Signal Costumers

Stichting Inlichtingenbureau

Is a house shared by several adults? Then the assistance benefit may change. This is because housing costs can then be shared. But not all housemates count towards the benefit. Bureau InformatieDiensten Nederland (BIDN) uses an algorithm to determine this and lets municipalities know if anything changes in the household.

Last change on 17th of July 2025, at 9:10 (CET) | Publication Standard 1.0

• Publication category: Impactful algorithms
• Impact assessment: DPIA
• Status: In use

General information

Theme

Social Security

Begin date

Field not filled in.

Contact information

https://www.bidn.nl/over-ons

Link to publication website

https://www.bidn.nl/rechtmatigheid-samenloopsignalering

Responsible use

Goal and impact

The 'signal cost-sharing' algorithm indicates that something has changed that could affect the level of assistance benefit. This is about who lives in the home of the person receiving assistance. If someone in the house meets certain characteristics (such as age and studies), there may be housing costs (such as rent/mortgage or energy etc.) to be shared. This affects the amount of the benefit. The information on who lives in the household comes from the Rijksdienst voor Identiteitsgegevens (RvIG), and study information comes from the Dienst Uitvoering Onderwijs (DUO).

The purpose of this service is to give municipalities insight into changes at the address of people on welfare benefits or supplementary incomplete old-age pension (AOW) benefits. This is important because these changes can affect the cost-sharing standard and thus the amount of the benefit.

Bureau InformatieDiensten Nederland (BIDN) passes on information about these changes to municipalities. This allows municipalities to better determine whether there is a cost-sharing or joint household. This allows them, if necessary, to adjust the benefit in time to the new situation. It also allows municipalities to check whether the person on benefits has reported the change in address to the municipality, or whether this is new information.

Considerations

The 'signal cost commuters' is part of the information service 'Samenloopsignalering'. See also algorithm 'Samenloopsignalering'. Only the specific points about 'signal commuters' are explained here.

The algorithm ensures that municipalities only receive data on their own residents with social security benefits and where a change has occurred that may affect the cost sharing standard.

This protects citizens' privacy. An advantage of this algorithm is that it works much faster than when someone does it by hand. This saves a lot of time for municipal employees. Also, fewer mistakes are made this way.

Human intervention

With BIDN itself, this algorithm does not involve human intervention. The algorithm executes rules devised by humans and is not 'self-learning'.

However, BIDN does ensure that the processing process has been done properly.

The municipality decides whether and how to deal with a change.

Risk management

Citizen privacy is a major concern. That is why we periodically check whether there are risks and what can be done about them. This is called privacy impact assessment (PIA).

Legal basis

Checking the application of the cost-sharing standard during the social assistance benefit is part of the Regularity Check on the social assistance. The processing of personal data within the framework of the information service 'Regularity Check' has the following basis(s):

Basis of processing RvIG

- Sections 3.1 and 3.2 of the Persons (Basic Registration) Act

- 651001 Authorisation decision of the Intelligence Bureau for municipalities and municipal partnerships

- 651002 Authorisation decision of the Intelligence Bureau

Basis for processing DUO (as a service falling under via the Minister of OCW):

- Sections 64(1)(i) and 68 of the Participation Act

- Section 45(1)(i) Income Support for Older and Partially Incapacitated Former Self-Employed Persons Act (IOAW)

- Section 45(1)(i) Income Support for Older Workers Act (IOAZ).

Basis of processing RINIS:

- DUO-RINIS processing agreement

- IB-RINIS processing agreement

Basis for processing BIDN:

- Article 64, third paragraph, and Article 68 Participation Act

- article 45, second paragraph, IOAW

- Article 45(2), IOAZ

- Section 63 of the Work and Income Implementation Organisation Act (SUWI), Section 5.24(1) and (3) of the SUWI Decree & Sections 6.2 and 6.6 of the SUWI Regulation

- IB-DUO cooperation and exchange agreement

Basis of processing Municipalities:

- Article 19a. (Cost-sharing co-resident) and Article 22a. (Cost-sharing standard) Participation Act

- Chapter 5 'Implementation' and Chapter 6 'Powers and facilities of municipalities' Participation Act

See also the Data Register BIDN. Processing Activities Act SUWI / Participation Act on the BIDN website to be found via the following page: https://www.bidn.nl/privacy-beleid

Links to legal bases

Participatiewet: https://wetten.overheid.nl

Link to Processing Index

https://www.bidn.nl/privacy-beleid

Impact assessment

Data Protection Impact Assessment (DPIA): https://www.bidn.nl/privacy-beleid

Operations

Data

The municipality's benefit file (A):

For this, see the Algorithm "Compounding General".

The demand file to RVIG (B1):

- BSN

The response file to RVIG (B2):

Based on the BSN of the benefit recipient, RVIG provides so-called personal lists of all residents registered with letter or residential address at the same address. In addition to personal data of the residents themselves, these lists also contain some data (BSN, date of marriage and dissolution) of their blood relatives and relatives-in-law, being partner(s), child(ren) and parent(s). These data are processed to infer the relationship (blood or affinity) of the resident to the welfare recipient.

- BSN of benefit recipient (see also the other fields below)

- Category 1 (benefit recipient):

- BSN

- Sex name prefix

- Sex name

- Date of birth

- Category 2 (parent 1):

- BSN

- Category 3 (parent 2):

- BSN

- Category 5 (marriage/registered partnership):

- BSN

- Date of conclusion

- Date of dissolution

- Category 8(residence):

- Date of registration

- Function address

- Date of commencement of address

- Street name

- House number

- House letter

- House number suffix

- House number suffix

- Postal code

- Town name

- Location description

- Category 9 (Child):

- BSN

The demand file to DUO (C1) :

- BSN

The response file to DUO (C2):

- BSN known to DUO (Y/N)

- Education code

- Institution source number

- Enrolment sequence number

- Enrolment date

- Date of deregistration (date BRON minus 1 day)

The signal report to municipality (D) :

- BSN

- Starting date cost sharing

- Signal status (L= Ongoing, E= Ended)

- GBA address/postal code/house number

- Reason for signal

Description of the mutation observed, which is the reason for issuing a signal to the municipality. A maximum of 1 reason is given per signal (previously there could be more).

The possibilities are:

- New registration address occupancy

- End of registration for address residence

- 27th birthday of non-student housemate

- 40th birthday of student co-resident

- Start of education

- Stopped training

If found, the following relationships to client can be listed for new and end of address residence:

- parent

- child

- partner (date from and date to)

- second-degree relationship

- joint child

- Number of non-student co-residents at address over 21 (including applicant)

Technical design

A. A municipality delivers a file relating to the current social assistance population to BIDN monthly via the secure client portal. After each delivery, a processing report is published with an overview of any errors in the delivery;

B.

B1: Each month, BIDN requests a fixed set of data on persons registered at the address of social assistance recipients aged 21 years and older via a message link. This is done for all current benefits.

B2: RvIG returns a response message immediately after receiving a query message with data on persons who are currently registered at the same address as the persons supplied under B1. In addition to the BSN, these so-called 'person lists' contain other data (see Data).

C.

C1: After receiving the residents under B2, BIDN sends a monthly demand file via RINIS (Routerings Instituut (inter)Nationale Informatiestromen) to DUO regarding the BSNs of co-residents aged between 27 and 39 for the purpose of student determination.

C2: DUO sends a monthly response file via RINIS to BIDN with data on current and/or up to 1 year back in time completed enrolment studies of the persons questioned under C1.

D. BIDN sends a monthly response file to the municipality with signals about changes in the situation at the address of benefit recipient(s) that may be relevant to the cost-sharing standard, and thus the level of benefit.

External provider

Internally developed