The Schengen Area ( ) is an area comprising 26 European states that have officially abolished all passport and all other types of border control at their mutual borders. The area mostly functions as a single jurisdiction for international travel purposes, with a common visa policy. The area is named after the 1985 Schengen Agreement.
22 of the 28 EU member states participate in the Schengen Area. Of the six EU members that are not part of the Schengen Area, four—Bulgaria, Croatia, Cyprus, and Romania—are legally obliged to join the area in the future, while the other two—Ireland and the United Kingdom—maintain opt-outs. The four European Free Trade Association (EFTA) member states, Iceland, Liechtenstein, Norway, and Switzerland, are not members of the EU, but have signed agreements in association with the Schengen Agreement. Three European microstates that are not members of the European Union but which are enclaves or semi-enclave within an EU member state—Monaco, San Marino, and Vatican City—are de facto part of the Schengen Area.
The Schengen Area has a population of over 400 million people and an area of 4,312,099 square kilometres (1,664,911 sq mi). About 1.7 million people commute to work across a European border each day, and in some regions these people constitute up to a third of the workforce. Each year, there are 1.3 billion crossings of Schengen borders in total. 57 million crossings are due to transport of goods by road, with a value of €2.8 trillion each year. The decrease in the cost of trade due to Schengen varies from 0.42% to 1.59% depending on geography, trade partners, and other factors. Countries outside of the Schengen area also benefit. States in the Schengen Area have strengthened border controls with non-Schengen countries.