Postal codes in Switzerland and Liechtenstein
On 26 June 1964, Swiss Post introduced postal codes as the third country after Germany (1941) and the United States (1963).
In Switzerland, the postal codes have four digits. As with the postcode system introduced in Germany in 1993, a municipality can receive several postcodes. A locality (settlement) having its own postal code does not mean that it is an independent political municipality, but only that it is an official locality. In addition, a postcode can include several political communes (e.g.: 3048 Worblaufen, includes parts of the communes of Bern and Ittigen) or several cantons (e.g.: 8866 Ziegelbrücke, includes parts of the cantons of Glarus and St. Gallen), which is why it is not possible to assign it unambiguously in both directions. In addition, it is often not possible to assign a unique postcode to post offices (post boxes) in larger cities. For this reason, six-digit postcodes are used internally.
The Principality of Liechtenstein is also included in the Swiss postal code system, as is the German enclave of Büsingen am Hochrhein, which has its own Swiss postal codes in addition to its national one, D-78266. Before January 2020, the Italian enclave of Campione d'Italia also had a Swiss postcode, CH-6911, but this ceased to be valid, and all mail requires the use of the Italian postcode. This followed the enclave's entry into the European Union's Customs Area. Also in Italy, Swiss Post previously held an office in Domodossola with the code CH-3907. This is now used for the village of Simplon.