Practical solutions for CIAW compliance, visibility, and control when managing subcontractors on Belgian construction sites
On any given Belgian construction site, 40-70% of the workforce are subcontractors. They arrive from different companies, speak different languages, and follow different schedules. Yet as a main contractor, you are legally responsible for every single one of them being correctly registered. A missing CIAW registration doesn’t just mean a fine for the subcontractor, it means a fine for you.
This article explains exactly how subcontractor time registration works on Belgian construction sites, what your legal obligations are, and how digital tools make compliance practical rather than painful.
Quick Navigation
- The Subcontractor Challenge: Why It’s So Hard
- Your Legal Obligations as Main Contractor
- How Digital Time Registration Works for Subcontractors
- Registration Methods: What Works Best
- Real-World Scenario: Before and After
- Frequently Asked Questions
The Subcontractor Challenge: Why It’s So Hard
Managing time registration for your own employees is one thing. You control their devices, their training, and their processes. Subcontractors are a different story entirely:
❌ They use their own systems (or no system at all)
❌ They may arrive at different times than scheduled
❌ They often don’t have company smartphones
❌ Language barriers make instructions difficult
❌ Subcontractor chains (sub-sub-contractors) add layers of complexity
❌ Worker turnover is high, new faces appear weekly
The result? Main contractors often discover compliance gaps only when it’s too late, during an NSSO inspection or after an accident when the evacuation list doesn’t match who’s actually on site.
Your Legal Obligations as Main Contractor
⚠️ Critical: Under Belgian law, chain liability means the main contractor bears responsibility for subcontractors’ compliance. This includes CIAW (Check In at Work) registrations. If your subcontractor fails to register their workers, YOU face the consequences.
| Obligation | Requirement | Penalty for Non-Compliance |
| CIAW registration | Every worker must be registered before starting work on site | Up to €6,000 per worker per day |
| CIAW thresholds | No subcontractor: > €500K | 1 subcontractor: > €5K | 2+ subcontractors: always | Same fine structure applies |
| Chain liability | Main contractor responsible for entire chain | Fines, project suspension, blacklisting |
| 2027 time recording mandate | All employers must have objective time recording system | NSSO enforcement, fines pending |
| Safety attendance | Know who is on site at all times for evacuation | Criminal liability in case of accident |
The upcoming CIAO expansion (Check In AND Out) will add exit registration requirements, making real-time presence tracking even more critical. For the cleaning sector, this is already active since 2025. Construction is expected to follow.
Full CIAW FAQ and threshold details →
How Digital Time Registration Works for Subcontractors
The key insight is that subcontractor registration doesn’t require the subcontractor to have the same system as you. A well-designed platform gives you multiple ways to register workers, regardless of which company employs them:
Option 1: Site-Based Registration (Recommended)
Install registration hardware at site entry points, badge readers, site poles, or QR code stations. Every worker, regardless of employer, registers by scanning their badge, phone, or ID when they enter and leave. This is the most reliable method because it doesn’t depend on the subcontractor’s cooperation or technology.
Option 2: Mobile App Registration
Subcontractors download the app and register via their own smartphone. This works well for subcontractors who are tech-savvy and have company phones, but requires onboarding each subcontractor company. GPS verification ensures registrations happen on-site.
Option 3: Main Contractor Registers on Behalf
For subcontractors without smartphones or badges, the site manager can register workers manually through the platform’s admin interface. This is a fallback option but ensures no one falls through the cracks.
Option 4: Hybrid Approach
Most large sites use a combination: site poles at the main gate for everyone, app registration for regular subcontractors, and manual registration for occasional workers. The platform consolidates all registrations into a single view.
Registration Methods: What Works Best
| Method | Subcontractor Effort | Main Contractor Control | Best For |
| Site pole / badge reader | Minimal (scan and go) | Full control | Large sites, 50+ workers |
| QR code at gate | Low (scan with phone) | Good control | Medium sites, mixed workforce |
| Mobile app | Medium (download + register) | Moderate | Regular subcontractors |
| Manual registration | None (done by site manager) | Full control | Occasional workers, no tech |
✅ Pro tip: The best approach is to make registration as frictionless as possible for subcontractors. The less effort required, the higher the compliance rate. Site poles and badge readers consistently achieve 98%+ registration rates because workers simply walk past them.
Real-World Scenario: Before and After
The situation: A Belgian construction company manages 8 active sites with 120 own employees and 200+ subcontractor workers. Before digital registration, the site manager kept a paper sign-in sheet at the site office. Subcontractors often forgot to sign in, arrived before the office opened, or left without signing out.
| Aspect | Before (Paper) | After (Digital) |
| Daily registration compliance | 60-70% | 97-99% |
| Time to generate CIAW report | 2-3 hours per site per week | Automatic, real-time |
| Evacuation list accuracy | Unreliable (paper at office) | Real-time on any device |
| NSSO inspection readiness | Stressful, incomplete records | Instant export, full audit trail |
| Admin time per site per week | 4-6 hours | 30 minutes (exceptions only) |
| Subcontractor disputes | Weekly | Monthly at most |
“The biggest win wasn’t even compliance, it was knowing exactly who is on our site at any moment. When we had a safety incident last year, we could account for every person within minutes instead of running around with a clipboard.”
– Site Manager, Belgian main contractor (8 sites)
Frequently Asked Questions
Do subcontractors need to install an app?
Not necessarily. If your site uses badge readers or site poles, subcontractors simply scan at the gate, no app needed. The app is an option for subcontractors who prefer mobile registration. The goal is to offer multiple methods so every worker can register, regardless of their technical setup.
What if a subcontractor refuses to register?
Under Belgian law, you have the right and obligation to require registration. Include digital time registration requirements in your subcontractor agreements. In practice, most resistance disappears when the registration method is simple (e.g., badge scan at the gate). If a subcontractor consistently fails to comply, you can escalate through contractual penalties.
How do we handle sub-sub-contractors (chain subcontracting)?
The registration system doesn’t distinguish between subcontractor levels, every worker on site registers the same way. The CIAW system captures the employer’s company number (KBO/BCE), so the chain of responsibility is documented automatically. As main contractor, ensure all levels of your chain are informed of the registration requirement.
Can we see real-time who is on site right now?
Yes. With check-in and check-out registration (via site poles, app, or badges), the platform provides a real-time presence dashboard showing every person currently on site, their employer, and their check-in time. This is invaluable for safety, evacuation planning, and daily management.
What about GDPR when registering subcontractors’ workers?
You have a legal basis for processing this data under Belgian employment and safety regulations. The data collected is limited to what’s legally required: name, employer, NSSO number, and presence times. Inform subcontractors in your agreements that their workers will be registered, and ensure your data processing meets GDPR standards.
Suivo Check-in at Work Solution →
Construction Industry Solutions →
Time Registration for Construction: The Complete Guide →
Full Visibility Over Every Worker on Your Site
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