Thailand tax calculator 2021 (Download)

Download the free Thailand tax calculator and calculate your personal income tax accurately and with ease. No more dreading seeing your tax bill! Available for both Excel and Numbers.

Juraj Micka

The downloads are contained in a .zip file and are best downloaded on a computer rather than a mobile device.
The Excel version suitable for both Windows and macOS, the Numbers only for macOS.

Simple spreadsheet for individuals with (self)employment income

As a simple, easy-to-use spreadsheet, this Thai personal income tax calculator is perfect for those working and earning ordinary income in Thailand, Thais and expats alike.

While it’s designed for individuals with a regular monthly income from employment (or self-employment), you can customise it to fit your specific financial needs. For example, to accommodate multiple income sources, your investments etc.

Easy to use

Insert your numbers, and the personal income tax will be calculated for you.


Designed for use in Thailand and up to date with the latest tax laws.


It can be customised to match your needs.

Why calculating your tax pays off

Since you are here, it shows that you are ready to take your personal tax matters into your hands, and I applaud you.

Whether you file your own return or let your employer do it for you, knowing how to calculate your income tax can pay dividends in many ways. For instance, it can help you:

  • Prevent ugly surprises during the next tax-filing season (you will have known your tax bill all along)
  • Uncover inaccuracies and payroll mistakes made by your HR
  • Avoid overpaying tax by anticipating your tax bill and knowing how much you need to contribute each month

This goes to show that spending a few minutes each month is worth it and can even save you money. Now let’s look at how to use the calculator for calculating your income tax.

How to use the tax calculator to calculate your personal income tax

Calculating your personal income tax in the calculator is easy. Here’s how to use it.

In the spreadsheet, all fields that require your input have a grey background. On the other hand, all white fields do the calculations automatically and are best left alone (unless you want to change the formulas).

The fields you will have to fill in with your information are:

Gross income

Type in your monthly income before any deductions are taken.

Withholding tax

Tax applied to employment income and can amount to 5-35% of your monthly salary. The deducted amount goes directly to the government. It counts toward your yearly tax liability, meaning you contribute to your total tax bill each month.

Social security

It is an amount paid to the Social Security Fund and makes up 5% of monthly income but no more than 750 THB.

Expenses and savings (voluntary)

With monthly expenses filled in, you can get a clear picture of where your money goes and how much you were able to save.

Deductions and personal allowance

These are trickier to tell and depend on your personal situation, for example, whether you are married and have kids or your income type. For the completeness of information, here’s a list of all possible deductions and allowances:

Tax deductions
Type of Income Deduction
Income from employment 50% (not more than 100,000 THB)
Income from copyrights 50% (not more than 100,000 THB)
Income from property 10% – 30%
Income from liberal professions 30% (medical profession 60%)
Income derived from contract of work whereby the contractor provides essential materials besides tools Actual expense or 70%
Income derived from business, commerce, agriculture, industry, transport, or any other activities not specified earlier Actual expense or 65-85% (depends the type of income)
Personal allowance
Type of allowance Amount
Single taxpayer 60,000 THB for the taxpayer
Undivided estate 30,000 THB for the spouse
Non-juristic partnership or body of persons 30,000 THB for each (max 60,000THB)
Spouse allowance 60,000 THB
Child allowance 30,000 THB each
Parents allowance (parents over 60 years of age with income less than 30,000 THB) 30,000 THB each
Life insurance Max. 100,000 THB each
Health insurance Max. 15,000 THB
Approved provident fund contributions and/or Retirement mutual fund contributions Max. 500,000 THB (not more than 15% of income)
Long term equity fund Max. 500,000 THB (not more than 15% of income)

Tax calculation

The last step – calculating your tax – happens automatically. At the bottom, you will see the total tax due and the amount your employer has withheld from you. These two numbers are then added up.

If the total is positive, you owe tax and will need to pay the remaining balance. In case of a negative result, you have overpaid. You can get your money back from the Revenue Department when filing your taxes – this is called a tax refund.

Where to file a tax return in Thailand

Once you have calculated your tax with the tax calculator, you can file your tax return online on this website or using the official government app. Note that this website is in Thai and is, therefore, pain to use for foreigners. I recommend using the app as it’s easier to use.

For more information about how to file your tax in Thailand, check out this article.

In any way, individual taxpayers in Thailand must file their personal income tax returns and make payments to the Revenue Department within the last day of March following the taxable year. Happy calculating and tax return filing!

Deadline for filing last year’s tax return

The deadline for filing your taxes online for the previous year (2020) is April 07, 2021. Time remaining:


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