Short for: Confoederatio Helvetica, the Latin name for the country.

CH for Confoederatio Helvetica is the international abbreviation for Switzerland.

For historical reasons, Switzerland’s official name is still the “Helvetic Confederation” (in Latin: Confoederatio Helvetica) from which the country’s international abbreviation, CH, is derived. However, this is in fact a misnomer: a confederation is an alliance of autonomous entities. Since 1848 Switzerland has been a federation: a grouping of entities with a central authority.

The word Helvetic refers to the Helvetians, one of the many Celtic tribes living in what is now Switzerland at the time of the Roman conquest.

I obtained this information from http://www.swissworld.org/eng/swissworld.html?siteSect=701&sid=4100094&rubricId=15010

Exactly!

Latin name, and german, french, italian and ramonche, his four officials languages.

Confœderatio Helvetica
Schweizerische Eidgenossenschaft
Confédération Suisse
Confederazione Svizzera
Confederaziun Svizra

Ch stands for the roman name for Switzerland. Confederation Helvetica

one thing to add to the above mentioned. Using the CH prevents the Swiss from prioritizing one of its four official languages when it comes to abreviations of its name (i.e. Schweiz, Svizzera, Suisse, Svizra), such as in sports, when Swiss sportsmen/women are usually mentioned with SUI (from Suisse) – another special case, as e.g. the Olympic Organisations with very few exceptions use the English version of a country for abrevisions (e.g. GER for Germany).