The issuance of a final assessment (definitieve aanslag)

In the Netherlands, imposing a final income tax assessment will occur when the income tax return filed has been processed. The final assessment in essence closes the year for tax purposes.

Even if no income tax return is filed, the tax office can issue an 'Ex-Officio assessment' (in Dutch: 'ambtshalve aanslag'), which is then based on an estimated amount of taxable income.

The final assessment specifies the amount of tax due (or tax refund), including possible interest and penalties to be included) and it mentions the payment date(s) of the assessment.

If the income is negative, the assessment should be accompanied by a Tax Loss Decree, specifying the amount of the tax loss available for carry forward or carry back.