The Constitution of Luxembourg (; ; German: Luxemburgische Verfassung) is the supreme law of the Grand Duchy of Luxembourg. The modern constitution was adopted on 17 October 1868.
Whilst the constitution of 1868 marked a radical change in Luxembourg's constitutional settlement, it was technically an amendment of the original constitution. That original constitution was promulgated on 12 October 1841, came into effect on 1 January 1842, and was acutely amended on 20 March 1848, and again on 27 November 1856.
Luxembourg first emerged as a legitimate principality in the 14th century. It lived under successive Burgundian, Spanish, French, Austrian sovereignty, until 1815 when the Congress of Vienna erected it into a grand duchy and assigned it to William I, King of the Netherlands. However, it was not annexed to the Kingdom of the Netherlands; instead, it formed a personal union within the German Confederation created by the Congress of Vienna.
When the 1866 Austro-Prussian War led to the dissolution of the German Confederation, the Treaty of London (11 May 1867), which was drawn up in the resolution of the Austro-Prussian War, established the independence of the German-speaking part of Luxembourg.In 1830, Belgium revolted against its union with the Netherlands causing Luxembourg to be divided between Belgium and Holland.
Through the political instability from 1815 to 1868, Luxembourg was governed by five different constitutional documents. The recognition of Luxembourg as an independent state in 1868 called for yet another revision of the fifth Constitution of 1856. William III agreed to grant a more liberal constitution which went on to constitute the modern 1868 Constitution which is in use today. The new Constitution confirmed the principle of constitutional monarchy and the international status of Luxembourg, declaring it to be an "independent, indivisible, inalienable and eternally neutral" state. Although it was first adopted on 17 October 1868, the Constitution has since been amended many times in order to adapt with the evolving times.
Nature of the Constitution In Luxembourg, the Constitution is considered the supreme legal rule of the state. The written constitution is considered to be "evolutionary" in nature, and has continued to develop concurrently to historical and political events in Luxembourg over the last 200 years, instead of serving as a normative force. Thus, the 1868 Constitution is a living constitution and has been amended many times since its inception, most recently in 2025. It comprised 132 Articles, divided into 12 chapters, dedicated to describing the role of the Grand Duke, the rights and liberties of citizens and the power separation in the State.
Under the present Constitution, the Grand Duchy is a democratic, free, independent and indivisible state headed by a constitutional monarch and governed by a system of parliamentary democracy. It specifically outlines the roles of the executive, legislative and judicial branches of Luxembourg's system of government, as well as the Conseil d'Etat, which is responsible for moderating parliamentary procedure with respect to the Constitution.
Historical Belgian and Dutch influences Although it has since been revised many times, Luxembourg's 1868 Constitution is one of Europe's oldest written constitutions remaining in force, with many of its provisions even dating back to the first Constitution of the country, granted by William II of the Netherlands in 1841. The 1841 Chartered Constitution therefore greatly resembled the Dutch Constitution, the Grondwet of 1815, vesting all powers within the grand duke and creating legislative, executive and judicial bodies with very limited powers. The authoritarian regime prescribed by the 1841 Charter was not well received in Luxembourg society, prompting William II to succumb to demands for a revised, more liberal Constitution in 1848.
For the 1848 Constitution, a majority of the new constitutional provisions were inspired by the Belgian Constitution of 1831. This is because a part of Luxembourg had been governed under the 1831 Belgian Constitution in the previous decade as a consequence of the Belgian Revolution. The influence of the Belgian Constitution is still evident in the present, revised 1868 Constitution of Luxembourg. For instance, Article 87 provides for a Superior Court of Justice in Luxembourg. This is inspired by Article 147 of the Belgian Constitution which provides for a Court of Cassation to oversee uniformity and the legality of justice for the whole of Belgium.
Therefore, given its historical connections to the Netherlands and Belgium, Luxembourg's constitutional tradition has been strongly influenced by the constitutional traditions of these countries.
Institutional landscape The present Constitution of Luxembourg attributes the separation of powers as follows: executive power is exercised by the Grand Duke and the Government while legislative power is conferred upon the unicameral parliament (Chamber of Deputies) and the joint action of Government and the Council of State. Judicial power is attributed to courts and tribunals which function independently.
Grand Duke The Constitution establishes that the sovereign power resides in the Nation. According to Article 32, the Grand Duke, Guillaume Jean Joseph Marie (2025 – present), exercises this sovereign power, conforming to this Constitution and to the laws of the country. He has only those powers that the Constitution and laws expressly confer upon him. Both within and outside the borders of Luxembourg, the Grand Duke is meant to express the identity of the country. He symbolises its independence, the unity of the territory and the permanence of the state.
The Constitution places the Grand Duke in a unique position outside common law. Article 1 of the Constitution provides that the person of the Grand Duke is inviolable. In other words, he cannot be tried by any court and he cannot be asked to be held accountable for his actions at all, from a penal or political standpoint. The Grand Duke's inviolability and unaccountability ensure the stability of the monarchical institution and his impartiality with respect to the political world.
Through Article 34, he is also tasked with making the regulations and decisions necessary for the execution of the laws. Through a process of "enactment", the Grand Duke can make the law enforceable. The law is published in the Official Journal of the Grand Duchy of Luxembourg. Subsequent to his legislative powers, the Grand Duke's regulatory power consists in making the regulations and administrative orders required for the enforcement of laws and treaties. In some cases he may delegate this power to the members of his government.
Hence, while the Grand Duke directly participates in legislative power, he exercises executive power only through his government, who he appoints on the advice of the elected Prime Minister.
The Grand Duke was originally vested with considerable reserve powers. However, from 1890 onward, most monarchs have limited themselves to a mostly representative role, a convention which was codified by constitutional amendment in 1919.
Government According to Article 51 of the Constitution places the Grand Duchy of Luxembourg under a governmental regime of parliamentary democracy. Hence, while Article 76 provides that the Grand Duke will regulate the organisation of the government, he is bound by the democratic principle in practice.
The Grand Duke thus has the power to appoint a formateur to charge with building a Government. The formateur usually becomes Prime Minister and introduces the members of the Government to the Grand Duke, who appoints and swears them in. Article 76 provides that the government must have at least three members, whom the Grand Duke has the power to appoint and dismiss (this power to dismiss has yet to be exercised in 2021). However, in practice, the ministers he appoints must have the confidence of the voting majority. Customarily, therefore, the Grand Duke only appoints a Prime Minister on the basis of the results of the election.
Article 78 of the Constitution provides that members of the Government ('ministers') are responsible. Essentially, for an act issued by the Grand Duke to come into force, it must be countersigned by a member of the government who assumes full responsibility for it (Article 45). They are responsible to the Chamber of Deputies of the State, which has the power to withdraw its confidence in the ministers, obliging them to resign.
Chamber of Deputies (Parliament) Luxembourg's parliament, known as the Chambre des Députés (Chamber of Deputies) represents the country and primarily exercises legislative power. According to Chapter IV of the Constitution, the law of the land regulates the organization of the Chamber. The Chamber is composed of 60 Deputies, elected through a direct election conducted in the four circumscriptions of the country. Article 51 provides that the Deputies are elected on the basis of universal suffrage, on [a party] list ballot, following the rules of proportional representation, conforming to the principle of the smallest electoral quotient and following the rules to be determined by the law.
The Chamber meets each year in ordinary session at the time specified by its regulations. The sittings of the Chamber, which require majority presence, are public (Article 61) and every resolution is taken with the absolute majority of votes (Article 62). According to Article 66, the Chamber has the right to amend and divide the articles and amendments proposed.
The Chamber of Deputies also acts as a check back mechanism against the ministerial actions of the government. If the Chamber disapproves of the policy of one or several ministers or of the entire government, it has the power to express its disagreement, either via a negative vote on a specific agenda proposed by the government, or by rejecting a government bill presented by the ministers. In the worst case, when the Chamber of Deputies withdraws its confidence (motion of censure) in the ministers, the political responsibility of ministers obliges them to resign.
Council of State The Council of State originates from the preliminary Constitution of 1856 – its organization and obligations are both regulated by the law. Article 83 of the Constitution establishes that the Council of State is called to give its opinion on the bills and proposals of law and amendments, which have been and are proposed, as well as on all other questions which have been referred to it by the Government or by the laws. The Conseil d'Etat acts as the primary advisory organ and the 'guardian of the Constitution' and exercising a moderating function within the parliamentary procedure similar to that of a second chamber.
Until 1996, the Council of State also acted as the administrative court, but this function was transferred to the newly established Administrative Tribunal and Administrative Court in order for matters to be heard by an independent court. The Constitution also provides that the Council of State will have a true right of suspensive veto for legislative matters.
Courts and Tribunals Article 49 of the Constitution provides that justice is rendered in the name of the Grand Duke by the courts and the tribunals. The Constitution grants courts and tribunals independence of function. Luxembourg has two jurisdictions, including an ordinary judicial branch which deals with civil disputes, disputes of a penal nature and disputes regarding political rights, and an administrative branch which rules on disputes with the authorities (Articles 84, 85). By establishing two systems, the constituent assembly has tried to avoid the ordinary courts' trespassing on the territory of the executive and thus infringing the principle of the separation of powers.