Complaints and appeals

Whatever my situation, the CNS strives to provide me with the best possible service in the shortest possible time. Its various departments work diligently to address my requests and respond to my questions.

However, if I feel that I have not been treated appropriately during an exchange with the CNS, there are several ways for me to file a claim or lodge an objection.

Everything I need to know

With the wide range of services and benefits it offers, the CNS may have to provide me with information or make decisions that affect me.

By clicking on the relevant tab below, I can find out how to make a complaint to the CNS and how to contest various decisions.

I have a complaint, the CNS listens to me!

I have a complaint about the quality of service at the counter or over the phone, response times via telephone or email, or an issue with the management of my file?

I can submit my complaint through the following channels:

  • By email
  • By post
  • By telephone, ensuring I have my 13-digit identification number ready
  • In person, by visiting the agency to make an appointment

A CNS representative will make every effort to find a solution that meets my needs.

I have received a simple decision and would like to request a presidential decision

I have received a simple decision from the National Health Fund (CNS) and I do not agree with it.

In this case, I can request a presidential decision.

The CNS will then send me by post a written decision, signed by the President or their delegate, with an information leaflet on how to appeal.

I have received a presidential decision and would like to request a decision from the Board of Directors

I have received a presidential decision from the National Health Fund (CNS) and I do not agree with it.

In this case, I can contest it by requesting a decision from the CNS Board of Directors.

What is the deadline?

My written objection must be sent by registered post with acknowledgement of receipt to the CNS Board of Directors within forty days of notification.

My written objection does not have to take any particular form. It may be written on plain paper. A lawyer is not required.

I have received a decision from the Board of Directors and I would like to request a ruling from the Social Security Arbitration Tribunal

I have received a decision from the Board of Directors of the National Health Fund (CNS) and I do not agree with it.

If so, I can challenge it by lodging an appeal with the Social Security Arbitration Tribunal (Conseil arbitral de la sécurité sociale CASS). The CASS is a court of first instance to which any decision taken by the Board of Directors may be appealed.

What is the deadline?

I must lodge my appeal within forty days of being notified of the Board's decision.

What is the procedure?

The procedure is cost-free and does not require the services of a lawyer.

I must submit my application in the form of a simple request, on plain paper, and in as many copies as there are parties involved.

I may defend myself alone or be represented by a professional or trade union organisation or by a lawyer.

The application and the documents submitted must be signed by:

  • by myself;
  • by my legal representative;
  • or by my authorised representative, who may be the representative of my professional organisation or trade union.

The application must state:

  • the subject of the request;
  • my full name;
  • my identity numbers;
  • my profession;
  • my address;
  • the capacity in which I am acting;
  • a summary of the arguments on which my application is based.

If my representative is not a lawyer, they must present a special power of attorney, at the latest during the oral hearing and before it begins.

Can I contest a CASS decision?

The CASS rules at first and last instance up to a value of €1,250. In other words, if my dispute does not exceed this value, the CASS judgment is final and I cannot appeal.

The final judgements handed down by the CASS may be appealed to the Court of Cassation (Cour de cassation). This requires the services of a barrister.

I'll find out more under 'Appeal to the Court of Cassation'.

Above this amount, the dispute may be appealed to the High Council of Social Security (Conseil supérieur de la sécurité sociale CCSS).

I have received a ruling from the Social Security Arbitration Tribunal and I would like to request a ruling from the High Council of Social Security

I have received a ruling from the Social Security Arbitration Tribunal (Conseil arbitral de la sécurité sociale CASS) and I do not agree with it:

  • If the value of the dispute does not exceed €1,250, I can no longer appeal. The decision of the CASS is final.
  • If the value of the dispute exceeds €1,250, I can lodge an appeal.

I can challenge the ruling of the CASS by lodging an appeal with the High Council of Social Security (Conseil supérieur de la sécurité sociale CSSS). The CSSS is a court of second instance before which judgements made by the CASS, for disputes worth more than €1,250, can be challenged.

What is the deadline?

I must lodge an appeal in the form of a petition within a specified deadline from the date of notification of the CASS judgment. The deadline depends on my country of residence:

  • Luxembourg: 40 calendar days
  • in a European territory, a member state of the European Union or the European Free Trade Association, Andorra, Gibraltar, the Vatican City, the Åland Islands, the Channel Islands, the Faroe Islands or the Isle of Man: 55 calendar days
  • in another European country, excluding Turkey and Russia: 65 calendar days
  • in another country or territory of the world: 75 calendar days

What is the procedure?

The procedure is free and does not require the services of a lawyer.

I must submit my application in the form of a simple request, on plain paper, and in as many copies as there are parties involved.

I may defend myself alone or be represented by a professional or trade union organisation or by a lawyer.

The application and the documents submitted must be signed by :

  • by myself;
  • by my legal representative;
  • or by my authorised representative, who may be the representative of my professional organisation or trade union.

The application must state:

  • the subject of the request;
  • my full name;
  • my identity numbers;
  • my profession;
  • my address;
  • the capacity in which I am acting;
  • a summary of the arguments on which my application is based.

If my representative is not a lawyer, they must present a special power of attorney, at the latest during the oral hearing and before it begins.

Can I contest a CSSS judgment?

The final judgements of the CASS and the judgements of the CSSS may be appealed to the Court of Cassation. This requires the services of a barrister.

Find out more under 'Appeal to the Court of Cassation'.

What is an appeal in cassation and how do I lodge it?

An appeal in cassation is a means of appealing against a decision that has been handed down at last instance, in other words when the decision can no longer be appealed.

I can lodge an appeal in cassation to the Court of Cassation (Cour de cassation) against:

  • final decisions handed down by the Social Security Arbitration Tribunal (Conseil arbitral de la sécurité sociale CASS) ;
  • rulings by the High Council of Social Security (Conseil supérieur de la sécurité sociale CSSS).

Please note that an appeal is only admissible in respect of:

  • a breach of the law, or
  • a violation of essential procedural requirements or those mandated under penalty of nullity.

I must be represented by a lawyer.

Other organisations that can help me

If necessary, I can also turn to other organisations outside the legal system. For example :

  • The Ombudsman's mandate is to seek an amicable solution if I have a dispute with a public institution or administration.
  • Patientevertriedung ASBL informs me about my rights and duties. If I have a specific problem, I can seek advice from the Patientevertriedung.
  • The mission of the Medical College is to ensure that the ethical rules governing the practice of the medical professions are respected.

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