Treaties are the primary law of the European Union. This page links to a few good sources for EU treaties. For current, consolidated versions of the treaties, EUR-Lex and Europa are the best sources.
Great source for treaties currently in force (consolidated versions of the Treaty on European Union and the Treaty on the Functioning of the European Union, along with the Charter of Fundamental Rights of the European Union). Also include links and search options to find: texts of founding treaties; accession treaties; and other treaties and protocols.
"Text of treaties between member states of the European Union, including the founding treaties establishing the European Coal and Steel Community (1951), the European Economic Community (1957), and the European Atomic Energy Community (1957); accession documents that enlarged the European communities; treaties of amendment such as the Single European Act (1986); and the Treaty of European Union (Maastricht Treaty, 1992)."
