Switzerland recognises the acquisition of Swiss citizenship through paternal or maternal descent, through jus sanguinis, regardless of place of birth.
Acquisition of Swiss citizenship
According to the Swiss Citizenship Act (SCA):
Art. 1 SCA Acquisition by descent
1 The following persons are Swiss citizens from birth:
a. a child whose parents are married to each other and whose father or mother is a Swiss citizen;
b. a child of a female Swiss citizen who is not married to the child's father.
2 A minor foreign child of a Swiss father who is not married to the child's mother acquires Swiss citizenship as if at birth by establishing the father's paternity.
3 If a minor child who acquires Swiss citizenship under paragraph 2 has children, the children also acquire Swiss citizenship.
A child born abroad who has another citizenship and at least one of whose parents is Swiss loses their Swiss citizenship upon reaching the age of 25 unless a Swiss authority abroad or in Switzerland is notified of their birth by their 25th birthday or if they have declared in writing that they wish to retain Swiss citizenship. Children of a person who has lost Swiss citizenship under Art. 7, para. 1 SCA also lose their Swiss citizenship.
Swiss citizenship can be acquired through naturalisation by applying to the competent authority in Switzerland or by official decree of the competent authority:
the cantonal authority of the place of residence in Switzerland in case of an application for ordinary naturalisation;
the State Secretariat for Migration (SEM) in case of an application for simplified naturalisation or reinstatement of citizenship filed abroad.
Applicants living abroad must submit their naturalisation/renaturalisation requests to the Swiss representation that covers their place of residence.