Please note: The algorithm descriptions in English have been automatically translated. Errors may have been introduced in this process. For the original descriptions, go to the Dutch version of the Algorithm Register.

Premium differentiation Unemployment Act (PDWW)

This page contains information about the algorithm 'Premium differentiation Unemployment Act'. This algorithm checks whether employers have correctly applied a revision of the General Unemployment Fund premium.

Last change on 30th of October 2025, at 15:46 (CET) | Publication Standard 1.0
Publication category
Impactful algorithms
Impact assessment
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Status
In use

General information

Theme

Public finance

Begin date

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Contact information

algoritmeregister@belastingdienst.nl

Link to publication website

https://over-ons.belastingdienst.nl/onderwerpen/omgaan-met-gegevens/algoritmeregister/

Link to source registration

https://over-ons.belastingdienst.nl/onderwerpen/omgaan-met-gegevens/algoritmeregister/premiedifferentiatie-werkloosheidswet-pdww/

Responsible use

Goal and impact

The Tax Authority checks withholding agents for correct and complete declaration and payment of payroll taxes. Payroll taxes consist of wage tax, national insurance contributions, employee insurance contributions and the income-related Healthcare Insurance Act contribution. Withholding agents (such as an employer, pension fund or benefits agency) withhold wage tax and national insurance contributions from their employee's wages and, in some cases, the income-related Healthcare Insurance Act contribution. They remit this to the Tax Office. The employee insurance contributions and usually the income-dependent Healthcare Insurance Act contribution are not deducted from the employee's wage, but are paid by the employer to the Tax Administration.

The premium for the General Unemployment Fund (AWf) has a differentiation according to the nature of the employment contract. By this we mean that premium depends on the employment contract. The employer pays the low AWf premium for a written permanent employment contract that is not an on-call contract. For most other employment contracts, the employer pays the high premium AWf.

If the employer was right to apply the low AWf premium, he must still pay the high AWf premium retroactively in two cases:

  1. The employment contract ends no later than 2 months after commencement.
  2. The employee has more than 30% extra paid hours in a calendar year, over and above the hours agreed in the employment contract.

The purpose of the algorithm is to check whether employers have revised correctly.

Considerations

The Premium Differentiation Unemployment Act algorithm is important for correct remittance of the AWf premium. We want to do this carefully. The algorithm can support an employee of the Tax Administration in this. As a result, the assessment is more careful, efficient and uniform.

Human intervention

Human intervention in the Tax Administration context implies that a competent and knowledgeable employee plays a substantial role in decision-making.

The operation of the algorithm always involves human intervention. The algorithm detects and selects. It is the Tax Administration employee who makes the decision.

Risk management

The General Administrative Law Act (Awb) requires the government's actions to be transparent and lawful. The Tax Administration observes the general principles of good governance when applying and developing algorithms.

The algorithm uses data collected under various tax laws. As required by the AVG, no more data is used than necessary.

The selection rules are reviewed periodically and adjusted if necessary to remain compliant with laws and regulations.

Legal basis

  1. General Administrative Law Act:
  2. General Data Protection Regulation:
  3. Archives Act 1995:
  4. General Administrative Law Act:
  5. General State Tax Act:
  6. General Data Protection Regulation Implementation Act
  7. Labour Market in Balance Act
  8. Social Insurance (Funding) Act

Links to legal bases

  • General Administrative Law Act:: https://wetten.overheid.nl/BWBR0005537/
  • General Data Protection Regulation:: https://eur-lex.europa.eu/legal-content/NL/TXT/HTML/?uri=CELEX:32016R0679
  • Archives Act 1995:: https://wetten.overheid.nl/BWBR0007376/
  • General Administrative Law Act:: https://wetten.overheid.nl/BWBR0005537/
  • General State Tax Act:: https://wetten.overheid.nl/BWBR0002320/
  • General Data Protection Regulation Implementation Act: https://wetten.overheid.nl/BWBR0040940/
  • Labour Market in Balance Act: https://wetten.overheid.nl/BWBR0042307/
  • Social Insurance (Funding) Act: https://wetten.overheid.nl/BWBR0017745/

Elaboration on impact assessments

  • Privacy and AVG

The use of data is tested against the General Data Protection Regulation (AVG). Reviewing personal data reveals any privacy risks and allows appropriate measures to be taken.

The AVG prescribes that no more data should be used than necessary. This is called data minimisation. The Tax Administration regularly examines whether the data used are still necessary and may therefore be used.


  • Use of special personal data

This algorithm does not use special personal data.


  • Equality and non-discrimination

The algorithm is assessed in line with applicable non-discrimination principles for direct and indirect discrimination. Processing as little personal data as possible reduces the risk of direct discrimination. Employees involved in developing and managing the algorithms receive training on data protection and bias.

Operations

Data

  1. Identifying data (BSN, date of birth)
  2. AWf data
  3. Employment-related data
  4. Contractual data

Links to data sources

  • Identifying data (BSN, date of birth): Belastingdienst/UWV
  • AWf data: Belastingdienst/UWV
  • Labour-related data: Belastingdienst/UWV
  • Contractual data: Belastingdienst/UWV

Technical design

The algorithm consists of selection rules drawn up by content experts based on laws, regulations and expertise.

If the revision has not been applied (correctly), the withholding agent is notified. If necessary, a correction obligation can be imposed.

The algorithm is not self-learning. This means that the algorithm does not develop itself during its use.

External provider

The algorithm was developed by UWV and Tax Administration staff and is also maintained internally.

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