Signaling Systems: How Belastingdienst Data Flows to Municipalities

Executive Summary

A four-layer system architecture connects Belastingdienst internal systems to municipal debt assistance programs. The FSV (180,000 BSNs registered as “fraudsters”), CAF, and OGS systems generated data that remained siloed within the tax authority until 2024. The Schuldenknooppunt, founded in 2018, became the bridge: the Belastingdienst joined as a creditor in April 2024, then launched an early-warning pilot in June 2025 with 10 municipalities. Municipalities process over 1 million early-warning signals per year through two dominant software platforms.

What Happened

From 2007 to 2024, the Belastingdienst operated internal systems — FSV for fraud signaling, CAF for childcare benefits investigations, OGS for debt qualification — without formal data exchange with municipalities. The FSV registered 180,000 individuals as fraud suspects with labels accessible across all Belastingdienst directorates. The CAF used an 80/20 approach that led to collective benefit stoppages affecting approximately 2,200 families. The OGS qualification blocked debt restructuring (WSNP) for debts above €10,000.

The Schuldenknooppunt was established in 2018 as a standardized data exchange platform between creditors and debt counselors. After a trial period with The Hague and Rotterdam, the Belastingdienst and Dienst Toeslagen officially joined in April 2024 as creditors. In June 2025, a pilot launched for early-warning signals with 10 municipalities: Amsterdam, Arnhem, Apeldoorn, Assen, Den Haag, Hollands Kroon, Leiden, Nijmegen, Tilburg, and Opsterland. Signals are automatically routed to either xxllnc Vroegsignalering (~200 municipalities) or BKR VPS (remaining municipalities).

Evidence

The Divosa Monitor 2025 (158 municipalities) reports that care insurers generate 47% of signals, energy companies 41%, and the Belastingdienst since June 2025. Municipalities process 1 million+ signals annually. 69% use a threshold amount averaging €50. Only 57% of municipalities consider their early-warning approach successful. The Belastingdienst has registered five algorithms in the Algoritmeregister: Dynamic Monitoring (DM), Call After Reminder (BNA), Willen-Can Quadrant (WKK-GG), OB Balance Debts (BAS), and Starting Entrepreneurs (STS) — all linked to collection systems that generate Verplichtingensignalen.

The acronym VPS has two distinct meanings: internally at the Belastingdienst it refers to Verplichtingensignaal (a blocking mechanism for unpaid taxes), while in municipal context it means Vindplaats van Schulden (a debt registry system by BKR). These two systems are now connected through the Schuldenknooppunt data pipeline.

Analysis

The gap between 2013-2024 — when FSV and CAF data was generated but not shared with municipalities — raises critical questions about missed early-warning opportunities for toeslagenaffaire victims. The OGS qualification could flow to municipalities indirectly via WSNP requests, but no formalized pathway existed. The damage chain from FSV registration through risk model activation to collection system enforcement, OGS qualification, and potential WSNP blocking created a reinforcing cycle of harm without municipal safety net awareness. The 2025 pilot represents a structural improvement, but arrives over a decade after the damage began. The transfer of the Schuldenknooppunt to BIDN per 1 January 2026 adds an additional institutional transition to monitor.

Sources

• Xxllnc: xxllnc.nl/applicaties/vroegsignalering/
• Divosa Monitor 2025: divosa.nl/publicaties/
• NVVK (Feb & Jun 2025): nvvk.nl
• Belastingdienst (Apr 2024, 2025): over-ons.belastingdienst.nl
• Schuldenknooppunt: schuldenknooppunt.nl
• BIDN: bidn.nl
• Algoritmeregister: algoritmes.overheid.nl
• MartijnSchut.blog: martijnschut.blog
• RAPPORT-06, RAPPORT-08, RAPPORT-09, RAPPORT-17 (knowledge base)
• WRR Working Paper 021