Tet Bonus & 13th-Month Salary Tax Calculator (VND)
A Tet bonus or 13th-month salary is one of the perks of working in Vietnam — but the figure your employer quotes is gross, and personal income tax (PIT) takes a bite before it reaches your account. The detail that catches people out is how it is taxed: a one-off bonus is added to the taxable income of the single month it is paid in, then run through Vietnam's progressive PIT brackets. Your ordinary monthly salary may sit in a low band, but stacking a large bonus on top pushes the extra income into a higher bracket — so the bonus is effectively taxed at a steeper rate than your usual payslip.
Take a realistic expat case: a 30.000.000 VND monthly salary with no dependents, plus a 60.000.000 VND year-end bonus. In a month without the bonus, taxable income is 11.650.000 VND and PIT is just 665.000 VND. Add the 60.000.000 VND bonus and the month's taxable income jumps to 71.650.000 VND, with the top slice reaching the 30% bracket. The PIT created purely by the bonus is 11.330.000 VND, leaving 48.670.000 VND net — an effective tax rate on the bonus of about 18.88%, far above the tax on a normal month.
The calculator above takes your monthly salary, the bonus amount and your number of dependents, then separates the month's tax with and without the bonus; the difference is the tax on the bonus, and what is left is your take-home. One legal caveat: the boundaries between the 20% and 30% brackets in the 2026 law are still pending the implementing decree, so if your bonus reaches that band, treat the figure as an estimate until the rules are confirmed.
How a Tet bonus or 13th-month salary is taxed
The rule: a bonus is added to the month it is paid
In Vietnam, a Tet bonus and 13th-month salary are taxable employment income. They are not taxed separately at a flat rate — they are lumped into the taxable income of the month they are received and run through the progressive PIT schedule. Because the schedule is progressive, each additional dong of income is taxed at the rate of the bracket it falls into, which is why a large bonus usually carries a higher effective rate than a regular salary.
How the tool isolates the tax on the bonus alone:
- Compute the month's PIT without the bonus (salary only).
- Compute the month's PIT with the bonus added to taxable income.
- Tax on the bonus = (2) − (1) — the marginal cost of the bonus.
- Net bonus = Bonus − Tax on the bonus; effective rate = Tax on the bonus ÷ Bonus.
Compulsory insurance is not charged on the bonus
Important for the maths: compulsory insurance (BHXH 8%, BHYT 1.5%) is levied on your contractual salary, not on a one-off bonus — and as a foreign employee you do not pay BHTN (unemployment insurance) at all. Because the insurance amount is the same whether or not the bonus is paid, it cancels out when we take the difference between the two months, so the extra tax comes entirely from the bonus inflating taxable income.
2026 family deductions and the bracket table
Monthly taxable income = Salary + Bonus − Compulsory insurance − Personal deduction (15.500.000 VND) − Dependent deduction (6.200.000 VND each), under PIT Law No. 109/2025/QH15 and Resolution 110/2025/UBTVQH15. The five-bracket schedule:
| Bracket | Monthly taxable income (VND) | Rate |
|---|---|---|
| 1 | Up to 10.000.000 | 5% |
| 2 | 10.000.000 – 30.000.000 (*pending implementing decree) | 10% |
| 3 | 30.000.000 – 60.000.000 (*pending implementing decree) | 20% |
| 4 | 60.000.000 – 100.000.000 (*pending implementing decree) | 30% |
| 5 | Over 100.000.000 | 35% |
The 5% bracket (up to 10M) and the 35% bracket (over 100M) are stated in the law; the 20%-to-30% boundaries are still awaiting the implementing decree (marked * above). If your bonus pushes taxable income into that range, the result is an estimate rather than a settled figure.
What the model leaves out
The tool assumes the entire bonus is paid in one month, which matches a typical single Tet payout. In practice your employer may withhold differently and you reconcile at the annual tax finalisation, where the final tax is computed on your full-year income and can differ from this monthly estimate. It also ignores other tax-exempt allowances and assumes you are a tax resident; non-residents are taxed on Vietnam-sourced employment income at a flat 20%, which this monthly-bracket model does not apply.
Worked example: 30.000.000 VND salary, 60.000.000 VND bonus, 0 dependents
Assumptions: a tax resident, insurance paid on the full 30.000.000 VND salary (below the cap), foreign employee so no BHTN, 0 dependents, the whole bonus paid in a single month.
| Item | Month without bonus | Month with bonus |
|---|---|---|
| Income (salary + bonus) | 30.000.000 | 90.000.000 |
| Less compulsory insurance (9.5%) | −2.850.000 | −2.850.000 |
| Less family deductions | −15.500.000 | −15.500.000 |
| Taxable income | 11.650.000 | 71.650.000 |
| PIT for the month | 665.000 | 11.995.000 |
The difference between the two tax columns — 11.995.000 − 665.000 = 11.330.000 VND — is the tax caused by the bonus. After it, you keep 48.670.000 VND of the 60.000.000 VND bonus, an effective rate of 18.88%.
The point is the bracket creep: without the bonus the month attracts only 665.000 VND of tax, but the 60.000.000 VND bonus lifts the top slice into the 30% band, so the bonus bears an effective 18.88% — several times the rate on a normal month. Because this example reaches into the 30% range whose boundary is still pending the implementing decree, read it as a close estimate rather than a confirmed number. To see the full-year picture, pair this with FiMo's gross-to-net salary calculator.
Frequently asked questions
Is a Tet bonus taxable in Vietnam?
Yes. A Tet bonus and 13th-month salary are taxable employment income, added to the taxable income of the month they are paid and run through the progressive PIT brackets. Example: a 30.000.000 VND salary with a 60.000.000 VND bonus and 0 dependents generates 11.330.000 VND of extra PIT, leaving 48.670.000 VND net. The bonus is only tax-free if the month's total taxable income remains zero after deductions, which is rare for a sizeable bonus.
How is the tax on a year-end bonus calculated?
The bonus is added to the income of the month it is received, not taxed at a separate flat rate. To isolate the tax on the bonus alone, compute the month's PIT with the bonus and subtract the PIT the month would have had without it. In the example: 11.995.000 VND with the bonus minus 665.000 VND without it = 11.330.000 VND tax on the bonus. Because the brackets are progressive, a large bonus tends to land in a higher band than your regular salary.
Why is my bonus taxed at a higher rate than my salary?
Because Vietnam's PIT is progressive: higher income means the top slice is taxed at a higher rate. Your monthly salary may sit in a low bracket, but adding the bonus pushes the extra income into a higher one. In the example, an ordinary month is taxed almost entirely at the lowest band, but the 60.000.000 VND bonus lifts the top slice to the 30% bracket, producing an effective rate of about 18.88% on the bonus — well above the rate on a normal payslip.
Do foreign employees pay insurance on a Vietnam bonus?
Compulsory insurance (BHXH 8%, BHYT 1.5%) is charged on your contractual salary, not on a one-off bonus, and foreign employees do not pay BHTN (unemployment insurance) at all. Because the insurance amount is identical whether or not the bonus is paid, it cancels out when isolating the tax on the bonus — the extra tax comes purely from the bonus increasing taxable income. Confirm your specific insurance base with HR, as some fixed salary-like allowances can be included.
Are the 2026 bracket figures final?
The 5% bracket (up to 10M VND/month) and the 35% bracket (over 100M) are confirmed by PIT Law 109/2025/QH15, and the 2026 family deductions (15.500.000 VND for yourself, 6.200.000 VND per dependent) are set by Resolution 110/2025/UBTVQH15. However, the boundaries between the 20% and 30% brackets are still awaiting the implementing decree. If your bonus reaches that range — as the worked example does at the 30% band — treat the output as a close estimate until the decree is published.
Will the monthly estimate match my final tax bill?
Not exactly. This is a monthly estimate that mirrors how a one-off bonus is typically withheld. Your final liability is settled at the annual tax finalisation, which is computed on your full-year income across all twelve months and can differ from a single-month calculation. The model also assumes you are a tax resident; non-residents are taxed on Vietnam-sourced employment income at a flat 20%. Use this to budget your take-home, and reconcile at year-end finalisation.