Do I need a Schengen visa?

My nationality Obligation to hold a visa (yes/no)
Nigeria  yes (V) 
Chad   yes (V)  
Niger  yes (V) 

(V)
Third state members in possession of both a valid residence permit issued by a Schengen member state or a valid type D visa and a recognized travel document are exempt from visa requirements.

Other nationalities

For other nationalities, please refer to the list on the webpage of the State Secretariat for Migration (SEM).

SEM – Overview of ID and visa provisions according to the nationality (Annex 1, List 1: nationality)

If you are obliged to hold a visa, please apply for it and refer to the information on the webpage:

Where to apply for a Schengen visa?

If you are not obliged to hold a visa, you are allowed to enter Switzerland resp. the Schengen territory and stay up to 90 days within a 180-day period without any visa.