Q: Do you know when you are required to report a cyber incident, to whom, and within what timeframes?
Significant incidents must be reported in layers: an early warning within 24 hours, followed by a formal notification within 72 hours and a final report within one month. This regime currently applies under the Network and Information Systems Security Act (Wbni). The Cybersecurity Act (Cbw) anchors these timeframes more explicitly in statute and substantially widens the scope: where the Wbni applied only to individually designated essential service providers, the Cbw applies automatically to all essential and important entities across eighteen designated sectors.
For many organisations, the reporting obligation will be an entirely new requirement (check the Cbw list).
Where a cyber incident also involves personal data, you must report in two places: an early warning to the NCSC within 24 hours under the Wbni (future: Cbw), and a formal data breach notification to the Dutch Data Protection Authority within 72 hours under the GDPR. Both notifications carry their own threshold criteria and their own formats. A joint internal protocol prevents either one from being missed.