The 13th-month salary and Tết bonus in Vietnam

Is the 13th-month salary mandatory in Vietnam?

No. A 13th-month salary — in practice a Tết bonus — is not required by Vietnamese law. The Labour Code 2019 leaves bonuses to the employer's own reward policy: Article 104 defines a bonus as money, property or other benefit the employer gives based on business results and how well the employee has done their job, and makes paying one a matter for the employer's published bonus rules rather than a statutory entitlement. It becomes legally binding only once the employer has promised it in a labour contract, a collective bargaining agreement or a published internal bonus policy.1

The custom is strong enough that most employees treat the 13th-month payment as expected rather than optional. It is close to universal across private employers, is usually worth about one month's salary, and is paid in the weeks before Lunar New Year so staff have cash in hand for the holiday. None of that changes the legal position: absent a promise, it is a commercial choice, not a debt. What follows explains how to turn the custom into a predictable, correctly-taxed line in your payroll — and where it sits against the statutory benefits set out in our guide to employee benefits in Vietnam.

When does a 13th-month bonus become binding?

The dividing line is simple: a 13th-month bonus is discretionary until it is written down, and enforceable once it is. Three documents can commit you, and each carries the obligation in a slightly different way.

The practical takeaway for a foreign employer is to be deliberate. If you intend to pay a 13th-month bonus — and in a competitive market you almost always should — set out the formula, the eligibility and the pro-ration rule in writing, so both sides know what is owed and the amount is not argued over each December. If you want to keep genuine discretion, say so explicitly and avoid language that reads as a firm commitment. For the wider contract and policy framework this sits inside, see Vietnam's labour-law and employment-contract basics.

How is the 13th-month salary calculated?

There is no statutory formula, because the payment itself is not statutory. In practice almost everyone uses one of two conventions, and the one you choose should be stated in the bonus policy so it is not disputed:

1. One month's salary, pro-rated

   The most common rule: a full month's salary for a full year of service, reduced in proportion for anyone who joined part-way through the year. The formula is (full months worked in the year ÷ 12) × one month's salary.

2. Average monthly salary of the year

   Where pay changed during the year, some employers base the bonus on the average monthly salary actually earned, which smooths mid-year raises. Either basis is acceptable; the policy just has to say which applies.

A pro-ration example makes the first convention concrete. The table below applies the (months ÷ 12) × one-month rule to an illustrative ₫30,000,000 monthly salary. The figures are illustrative, not a benchmark of what any employer pays.

Is the Tết bonus the same as the 13th-month salary?

In everyday use, yes — most employers and employees use "13th-month salary" (lương tháng 13) and "Tết bonus" (thưởng Tết) to mean the same once-a-year extra month, paid before Lunar New Year. Both are bonuses in the Article 104 sense, and neither is required by law.1 Where people draw a distinction, it is about how the amount is set rather than about the law:

• A 13th-month salary is usually a fixed formula — one month's pay, pro-rated — so the amount is predictable and often written into the contract or policy.
• A Tết bonus is sometimes used for a more discretionary, performance- or results-linked top-up that can vary year to year.

An employer can run one combined payment or both. The timing is what ties them together: both are paid in the run-up to Tết so employees have the money before the holiday. Tết 2027 — the Year of the Goat (Đinh Mùi) — begins on Saturday 6 February 2027, with the official public break running Thursday 4 February to Wednesday 10 February 2027, so the bonus is typically paid in the final January or early-February payroll.5 For the holiday calendar itself, see Vietnam's public holidays; for the paid leave that sits alongside it, see annual leave in Vietnam.

How is a 13th-month salary or Tết bonus taxed?

Two different rules apply, and getting them right is the whole value of a dedicated answer: the bonus is subject to personal income tax, but it is not part of the compulsory social-insurance contribution base.

Personal income tax: yes. A 13th-month salary or Tết bonus is taxable employment income. The Personal Income Tax Law 109/2025/QH15 (Article 3) defines taxable employment income as salaries, wages and amounts of a similar nature, together with other benefits in any form — which covers a bonus. The only bonuses exempt from tax are narrow, State-recognised categories: bonuses attached to State emulation or honour titles, national and international prizes recognised by the State, recognised technical-improvement and invention awards, and rewards for reporting breaches of the law. A commercial year-end or Tết bonus is none of these, so it is fully taxable. The detail now sits in the 2026 implementing rules, Decree 253/2026/ND-CP and Circular 87/2026/TT-BTC, which replaced the former Circular 111/2013/TT-BTC from 1 July 2026.3 The bonus is added to the employee's other taxable income in the month it is paid and taxed on Vietnam's 2026 five-band resident scale (5% to 35%), after the ₫15,500,000 personal deduction and any dependant deductions.4 Because the bonus lands in a single month, it can push that month's income into a higher band than usual; the annual tax finalisation then reconciles the year.

The employer withholds the tax when the bonus is paid, but from 1 July 2026 it declares that withholding to the tax authority quarterly rather than monthly — due 30 April, 31 July, 31 October and 31 January — with an annual finalisation that settles the year.6 The mechanics are set out in our Vietnam personal income tax guide.

Social, health and unemployment insurance: no. The 13th-month bonus does not enter the compulsory social-insurance contribution base. Under the Social Insurance Law 41/2024/QH15, Article 31, the salary on which contributions are charged is the monthly salary — the job or position salary, salary allowances, and only those other additions agreed to be paid regularly and stably in each pay period.2 A bonus under Article 104 of the Labour Code is variable, not a regular, stable monthly amount, so it falls outside that base: no social, health or unemployment insurance is charged on it. The 2% trade-union fee is levied on the same social-insurance salary fund, so it does not reach the bonus either.127 For the full 23.5% employer on-cost that does apply to regular salary — about 21.5% in social, health and unemployment insurance plus the 2% trade-union fee — see Vietnam payroll and employer costs.7

How do you budget the 13th-month bonus into total employment cost?

Budget the 13th-month bonus as one extra month of gross salary a year — roughly an 8.3% uplift on annual base pay if you pay a full month (one month out of twelve). The useful nuance for cost planning is that, because the bonus sits outside the contribution base, it attracts no employer social-insurance, health-insurance, unemployment-insurance or trade-union cost on top: the only deduction is the employee's own personal income tax. So an extra month of salary adds an extra month of gross to your cost, not an extra month of the fully-loaded ~23.5% figure.

The worked example below puts numbers on that for an illustrative Vietnamese employee on ₫30,000,000 a month who is paid a full one-month 13th-month bonus. It compares what the employer pays on a normal month with what it pays in the bonus month.

Across a full year, that employee's regular on-costs run on twelve months of salary while the 13th-month bonus adds one clean month of gross. To model your own numbers — salary, region, nationality and whether you pay a bonus — use the EOR Vietnam cost calculator, which itemises the statutory lines and the flat service fee.

How does EOR Vietnam administer 13th-month pay for you?

When EOR Vietnam is the legal employer, the 13th-month bonus is run through compliant Vietnamese payroll to whatever policy you set. We write the bonus rule into the labour contract or bonus policy so it is clear and enforceable, calculate and pro-rate the amount, withhold the correct personal income tax, show the bonus as a distinct line on the payslip, and pay it on the pre-Tết payroll date you choose. Because the bonus is outside the contribution base, no social-insurance or union cost is added to it — the payslip reflects that automatically.

On price, the bonus does not change our fee. EOR Vietnam charges a flat US$149 per employee per month for a Vietnamese national — the same fee whatever the salary, and whether or not a 13th-month bonus is paid — with no setup, onboarding, offboarding, contract or payslip fees and no hidden fees (as of October 2026). The bonus itself, the regular salary and the statutory employer contributions are passed through to you at cost. Foreign nationals who need a Vietnamese work permit are quoted separately. A refundable security deposit equal to two months of the employee's employment cost (gross salary plus statutory employer contributions) is held for the engagement and returned at the end, less any unpaid amounts. To see where the bonus sits against the rest of a leaver's final pay, see terminating employees in Vietnam, browse all our Vietnam employer guides, or contact us to scope a hire.