Letters from Belastingdienst
Aanslag 202..
Inkomstenbelasting
Premie volksverzekeringen
Action: check if the amounts line up with your income tax return 2023
The document "Aanslag 20.." is your final income tax assessment. If the final assessment is in accordance with the information in your tax return you can agree with the assessment, which means that the tax year is closed.
Te betalen = payable result
Te betalen nihil = nil result
Te ontvangen = refundable result
In case of a payable result, you need to arrange for payment within 8 weeks from assessment date. If you fail to pay timely, you will receive a "Herinnering" (reminder).
Tax assessment based on estimation
In case you failed to file a tax return (timely) it is possible that the Dutch tax authorities issue an assessment on the basis of an estimation of your income. Usually the result is a rather large payable result. In order to object, you can file an income tax return. The Dutch tax authorities will charge you with a penalty in this situation.
Objection
If the assessment is not in accordance and you do not agree with the tax assessment, you can object within 6 weeks from the date on the tax assessment. In case of objection, the Dutch tax authorities are required to look into your objection. If you miss out on the 6 week deadline, you can still request for a reduction - but the Dutch tax authorities no longer have an obligation to look into the matter.

