Thai Bonus Tax: The Two Legal Methods

Bonuses are taxable income, but Thai law offers two calculation methods — you may choose the cheaper one.

Method 1 — Lump-Sum Calculation

1. Divide the bonus by 12 = monthly average
2. Multiply by 12 = annualized amount → find the progressive tax bracket
3. Apply that rate to the whole bonus

Method 2 — Combined with Salary

1. Calculate tax on (annual salary + bonus)
2. Subtract tax on annual salary alone
3. The difference = bonus tax

Example

100,000 THB bonus, 500,000 THB annual salary:

• Lump-sum: bonus average 8,333/month → effective rate ~5-10% → tax ~5,000-10,000
• Combined: tax(600,000) − tax(500,000) = difference
• Choose the lower amount

Note

• Actual rates differ after personal deductions
• Use a calculator to compare both methods

Calculate Both Methods

Use our Bonus Tax Calculator — enter bonus + salary, it computes both methods and tells you which is cheaper. Free.