Switzerland is in the Schengen zone. This means that in order to enter Switzerland you must follow all requirements set forth by the Schengen agreement. This agreement helped dissolve some boundaries within Europe and helps allows for others who need visas to be processed quickly and more efficiently.
United States citizens are not required to enter obtain a visa before entering the Schengen zone if they intend on entering the area for purposes of tourism, and for stays less than 90 days.
All legal residents of the United States, Canada and Great Britain are required to obtain a visa for all purposes entering the Schengen zone. This was set forth after a Schengen Agreement revision in 2008.
All United States residents who wish to enter Switzerland must apply for a Schengen visa. They must complete a visa application (see Resources), submit an additional passport photo, submit all American residency paperwork, submit their national passports, and pay the visa application fee to the nearest Swiss consulate. All visa application forms and documentation must be submitted to the nearest Swiss consulate/ embassy.
After the United States resident has been issued a Schengen visa, he will be allowed to enter Switzerland and any other country within the Schengen zone for a period of three months. He also will be able to return to Switzerland as many times as he would like during those three months.