Slovenia is a member of the European Union.
The four countries forming the European Free Trade Association (EFTA) are not EU members, but have partly committed to the EU's economy and regulations: Iceland, Liechtenstein and Norway, which are a part of the single market through the European Economic Area, and Switzerland, which has similar ties through bilateral treaties
 According to a 2019 study of the member states who joined from 1973 to 2004, "without European integration, per capita incomes would have been, on average, approximately 10 per cent lower in the first ten years after joining the EU

