Belgian sick leave has a reputation for complexity, and it is deserved. The employer’s obligation is called guaranteed salary (gewaarborgd loon / salaire garanti), it is paid at different rates depending on whether the employee is white-collar or blue-collar, and after roughly a month it hands over to the employee’s health insurance fund — the mutuality — on a completely different basis.
This guide covers Belgian sick leave in 2026: who pays what and for how long, the certificate rules including the certificate-free day, the handover to the mutuality, and the return-to-work trajectory that now sits at the centre of long-term absence management.
Key takeaways
- White-collar employees (employés / bedienden) on indefinite contracts receive 100% of salary for the first 30 days of incapacity, paid by the employer.
- Blue-collar employees (ouvriers / arbeiders) receive a tiered guaranteed salary across the same first month, at declining rates with a mutuality contribution.
- Employees may be absent without a medical certificate for one day, up to three times per calendar year — though employers with fewer than 50 staff can opt out.
- After the guaranteed salary period, the mutuality pays incapacity benefit at a percentage of capped earnings, first as primary incapacity (up to one year), then invalidity.
- A statutory return-to-work trajectory applies to long-term absences and must be followed before medical force majeure can end the contract.
Guaranteed salary: white-collar
For a white-collar employee on an indefinite contract (or a fixed-term contract of three months or more), the employer pays full normal salary for the first 30 calendar days of incapacity. There is no waiting day and no reduction across that month.
For contracts shorter than three months, the white-collar employee is treated closer to the blue-collar structure until they have completed one month’s service. Employees still in their first month of service have limited or no guaranteed salary entitlement, and fall back on the mutuality earlier.
Guaranteed salary: blue-collar
Blue-collar guaranteed salary is tiered across the same first month, and the tiers involve both the employer and the mutuality:
| Period of incapacity | Who pays and at what level |
|---|---|
| Days 1–7 | Employer, 100% of normal pay |
| Days 8–14 | Employer, a large majority of normal pay |
| Days 15–30 | Employer pays a supplement on top of mutuality benefit |
| From day 31 | Mutuality only, at the incapacity benefit rate |
The precise percentages in the days 8–30 window are set by royal decree and are adjusted from time to time, so payroll should be configured from the current official figures rather than from a policy document written years ago.
Belgium has been progressively harmonising the white-collar and blue-collar statutes since the 2014 unified status reform, so check the current position for your joint committee (paritair comité / commission paritaire) — sector rules can be more generous than the statutory floor.
Medical certificates and the certificate-free day
Since late 2022, an employee may be absent for a single day without a medical certificate, up to three times in a calendar year. It applies only to the first day of an absence, and the employee must still notify the employer immediately and state where they can be reached.
Employers with fewer than 50 employees can disapply the certificate-free day through a collective labour agreement or a clause in the work rules (arbeidsreglement / règlement de travail). If your work rules are silent, the certificate-free day applies by default.
Outside that allowance, a certificate is required, and the employee must generally send it within two working days unless the work rules or a collective agreement set a different deadline.
The employer’s control doctor
Belgian employers may send a control doctor (controlerend geneesheer / médecin-contrôle) to verify incapacity, at the employer’s cost. The employee must allow the visit. Where the employee is required to stay home for a defined window during the first days of absence, that requirement must be set out in the work rules or a collective agreement.
If the control doctor disagrees with the treating doctor, the dispute goes to an arbitration doctor whose decision binds both parties. An employee who refuses to see the control doctor without valid reason can lose guaranteed salary for the days before the check.
After 30 days: the mutuality
From day 31, the employee’s health insurance fund pays primary incapacity benefit (arbeidsongeschiktheidsuitkering) at a percentage of capped gross earnings. Primary incapacity runs for up to one year; after that the employee moves into invalidity, administered by the national institute for health and disability insurance (RIZIV / INAMI).
Because benefit is calculated on capped earnings, higher earners see a substantial income drop at day 31. Sector agreements and employer group insurance often provide a top-up, but nothing statutory requires one.
Return-to-work trajectories
Long-term absence in Belgium is managed through a structured return-to-work trajectory (re-integratietraject / trajet de réintégration), run through the occupational health service. It can be started by the employee, the employer (after a defined period of absence), or the advising physician of the mutuality.
The occupational health physician assesses whether the employee can return to their own work, adapted work, or other work — or that no return is possible. Since the 2022–2023 reforms, ending a contract for medical force majeure is a separate procedure that can only be started after a minimum period of continuous incapacity and cannot simply be tacked onto a failed reintegration assessment.
Employer obligations
Belgian employers have six core duties:
- Pay guaranteed salary at the correct white-collar or blue-collar structure for the first month.
- Apply the certificate-free day unless it has been properly disapplied in the work rules of a company with fewer than 50 employees.
- Set certificate deadlines and home-presence rules in the work rules, not by informal instruction.
- Report the absence to the mutuality and social secretariat so benefit starts on time at day 31.
- Engage with the return-to-work trajectory and consider adapted or other work in good faith.
- Follow the separate medical force majeure procedure rather than treating a failed reintegration as automatic termination.
Common pitfalls
1. Applying one rate to both employee categories
White-collar and blue-collar guaranteed salary structures differ across the first month. A single flat rule overpays one group and underpays the other.
2. Refusing the certificate-free day
Companies with 50 or more employees cannot disapply it at all, and smaller companies can only do so through the work rules or a collective agreement. Rejecting a valid certificate-free absence is a common and easily challenged error.
3. Requiring house arrest without a legal basis
An obligation to be home for a control visit must be in the work rules or a collective agreement, and must be limited to a defined window. Open-ended informal requirements do not hold up.
4. Assuming the mutuality replaces full salary
Primary incapacity benefit is a percentage of capped earnings. Higher earners drop sharply at day 31, and employers who never explain this face predictable disputes.
5. Mishandling medical force majeure
The procedure is separate from the reintegration trajectory, has its own minimum absence period and steps, and cannot be short-cut. Getting it wrong turns a medical exit into an unfair dismissal claim.
For more context, see our guide to annual leave entitlement in Belgium, the comparison of sick leave across Europe, and the overview of the main types of leave employers manage.
Frequently asked questions
How long does a Belgian employer pay salary during sick leave?
Broadly the first month. White-collar employees on indefinite contracts get 100% of salary for 30 days; blue-collar employees get a tiered guaranteed salary across the same period.
Can an employee be off sick without a doctor’s note in Belgium?
Yes — one day at a time, up to three times per calendar year. Employers with fewer than 50 employees can disapply this through a collective agreement or the work rules.
Who pays after the guaranteed salary period?
The employee’s mutuality, as primary incapacity benefit for up to one year, then invalidity benefit administered through RIZIV / INAMI.
Can an employer check that an employee is genuinely sick?
Yes. The employer may send a control doctor at its own cost. If the control doctor and treating doctor disagree, an arbitration doctor decides, and that decision is binding.
How quickly must a certificate be submitted?
Generally within two working days, unless the work rules or applicable collective agreement set a different deadline.
Can an employer dismiss a long-term sick employee?
Only through the correct route. Medical force majeure is a distinct statutory procedure with a minimum period of continuous incapacity and defined steps, separate from the return-to-work trajectory.
Putting it into practice
Five checks cover most Belgian sick leave risk:
- Confirm each employee’s status and joint committee, and configure guaranteed salary to the right structure.
- Check the work rules actually address the certificate-free day, certificate deadlines, and control visits.
- Track certificate-free days per employee per calendar year so the third one is the last.
- Report absences on time so mutuality benefit starts at day 31 without a gap.
- Start the return-to-work trajectory early on long absences, and document every adapted-work option considered.
A leave management system that separates guaranteed salary rules by employee category, counts certificate-free days against the annual limit, and flags the day-30 handover means Belgium’s layered model runs as configuration rather than as a manual calculation every time someone calls in sick.
Sources
- FPS Employment, Labour and Social Dialogue — incapacity for work (primary source)
- RIZIV / INAMI — incapacity benefit
- Belgian Official Gazette — Employment Contracts Act of 3 July 1978
Last updated: 26 July 2026. This article is general guidance, not legal advice. Guaranteed salary percentages, benefit rates, and earnings caps are revised periodically — confirm current figures with your social secretariat and the applicable joint committee.