Update on how to file taxes online in 2025, easy steps via the internet.

How to file taxes online for merchants and digital-era entrepreneurs is not as difficult as many people think. In an era where online sales are the heart of business, knowing how to manage and file taxes online correctly and quickly is essential for a private business. Whether it's a small shop or a growing business, using the Revenue Department's online website can help reduce the time spent on paperwork and give you more time to develop and expand your business to its fullest potential.

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Article Contents

• What is Personal Income Tax?
• Who is required to file taxes?
• When can you file taxes?
• What documents are needed to file taxes online?
• What is the difference between P.N.D. 90 and P.N.D. 91?
• 8 Steps on How to File Your Tax Return Online
• Results of Filing a Personal Income Tax Return
• Summary of How to Easily File Taxes Online for Entrepreneurs

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What is Personal Income Tax?

Personal income tax is a tax collected by the state from the income of individuals, such as full-time employees, self-employed professionals, or business owners. It is calculated from net income (total income minus legally specified expenses and online tax allowances) according to a progressive tax rate. The higher the income, the higher the tax rate. A personal income tax return must be filed with the Revenue Department within the specified deadline to comply with the law and support the country's development through government tax revenue.

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Who is required to file taxes?

Individuals whose income meets the legally specified threshold are required to file a personal income tax return with the Revenue Department every year, especially in the early part of the year (January–March) following the year the income was earned. The groups of individuals who are required to file personal income tax include:

• Full-time employees with salaries, income, bonuses, or other wages.
• Self-employed professionals such as doctors, lawyers, architects, translators, etc.
• Private business operators or small business owners.
• Freelancers or general contractors who earn income from providing services.
• Those with income from renting out properties such as houses, condos, land, etc.
• Those with income from interest, dividends, or profits from the sale of assets.
• Individuals who have income from abroad but reside in Thailand.
• Individuals who do not reside in Thailand but have income that arises in Thailand.

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When can you file taxes?

Until when can you file taxes online? It's important to first explain that filing personal income tax in Thailand can be done through two channels: regular filing (paper submission) and online filing. Paper filing must be completed by March 31 of each year, covering income from the previous tax year. For online tax filing through the Revenue Department's website, such as the D–MyTax or e-Filing system, the deadline is extended to April 8 of the following year.

Filing taxes online has become more popular today because it is convenient, fast, and allows the use of pre-filled data provided by the Revenue Department, which helps reduce errors. You can also request to pay taxes in installments and check your tax refund status through the system. Taxpayers should choose a suitable online tax payment channel and complete the process within the specified period to avoid fines or penalties for late filing.

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What documents are needed to file taxes online?

Before filing personal income tax online, taxpayers should study how to file taxes online and prepare all necessary documents and important information to ensure a fast process and reduce errors when filling out the form. The documents and information that should be prepared before filing taxes online include:

• Citizen ID number and password for the Revenue Department's system (RD e‑Filing or D‑MyTax).
• Salary certificate (50 Tawi) from the employer (for full-time employees).
• Proof of other income, such as freelance fees, service fees, royalties, rental income, etc.
• Documents for tax deductions, such as life insurance premiums, health insurance, mutual funds (RMF/SSF), home loan interest, donations, spouse and child allowances, etc.
• PromptPay account number linked to the citizen ID card (for tax refunds).
• Tax installment payment documents (if any) if choosing to pay in installments.
• Information on real estate or other assets (if there is income from selling or renting).
• Receipts or withholding tax certificates (if there is income from multiple sources).

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What is the difference between P.N.D. 90 and P.N.D. 91?

The personal income tax return forms P.N.D. 90 and P.N.D. 91 are used for filing personal income tax but are for different situations, depending on the nature of the taxpayer's income. The differences are as follows:

P.N.D. 90

• Used for individuals with various types of income.
• Examples of income requiring this form:

1. Income from salary and other additional income.
2. Income from self-employment (e.g., freelancers, doctors, lawyers).
3. Income from renting out property.
4. Income from selling goods in an online business or private business.
5. Interest, dividends, income from abroad, etc.

• Suitable for those with income under Section 40(2)–40(8) of the Revenue Code.

P.N.D. 91

• Used for individuals with income from salary only.
• Examples of who uses this form:

1. Full-time employees with income from a single employer.
2. No other income besides salary, bonuses, or wages.

• Covers only income under Section 40(1).

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8 Steps on How to File Your Tax Return Online

If you don't need to travel to the Revenue Department office, filing your personal income tax online can be done easily and quickly. Here are 8 steps to file taxes online through the Revenue Department's website. What are they? You can follow them like this:

1. Go to the Revenue Department's website

Go to the website www.rd.go.th to start filing your taxes online. Then click on the "File Online" menu on the homepage.

2. Log in to the Revenue Department's e-Filing system

Log in with your Citizen ID number and the password you registered with. If you are a first-time user, you need to register before using the system.

3. Select to file the P.N.D. 90/91 income tax form

Select either the P.N.D. 90 or P.N.D. 91 form that matches your type of income. The system will then take you to the tax information entry form.

4. Fill in taxpayer information

Fill in your full name, address, and marital status completely. Then check for accuracy before proceeding to the next step.

5. Fill in income

Enter all income received during the tax year, such as salary and supplemental income. You can upload or fill in the information according to the 50 Tawi form from your employer.

6. Fill in deductions

Enter information for deductions such as insurance premiums, funds, home loan interest, Easy e-Receipt, etc. The system will automatically calculate the amount of tax to be paid or refunded.

7. Review the information

The system will display an overview of all the information you have entered for you to review. If there are any errors, you can go back and correct them before confirming.

8. Confirm the submission

Once all information is correct and complete, click "Confirm Submission." You can then choose to pay the tax immediately or request a tax refund via PromptPay linked to your Citizen ID number if you are eligible.

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Results of Filing a Personal Income Tax Return

There are two main outcomes from filing a personal income tax return: a case where there is no additional tax to be paid or an overpayment, and a case where there is additional tax to be paid after filing. They are as follows:

• Case of no tax due or overpaid tax

1. This means you have prepaid your taxes or your withholding tax was more than what you actually owe.
2. You are entitled to a tax refund from the Revenue Department, which can be received via PromptPay linked to your Citizen ID number or by bank transfer.
3. The Revenue Department will process the verification and transfer the refund within a specified period.

• Case of additional tax due

1. This means the withholding tax or prepaid tax does not cover the total amount of tax you need to pay.
2. You must pay the remaining amount to the Revenue Department within the specified deadline.
3. If payment is late, there may be additional interest or penalties according to the law.
4. You can opt for installment payments in some cases as determined by the Revenue Department.

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Summary of How to Easily File Taxes Online for Entrepreneurs

How to file personal income tax online is easy and convenient through the Revenue Department's website. Start by logging into the e-Filing system, selecting the P.N.D. 90 or 91 form, entering your income and deduction information, verifying its accuracy, and confirming the submission within the specified deadline. This helps reduce hassle and save more time for taxpayers.

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References

1. Personal Income Tax Guide. (September, 2018). The Revenue Department. https://www.rd.go.th/fileadmin/download/insight_pasi/personalincome_61.pdf