Online tax filing software has become an indispensable "assistant" for the Vietnamese accounting, auditing, and business communities. The application of technology to tax management is a mandatory requirement. Tax Administration Law No. 38/2019/QH14, This helps to increase data transparency and bridge the gap between taxpayers and tax authorities. According to the General Department of Taxation, as of early 2026, more than 991 businesses had implemented electronic tax declarations, minimizing manual errors and optimizing financial operating costs.
The release of HTKK version 5.6.1 on March 17, 2026, demonstrates the government's efforts to adapt to new legal changes such as Circular 99/2025/TT-BTC. Understanding how online tax filing software works helps accountants closely monitor tax obligations and avoid potential penalties. Decree 125/2020/ND-CP. This article provides a comprehensive overview of the current tax software ecosystem, from HTKK to the most modern mobile applications.
What is HTKK software and why do I need to update to version 5.6.1?
The HTKK software is an important tool that supports businesses in filing taxes correctly according to the regulations of the tax authorities. Updating to a new version like 5.6.1 not only helps fix technical errors but also ensures that the declared data is accurate and consistent with current tax policy changes.
Overview of the Tax Declaration Support (HTKK) application
HTKK stands for "Tax Declaration Support," a free application released by the General Department of Taxation. It is one of the most popular online tax declaration software programs, allowing taxpayers to create declarations with standardized barcodes for submission via the electronic portal or directly at the tax authority. This application ensures consistency in data format according to current regulations.
New features in HTKK version 5.6.1 (Updated March 17, 2026)
Updating online tax filing software to the latest version is a mandatory technical requirement to ensure algorithm accuracy. Version 5.6.1 focuses on addressing the following issues:
- Settlement declaration form 05/QTT: Fix the loading error for indicator 22 (Total number). personal income tax (deducted) from the Excel spreadsheet into Appendix 05-1/BK-TNCN.
- Declaration Form 03/TNDN: Adjust the logic for checking indicator C5 (Science and Technology Fund Allocation). The inspection rate has been increased from 10% to 20% compared to indicator C4, in line with policies encouraging investment in new technologies.
- Administrative area: Updating the list of new administrative units in Lao Cai, Tuyen Quang, and Quang Ninh according to the Resolution of the Standing Committee of the National Assembly.
Top most popular online tax filing software currently available.
Below is a detailed comparison table of the most popular tax filing tools in 2026:
| Criteria | HTKK software | eTax Portal | eTax Mobile |
| Type | Software installation (Offline) | Web browser platform | Mobile application (App) |
| Object | Business, Accounting | All taxpayers | Individuals, Household businesses |
| Advantage | Handling large, complex data | Submit the declaration form in person, via T-VAN. | Flexible, pay taxes 24/7 |
| Disadvantages | Manual updates are required. | Network speed is dependent. | Support for simplified declaration forms |
Using a combination of online tax filing software helps businesses create a closed-loop process from data preparation to tax return submission and payment.
Detailed instructions for installing and using HTKK 5.6.1
To use HTKK 5.6.1 effectively, businesses need to understand the configuration requirements and the software installation or upgrade process. Doing it correctly from the start will help minimize errors and ensure that the tax declaration process is quick and accurate.
Computer configuration requirements
To run online tax filing software smoothly, your computer needs to meet the following requirements:
- Operating system: Windows 10 or Windows 11 (MacOS is not supported).
- Required software: .NET Framework 3.5 or later.
- Memory: A minimum of 1GB of free space is required for the installer and database.
Setup process for new businesses
For organizations using online tax filing software for the first time, please follow these steps:
- Access the General Department of Taxation's website to download the installation package.
- Unzip and run the file. setup.exe with Administrator privileges.
- Declare business information (Tax Identification Number, Address, Tax Authority).
- Regularly back up your data to avoid losing important information.
How to upgrade from an older version (HTKK 5.xx to 5.6.1)
Users of online tax filing software can perform quick automatic upgrades. When opening the old application, the system will display a message saying, "A new version is available, would you like to update?". Select "Yes" and wait a few minutes for the system to automatically download the latest update package.
Tax declaration process for household businesses on HTKK.
Applying online tax declaration software for household businesses has become simpler with Form 01/CNKD. The process consists of 4 steps:
- Step 1: Log in to HTKK using your business's tax identification number (MST).
- Step 2: Select the "Taxes for household businesses and individuals" section and find form 01/CNKD.
- Step 3: Enter the actual revenue generated (the software will automatically apply the applicable rate). VAT and personal income tax).
- Step 4: Generate the XML file to submit to the e-Tax system.
Accountants should carefully check the figures in the tax reduction appendix (if any) in accordance with the current economic support resolutions of the Government.
Optimize your tax management with AMIS Personal Income Tax and mTax solutions.
Besides the online tax declaration software provided by government agencies, many businesses have switched to integrated solutions like MISA AMIS. Its strength lies in its ability to connect directly (T-VAN) with the General Department of Taxation. Data from accounting software is automatically transferred to the tax return, completely eliminating manual data entry errors.
Using integrated online tax filing software helps minimize the risk of being subject to back taxes during audits. The AMIS Personal Income Tax subsystem supports the issuance of electronic withholding certificates in accordance with Decree 123/2020/ND-CP, helping to manage personnel records professionally and consistently.
Conclude
Online tax filing software plays a crucial role in corporate financial management. Mastering this tool helps accountants complete their tasks and build a clean data foundation for tax settlements. In the context of constantly changing tax regulations, choosing a professional partner is the most sustainable solution.
At MAN – Master Accountant Network, we offer a comprehensive ecosystem of services: auditing services, tax accounting, in-depth tax consulting, settlement and tax reporting. With a team of experienced experts, MAN is committed to helping businesses optimize their tax payments and reduce legal risks. Let MAN handle the complexities of online tax filing software, allowing you to focus on business development.
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.
Frequently Asked Questions about Tax Filing Software
This is due to a permissions error. Right-click the icon and select "Run as administrator." Also, check if your antivirus software is blocking the application.
The HTKK and eTax applications from the General Department of Taxation are completely free. However, T-VAN services or digital signatures (Tokens) will incur licensing fees from the providers.
Yes, it's possible. You need to use the Backup/Restore function to synchronize data between different devices. Why can't I open the HTKK software after installation?
Are there any fees for online tax filing software?
Can I use HTKK on multiple computers for the same tax identification number (MST)?
