Knowledge base

Practical guides on the Belgian withholding obligation.

nsso·9/22/2026·7 min read

Declaration of works to the NSSO: when, how and why

Anyone having immovable works carried out in Belgium must declare them to the NSSO beforehand. Here is who declares, within what deadline, through which channel and what happens if you forget.

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nsso·9/22/2026·7 min read

Checkinatwork explained: reporting presences on a Belgian site

On larger Belgian sites every presence must be reported to the NSSO each day. Here is when Checkinatwork applies, who reports, how it works and what inspectors find.

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