Incapacity for work and medical certificates


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As a result of the Covid-19 crisis, various measures have been taken regarding sick pay and incapacity for work benefits.


During the state of crisis, the 26-week period of protection against dismissal in the event of incapacity for work is suspended.

An employee on sick leave (due to sickness or accident) must:

  • inform their employer as from the first day of absence and;
  • provide a medical certificate at the latest on the third day of absence.

Example: a salaried worker on a part-time contract who does not work on Mondays but who is away from work due to illness as from the Monday must inform their employer of their condition as of Tuesday (first day of absence from work) and hand in the medical certificate by Thursday midnight at the latest (third day of absence).

He or she is thereby protected against dismissal.

However, the employer may, in certain cases, request that the employee undergoes:

  • either an administrative check;
  • or a medical check.

Who is concerned

An employee must inform their employer of their incapacity for work due to illness or accident, either verbally or in writing (e-mail, fax or text message) on the first day of absence.

He may do so directly or via a third party.

However, simply telling a work colleague is not sufficient as this information may not be relayed to the employer.

The employee has to provide a medical certificate at the latest on the third day of absence.

How to proceed

Employee obligations

Employees must always inform their employer from the first day of absence.

During sick leave, the employee still has an obligation of loyalty to their employer and they can not carry out any other professional or similar activity during the period of incapacity for work.

Sick leave of 1 or 2 days

If sick leave lasts only 1 or 2 days, the employee may, depending on business practice, be exempt from having to provide a medical certificate for these days.

Nevertheless, an employer may still request that their employee justifies an absence of 1 or 2 days. A (salaried) worker must always be able to justify their absences from work, whatever their duration.

Sick leave of 3 days or more

Before the end of the third day of incapacity for work, the employee (regardless of whether they are a resident or a cross-border worker) must ensure that their employer has received the medical certificate.

Employees must send:

  • the first sheet of the medical certificate, duly completed and signed by their attending physician, to the National Health Fund (Caisse Nationale de Santé - CNS);
  • the second sheet to their employer.

The employee must keep third sheet of the certificate for personal use, where necessary.

From a social security point of view, the medical certificate must be established on the third day of medical leave or of its extension at the the latest. Each medical certificate which has a retroactive validity exceeding 2 days will only be taken into consideration by the CNS as from its date of establishment.

Urgent hospitalisation

In the event of urgent hospitalisation, the employee has 8 days from the date of hospitalisation to send a medical certificate to their employer.

If during this period a dismissal procedure was initiated against the worker, the procedure is deemed to be null and void provided the worker submitted the medical certificate (certificate of incapacity for work) to the employer within 8 days of hospitalisation.

Extension of the period of incapacity for work

If the period of incapacity for work is extended beyond the period initially set, the employee must:

  • inform their employer on the first day on which they were initially expected to return to work;
  • send a medical certificate:
    • to the CNS before the end of the second day after the day where the employee was initially expected to return to work;
      If the last day of this deadline falls on a Saturday, Sunday or public holiday, the deadline is extended to the next working day.
    • to the employer who must be in possession of the extended medical certificate before the end of the third day of extended medical leave.

When an employee returns to work following a uninterrupted absence of more than 6 weeks due to illness or accident, the employer must inform the competent occupational health practitioner in charge of their business. The occupational health practitioner will decide whether the employee must undergo a medical check. He or she will then determine whether the employee is able to return to their workstation or if another position may be more appropriate or if they should be redeployed.

Incapacity for work during annual leave

If the resident or cross-border worker is on sick leave during a leave and if they are in Luxembourg, they must send their employer a medical certificate within 3 working days.

If the resident or cross-border worker is in a foreign country, they must inform their employer as soon as possible.

If the employee is on sick leave while having their annual leave, the days covered by the medical certificate are not deemed to be days of leave. These days of leave may therefore be taken at a later date.

Permission to go out during an incapacity for work period

During the period of incapacity for work, the worker is not allowed to go outside during the first 5 days of sick leave (except to have a meal, under certain conditions) even if the medical practitioner has stated otherwise on the medical certificate.

From the sixth day of sick leave (only if not advised against by the attending physician), the worker is allowed to go outside between 10.00 and 12.00 and between 14.00 and 18.00 (even if this is not indicated on the medical certificate of incapacity for work).

A person on sick leave may not:

  • join in sports activities (unless medically indicated);
  • carry out any activity which is not compatible with their state of health;
  • go to a drinking or eating establishment, except to have a meal (as from the first day of incapacity for work) and provided the person has previously informed the National Health Fund (CNS) by using the specific form, or by phone, fax or email.

The person on sick leave must provide the relevant health fund with their name and first name, and the exact address (place, street, number, floor, etc.) where he or she will be staying during the period of incapacity for work. If said address is different from the home address, it must be indicated on the medical certificate of incapacity for work, or failing this, be communicated to the CNS via phone, fax or email. Similarly, persons on sick leave staying with a third party have to indicate the name and first name of said third party including the duration of their stay.

Essential visits for a medical check at the social security (Contrôle médical de la sécurité sociale - CMSS) or with the attending physician or any other health practitioner are allowed at any time but must be documented by the worker on sick leave.

Protection against dismissal

Absences due to incapacity for work can not be:

  • considered to be an unjustified absence;
  • nor be deducted from the employee's annual holiday allowance.

If an employee has fulfilled their obligations in terms of information (informing their employer on the first day and providing a medical certificate on the third day at the latest), they are protected against dismissal during a maximum period of 26 weeks from the date of the beginning of their sick leave.

During this 26-week period, the employer may neither dismiss the employee with notice nor call him to a preliminary interview in view of dismissal with notice nor dismiss him for serious misconduct which took place prior to the sick leave.

However, an employee is not protected against dismissal:

  • if they are absent because of an incapacity for work due to a crime or misdemeanour in which they participated voluntarily (e.g.: incapacity for work due to a traffic accident caused by the employee while driving under influence and without a valid driving licence);
  • if the letter of dismissal was received by the employee before the employer was informed of the employee's sick leave;
  • or if for no valid reason, the employee has repeatedly missed additional medical appointments organised by their employer;
  • or, depending on the case, if the employee has not fulfilled the obligations in terms of information.

Employers may terminate the employment contract after a period of 26 weeks of incapacity for work.

Informing the employer on the first day of absence due to sick leave and providing the employer with the medical certificate within 3 days of absence are two concurrent essential conditions entitling an employee to receive protection against dismissal.

If one of the conditions is not fulfilled, an employee is not protected against dismissal during a sick leave. However, these conditions do not affect the employee's salary.

Therefore, if an employee submits a medical certificate to their employer, even after the 3-day deadline, the employee is entitled to their salary for the period indicated on the medical certificate if the sick leave occurs during the continuation of pay period ('Lohnfortzahlung').

Administrative check on employees

Administrative checks on employees who are absent from work due to sickness or accident may be initiated by the department for control and management of certificates of incapacity for work (service Contrôle et gestion des certificats d'incapacité de travail) of the National Health Fund (Caisse Nationale de Santé - CNS) as well as upon justified request from the employer.

A check may be carried out during the period of continuation of pay by the employer or during the period when the CNS takes charge of the financial compensation.

To request an administrative check, the employer has to:

Following their request, the employer receives written confirmation from the department responsible for checking on employees on sick leave (by fax or e-mail), as well as the registration number of their request.

If the employee returns to work before the term of their sick leave expires, the employer must immediately inform the CNS.

The administrative check carried out be the CNS is a control measure to verify whether the worker on sick leave is at home. The control can take place between 8.00 and 21.00. These controls can concern both resident and non-resident workers and may be carried out as from the first day of incapacity for work. Thus, with respect to cross-border workers residing in France, the CNS may submit a request to the competent health fund (Caisse primaire d'assurance maladie - CPAM) in the French department where the insured person has their main place of residence. The CPAM can mandate a general practitioner practising in France to go to the employee's domicile for the purpose of checking on the employee.

The administrative check produces a certificate of presence, or of infraction in the event of absence of the worker. The physician noting the worker's absence from home during an administrative check will leave a note for the worker. The worker on sick leave must then provide an explanation for their absence within 3 days of the administrative check.

After this deadline, if the employee has not provided a valid reason for their absence, the employer will be informed of the result of the administrative check.

If the employer wishes to make a new request for the same employee on sick leave, they may do so at the earliest 30 days after the last request.

Additional medical examination

A medical certificate does not constitute irrefutable proof of the employee's incapacity for work.

The employer may have doubts with regard to whether the employee is actually ill or may suspect that the certificate was only issued as a friendly service to the patient.

The employer may therefore request the employee to attend an additional medical examination at a doctor's practice of their choice.

If the employee consistently refuses the additional medical examination without giving reasons, they are no longer protected against dismissal.

The occupational health practitioner at the social security may also summon an employee for an additional medical examination in order to protect the financial interests of the National Health Fund (Caisse Nationale de Santé - CNS) against any abuse.

In the case of contradictory opinions of the attending physician and the doctor carrying out the additional medical examination, it is recommended that the services of a third doctor be requested in order to reach a decision.

In fact, an additional medical examination alone is not sufficient to prove the fictitious nature of the incapacity for work.

The employer must provide other elements of proof (for example, a second additional medical examination where it was noted that the employee is fit for work and, depending on the case, the employee's evenings out or activities that are in contradiction with the invoked state of health).

Progressive return to work

The request for a progressive return to work has to be made by using the standardised form "Demande de reprise progressive du travail pour raisons thérapeutiques", on which the attending physician will attest that a progressive return to work for therapeutic reasons will improve the insured person's state of health.

The form has to be duly completed and signed by the attending physician and is subsequently submitted to the employer who has to give their consent.

 In order to benefit from progressive return to work, the employee is required to:

  • have been unable to work for at least one month out of the 3 months preceding the request; and
  • be unable to work at the time of the request.

The progressive return to work for therapeutic reasons may only begin once the CNS has given its consent, based on a reasoned opinion from the Medical Board of the Social Security.

The return to work as well as the work carried out must be recognised to have a beneficial effect on the employee's state of health and be attested by the attending physician.

Financial compensation is due throughout this period. If the CNS is responsible for the paying the compensation, a certificate of a 100 % incapacity for work has to be presented.


Forms / Online services

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Request for administrative control

To complete your application, the information about you collected from this form needs to be processed by the public administration concerned.

That information is kept by the administration in question for as long as it is required to achieve the purpose of the processing operation(s).

Your data will be shared with other public administrations that are necessary for the processing of your application. For details on which departments will have access to the data on this form, please contact the public administration you are filing your application with.

Under the terms of Regulation (EU) 2016/679 on the protection of natural persons with regard to the processing of personal data and on the free movement of such data, you have the right to access, rectify or, where applicable, remove any information relating to you. You are also entitled to withdraw your consent at any time.

Additionally, unless the processing of your personal data is compulsory, you may, with legitimate reasons, oppose the processing of such data.

If you wish to exercise these rights and/or obtain a record of the information held about you, please contact the administration in question using the contact details provided on the form. You are also entitled to file a claim with the National Commission for Data Protection (Commission nationale pour la protection des données), headquartered at 15, boulevard du Jazz L-4370 Belvaux.

By submitting your application, you agree that your personal data may be processed as part of the application process.

Online procedure

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Demande de contrôle administratif en ligne

Les informations qui vous concernent recueillies sur ce formulaire font l’objet d’un traitement par l’administration concernée afin de mener à bien votre demande.

Ces informations sont conservées pour la durée nécessaire par l’administration à la réalisation de la finalité du traitement

Les destinataires de vos données sont les administrations compétentes dans le cadre du traitement de votre demande. Veuillez-vous adresser à l’administration concernée par votre demande pour connaître les destinataires des données figurant sur ce formulaire. Conformément au règlement (UE) 2016/679 relatif à la protection des personnes physiques à l'égard du traitement des données à caractère personnel et à la libre circulation de ces données, vous bénéficiez d’un droit d’accès, de rectification et le cas échéant d’effacement des informations vous concernant. Vous disposez également du droit de retirer votre consentement à tout moment.

En outre et excepté le cas où le traitement de vos données présente un caractère obligatoire, vous pouvez, pour des motifs légitimes, vous y opposer.

Si vous souhaitez exercer ces droits et/ou obtenir communication de vos informations, veuillez-vous adresser à l’administration concernée suivant les coordonnées indiquées dans le formulaire. Vous avez également la possibilité d’introduire une réclamation auprès de la Commission nationale pour la protection des données ayant son siège à 15, boulevard du Jazz L-4370 Belvaux.

En poursuivant votre démarche, vous acceptez que vos données personnelles soient traitées dans le cadre de votre demande.

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