CIAO check: do you have to check in and out on your site?
Three questions, thirty seconds. You see right away whether your construction site falls under Checkinatwork and whether you have to switch to check-in and check-out.
Last updated:
Your result
No registration duty
Based on your answers, this work does not fall under Checkinatwork.
No registration duty for this site
The duty only applies from a total amount of 500,000 euros (excluding VAT). If the site grows above that amount, you do have to register.
Register daily in Checkinatwork
Register every day, before work starts, who is present on the site: your own employees and your (self-employed) subcontractors. You can do that in Checkinatwork or with an app that submits the registration.
You are not sure of the amount: we assume the duty applies. Ask the client for the total amount of the site.
Check-in and check-out (CIAO)
From 1 April 2027 you register presence on arrival and on departure. For works on immovable property that is no longer possible in Checkinatwork itself, so you need an app or system that supports check-in and check-out.
You are not sure of the amount: we assume the duty applies. Ask the client for the total amount of the site.
Apps that are already ready for check-in and check-out (according to their own site):
This is a simplification of the official NSSO information (checked on October 19, 2026), not legal advice. Your answers stay in your browser.
How does the check work?
You answer three questions about one construction site: the type of work, the total amount and the planning.
The check follows the official information of the NSSO (RSZ/ONSS). The amount counts per site, not per company.
What is CIAO?
CIAO stands for check-in and check-out at work. For works on immovable property, from 1 April 2027 you register attendance on arrival and on departure.
That is laid down in the programme law of 30 May 2026 (title 6, chapter 1, art. 124 to 131). From that date this can no longer be done in Checkinatwork for those works.
What do you do after the check?
Does your site fall under the obligation? Then it is best to choose an app now that supports check-in and check-out.
- Compare: all Checkinatwork apps with score and price.
- Read: who registers, when and how.
Frequently asked questions
Does the check apply to subcontractors?
Yes. Contractors register their own employees and their subcontractors. Employees and self-employed subcontractors can also register themselves.
Are my answers stored?
No. The check runs in your browser and sends nothing.
Is this legal advice?
No. It is a simplification of the NSSO information. In case of doubt, the text on socialsecurity.be prevails.