Switzerland’s present-day national border is based on the 1815 Treaty of Vienna.

The course of the border has undergone significant changes since then due to various construction projects (Geneva-Cointrin airport, customs posts in Chiasso and Bardonnex, dams in Livigno, Emosson and Lei, etc.). Since no country has the right to claim the territory of another nation, these modifications always resulted in the exchange of equally sized territories.

Because the border is a constituent of Switzerland’s sovereign territory, any modification of its course must be affirmed by Parliament and is subject to a facultative referendum. All treaties and agreements with neighbouring countries that concern Switzerland’s sovereign territory are archived in the official compendium of federal legislation.

The Federal Council has the powers to independently conclude treaties with foreign countries concerning national borders, provided these merely concern adjustments or other minor changes to the territory.

swisstopo is the federal authority responsible for the specification, marking and surveying of the national border, as well as for the administration and documentation of all the associated processes.

For each neighbouring country there is a joint commission which on the Swiss side includes representatives of swisstopo, the Federal Department of Foreign Affairs (FDFA), the Federal Customs Administration (FCA) and official surveyors from the respective cantons. These commissions are responsible for all matters pertaining to the definition of the course of the national borders.