What is Thirteenth Month?
Thirteenth month pay, known in Dutch as the dertiende maand, is an additional salary payment equal to approximately one month's gross wage, paid once per year on top of twelve regular monthly salaries and the statutory 8% vakantiegeld. It is a contractual benefit, not a statutory right, and exists in the Netherlands only where an employment contract or an applicable collective labour agreement (CAO) expressly provides for it.
Employers using Octagon's Employer of Record services budget for thirteenth month pay at the offer stage, because once written into the contract it becomes a binding part of the total compensation package and cannot be removed unilaterally.
How does Thirteenth Month work?
When a thirteenth month is granted, it accrues at 8.33% of gross monthly salary across the calendar year and is paid as a lump sum, most often with the December payslip. Some CAOs split the payment between June and December, and others structure it as an eindejaarsuitkering tied to company performance or individual metrics. The payment is processed through standard Dutch payroll, appears as a separate line on the payslip, and is subject to loonheffing at the bijzonder tarief, the special rate that applies to all non-recurring lump-sum earnings.
For cost modelling across different benefit structures, see EOR hidden costs and the detailed thirteenth month Netherlands guide.
Who does Thirteenth Month apply to?
Thirteenth month pay applies to employees whose individual contract or governing CAO explicitly includes the benefit. Many sector-wide CAOs, including those covering banking, insurance, energy, and parts of the public sector, contain a thirteenth month or eindejaarsuitkering clause. Multinational employers often introduce it to align Dutch packages with global pay benchmarks and to strengthen retention in competitive roles. Part-time employees accrue pro rata, and new joiners accrue from their start date.
When does Thirteenth Month not apply?
Thirteenth month pay does not apply where the employment contract is silent on the benefit and no CAO imposes it. It does not apply to genuine self-employed contractors, who invoice for services without any employment-linked bonus entitlement, and it cannot be claimed retroactively against an employer who has never offered it. Where a discretionary end-of-year bonus is paid ad hoc rather than as a structured benefit, it falls outside the thirteenth month framework even though the payroll tax treatment under the bijzonder tarief is the same. For expats, the 30% ruling applies to thirteenth month pay only on the taxable portion, as covered in the 2025 30% ruling update.