Treaties form the basis of EU and are the primary legislation of the European Union. Treaties set out common objectives, rules for institutions, how decisions are made and the relationship between member states and EU. Treaties give EU institutions power to adopt legislation, which member states then have to implement. Treaties can be amended in order to make make the EU more efficient and transparent, prepare for new member countries and introduce new areas of cooperation.
Treaties currently in force:
OJ C 306, 17.12.2007
Treaty on the Functioning of the European Union (Consolidated version 2016)
OJ C 202, 7.6. 2016
Treaty on European Union (Consolidated version 2016)
OJ C 202, 7.6.2016
Charter of Fundamental Rights of the European Union (2012)
OJ C 326, 26.10.2012, p. 391-407
Treaty establishing the European Atomic Energy Community ( Consolidated version 2012)
OJ C 327, 26.10.2012
Consolidated legislation includes amendments and corrections. It makes the treaties easier to read and understand. However consolidated texts are intended for use as documentation tools and they have no legal value. For legal purposes please refer to the texts published in the OJ.
The Founding treaties of the European Union were:
Treaty establishing the European Coal and Steel Community (1951)
Entered into force: 23 July 1952
Expired: 23 July 2002
Purpose was to ease tensions after WWII and create interdependence in coal and steel so that one country could no longer mobilise its armed forces without others knowing.
Treaties of Rome:
Treaty establishing European Economic Community, EEC (1957)
Treaty establishing the European Atomic Energy Community, EURATOM (1957)
Entered into force: 1 January 1958
The European Economic Community (EEC) and the European Atomic Energy Community (Euratom) was wet up and European integration began with general economic cooperation.
Treaty on European Union - Maastrich Treaty (1992)
Entered into force: 1 November 1993
Purpose was to prepare for European Monetary Union and introduce elements of a political union (citizenship, common foreign and internal affairs policy).
The treaty established the European Union and introduced the co-decision procedure, giving Parliament more powers in decision-making. Also new forms of cooperation between EU governments were introduced – for example on defence and justice and home affairs.
Merger Treaty - Brussels Treaty (1965)
Entered into force: 1 July 1967
Purpose of the Treaty was to streamline the European institutions. It created a single Commission and a single Council to serve the then three European Communities (EEC, Euratom, ECSC). The Treaty was repealed by the Treaty of Amsterdam.
Single European Act (1986)
Entered into force: 1 July 1987
The Single European Act's purpose was to reform the institutions in order to prepare Portugal and Spain's membership and speed up decision-making in preparation for the single market. The Act extended the qualified majority voting in the Council (making it harder for a single country to veto proposed legislation), created the cooperation and assent procedures, giving Parliament more influence.
Treaty of Amsterdam (1997)
Entered into force: 1 May 1999
The Treaty's purpose was to reform the EU institutions in preparation for the arrival of future member countries. It changed the amendment, renumbering and consolidation of EU and EEC treaties. It also introduced a more transparent decision-making (increased use of the co-decision voting procedure).
Treaty of Nice (2001)
Entered into force: 1 February 2003
The Treaty reformed the functioning of the institutions in order to prepare for the enlargement of the EU. It introduced methods for changing the composition of the Commission and redefining the voting system in the Council.
The Treaty establishing a constitution for Europe (2004)
Purpose was similar to the Lisbon Treaty – was signed but never ratified.
Treaty of Lisbon amending the Treaty on European Union and the Treaty establishing the European Community (2007)
Entered into force: 1 December 2009
The purpose of the Lisbon Treaty was to make the EU more democratic, more credible and efficient as a global actor and this way better able to address global problems.
More power was given to the European Parliament, Council's voting procedures were changed, citizens' initiative, a permanent president of the European Council, a new High Representative for Foreign Affairs and a new EU diplomatic service were introduced. The Lisbon treaty aimed at clarifying the powers of the EU and member states.
Charter of Fundamental Rights of the European Union (2007)
Entered into force: together with the Lisbon Treaty, on December 2009
The purpose of the Treaty was to consoliate the fundamental rights applicable at European Union (EU) in a charter. The general principles set out in the 1950 European Convention on Human Rights and those derived from the constitutional traditions common to EU countries were included in the Charter. Also the fundamental rights that apply to EU citizens as well as the economic and social rights contained in the Council of Europe Social Charter and the Community Charter of Fundamental Social Rights of Workers were included. It would also reflect the principles derived from the case law of the Court of Justice and the European Court of Human Rights.
Cronological list of treaties and links to official texts.