deductible and non-deductible expenses | Classify expenses based on the provisions of the Corporate Income Tax Law and guiding Circulars. Help accountants review, avoid incorrect recording, ensure accurate and transparent preparation of corporate income tax finalization declarations. |
Deadline and place for submitting declaration
Enterprises need to clearly understand the deadline and location for submitting declarations to ensure compliance with legal regulations, avoid late submission and risk of being fined.
| Content | Detail |
| Submission deadline | No later than 90 days from the end of the fiscal year |
| Submission location | – Via the Electronic Tax Portal (eTax) or
- Submit directly to the Tax Department managing the enterprise |
| Note when submitting | Submit the complete main declaration and all accompanying appendices; check that the figures match the financial statements and accounting books. |
Detailed instructions on how to prepare corporate income tax finalization declaration
Preparing a corporate income tax (CIT) finalization declaration is an important step to help businesses accurately determine the amount of tax payable or refunded in the fiscal year. This is not only a mandatory declaration obligation according to the provisions of the Law on Tax Administration and Circular 80/2021/TT-BTC, but also a basis for tax authorities to inspect and evaluate the effectiveness of production and business activities of enterprises. However, in reality, many accountants still encounter difficulties in implementation due to the complexity of forms, indicators and accompanying appendices.
The following article will provide detailed instructions on how to prepare corporate income tax finalization declarations according to the latest regulations in 2025, helping businesses to easily implement, limit errors and ensure compliance with tax laws.
Step 1: Determine the tax period and summarize revenue
To start preparing a corporate income tax return, the first step is to determine the tax period and fully summarize all revenue generated during the period.
- The corporate income tax period is usually the calendar year (from January 1 to December 31).
- Enterprises need to summarize all revenue generated during the period from sources: sales, service provision, financial activities, import and export...
- Check revenue matching on detailed accounting books and financial statements to ensure accurate figures.
This is the fundamental step to prepare a corporate income tax declaration, because revenue is the basis for calculating taxable income.
Step 2: Determine deductible and non-deductible expenses
After summarizing revenue, the next step in the process of preparing the corporate income tax declaration is to identify and classify expenses according to the provisions of the Corporate Income Tax Law. This is an important step to help businesses calculate the correct taxable income and tax payable.
- Deductible expenses: Are expenses that directly serve production and business activities and have legal documents, paid in accordance with regulations; These expenses will be deducted from revenue to determine taxable income; For example: raw material costs, labor costs, depreciation of fixed assets, premises rental costs, legal business management costs, etc.
- Non-deductible expenses: Are expenses that are not directly related to production and business activities or do not have legal documents; For example: personal expenses, administrative fines, expenses for purchasing assets that do not serve production and business, unacceptable expenses exceeding the norm, etc.
Step 3: Calculate taxable income
After determining revenue and classifying expenses, the next step is to calculate taxable income, that is, the actual profit of the enterprise subject to corporate income tax. This is the core step to accurately determine the amount of tax payable.
Basic formula:
|
Taxable income = Revenue – Deductible expenses + Other income – Tax exemptions and reductions |
In there:
- Revenue: Total revenue generated during the period from business activities, finance, import-export...
- Deductible expenses: Legal expenses for production and business, classified in the previous step.
- Other income: Includes profits from irregular activities, asset valuation differences, dividends received, etc.
- Tax exemptions and reductions: Apply according to current tax incentives (if the enterprise is eligible).
Step 4: Calculate corporate income tax payable and provisional tax paid
After determining taxable income, the next step is to calculate the amount of corporate income tax payable for the year and compare it with the amount of tax provisionally paid. This is an important step to accurately determine the final tax liability of the enterprise.
Enterprises must apply the current corporate income tax rate, usually 20% on taxable income. In some special cases, enterprises enjoy tax incentives, the applicable tax rate may be lower according to regulations, such as investment projects or priority sectors. The amount of corporate income tax payable is calculated according to the formula:
|
Corporate income tax payable = Taxable income x Tax rate |
During the fiscal year, enterprises usually have provisionally paid corporate income tax quarterly or monthly. Therefore, after calculating the corporate income tax payable, accountants need to compare it with the amount of tax provisionally paid. Through this comparison, enterprises will determine the remaining tax payable if the total amount of provisionally paid tax is lower than the actual tax amount. Conversely, if the enterprise has overpaid, the excess provisionally paid tax will be refunded by the tax authority.
Performing this step correctly helps businesses complete the settlement of corporate income tax obligations in a transparent manner, avoiding underpayment or overpayment of tax. This is also an important step to ensure that the corporate income tax declaration is prepared in accordance with the law, and at the same time creates a basis for comparison and inspection when the tax authority conducts an inspection.
Step 5: Fill out the corporate income tax finalization declaration (Form 03/TNDN)
After preparing all the data, the accountant will proceed to fill out the corporate income tax finalization declaration according to Form 03/TNDN. This is an important step, because all the data on revenue, expenses and taxable income will be shown on the declaration.
Basic information to be filled in includes business information (name, tax code, address), revenue, expenses, taxable income, and corporate income tax payable, amount paid or amount to be paid/refunded.
All figures must match the financial statements and accounting books to avoid errors. Filling out the declaration accurately helps businesses comply with the law, be transparent and reduce risks when tax authorities inspect.
Step 6: Prepare and attach appendices to the declaration
After completing the main declaration, the enterprise needs to prepare and attach appendices to the declaration. These appendices help the tax authority check and compare data and ensure transparency in the tax settlement process.
Some important annexes include the loss carryforward annex, which records losses carried forward from previous years, helping businesses reduce their taxable income for the current year. The tax incentive annex only applies to businesses that enjoy special incentives according to priority projects or sectors, to record legitimate tax reductions.
In addition, there may be other appendices such as determining deductible expenses, other income or revenue from related transactions if the enterprise incurs these amounts. Preparing complete and accurate appendices helps increase transparency, reduce errors and facilitate tax inspections.
Step 7: Check and submit the declaration
After completing the declaration and preparing the appendices, the final step is to check, compare the data and submit the declaration to complete the corporate income tax settlement accurately and transparently.
- Cross-check all data: revenue, expenses, taxable income, tax payable.
- Submit electronic declaration via Tax Portal (eTax) or directly at the Tax Department managing the enterprise.
- Store documents, accounting books and financial reports for future comparison, inspection or examination. Write the introduction of the paragraph.
Appendices attached to corporate income tax finalization declaration
On the corporate income tax finalization declaration, enterprises need to prepare and attach appendices for the tax authority to check, compare and ensure transparency. These appendices help to fully record the expenses, income and tax incentives that the enterprise enjoys.
| Appendix name | Content | Role |
| Appendix to transfer losses | Record losses carried forward from previous years | Helps reduce current year's taxable income |
| Tax incentive appendix | Applicable when businesses enjoy tax incentives according to priority projects or sectors. | Record legitimate tax deductions |
| Appendix to deductible expenses | Identify legitimate expenses that are deductible under regulations | Ensure legal and transparent costs when making declarations |
| Other income appendix | Identify income items that are not part of the main revenue but are subject to tax | Ensure taxable income is fully recorded |
| Appendix to revenue from related transactions | Recognition of revenue arising from transactions with related parties | Assist tax authorities in examining transfer pricing and related tax obligations |
Common errors when preparing corporate income tax finalization declaration
When preparing corporate income tax returns, accountants often encounter some common errors. Recognizing and avoiding these errors helps ensure that the returns are accurate, transparent, and in compliance with the law.
| Common errors | Reason | Consequence |
| Revenue and cost figures do not match | Poor reconciliation between accounting books and financial statements | Tax payable error, risk of being punished by tax authorities |
| Missing or incorrect business information | Missing name, tax code, address | The tax authority refused to accept the declaration. |
| Failure to establish or incorrectly establish the attached appendix | Ignore loss transfer appendix, tax incentives, deductible expenses | Taxes are not reduced properly, lack of transparency in inspection |
| Wrong corporate income tax calculation | Failure to apply correct tax rate, omission of increase/decrease adjustments | Underpayment or overpayment of tax must be adjusted later. |
| Late submission of declaration | Not keeping track of submission deadlines | Late payment penalty, may be charged late interest |
| Error in filling out provisional tax information | Not compared with temporary documents submitted during the year | The tax payable or refund is incorrectly calculated. |
Example illustrating how to prepare corporate income tax finalization declaration
To make it easier to visualize, let's say ABC Company Limited end fiscal year 2025 with the following figures: revenue of 10 billion VND, deductible legal expenses of 6 billion VND, other income of 500 million VND and no tax incentives. During the year, the company temporarily paid 800 million VND in corporate income tax. First, the accountant determined taxable incomeAccording to the formula:
|
Taxable income = Revenue - Deductible expenses + Other income - Tax exemptions and reductions |
Applying data from ABC company:
|
10,000,000,000−6,000,000,000+500,000,000=4,500,000,000 VND |
So the company's taxable income is 4.5 billion VND. Next, the accountant calculates the corporate income tax payable. Applying the tax rate 20%:
|
4,500,000,000×20%=900,000,000 VND |
Compared with the provisional tax payment of 800 million VND, the company still has to pay an additional 100 million VND to the tax authority. When filling out the corporate income tax finalization declaration (Form 03/TNDN), the accountant enters the company's basic information, data on revenue, expenses, taxable income and corporate income tax payable. At the same time, prepare the accompanying appendices, for example, the appendix of loss transfer if any, or the appendix of deductible expenses and the appendix of other income.
Finally, before submitting, the accountant reviews all data, compares it with the financial report and detailed accounting books to ensure accuracy. After confirming accuracy, the declaration is submitted via the Electronic Tax Portal (eTax). Relevant documents and reports are fully archived for future inspection or audit.
Through this example, we can clearly see each step in preparing a corporate income tax declaration, from summarizing data, calculating taxable income, determining tax payable, to filling out the declaration and submitting it to the tax authority. Following the correct steps will help businesses be transparent, accurate and in compliance with legal regulations.
Conclude
How to prepare a corporate income tax finalization declaration is an important step to help businesses complete their tax obligations accurately and transparently. Fully implementing the steps from summarizing data, calculating taxable income, to filling out the declaration and creating the accompanying appendices will help avoid errors, reduce the risk of being fined and ensure compliance with the law.
Preparing a corporate income tax finalization declaration is not only a legal obligation but also an opportunity for businesses to review all financial activities during the year. Good control of revenue, expenses and tax incentives helps to optimize legal profits and improve financial management efficiency. Therefore, mastering the process and applying support tools is extremely necessary.
Ultimately, properly completing your corporate income tax return helps your business maintain transparent tax records, ready for audits, inspections, or reconciliations when needed. Make sure every step is taken carefully, and take advantage of the support from our experts. MAN – Master Accountant Network to make the tax settlement process fast, accurate and efficient.
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
