Swiss nationality law

Swiss citizenship is the status of being a citizen of Switzerland and it can be obtained by birth or naturalisation.
The Swiss Citizenship Law is based on the following principles:
Swiss nationals are citizens of their municipality of origin, their canton of origin, and the Confederation, in that order: a Swiss citizen is defined as someone who has the bourgeoisie of a Swiss municipality (article 37 of the Swiss Federal Constitution). They are entered in the family register of their place of origin. The manner by which Swiss citizens acquire their place of origin differs depending on whether they acquired Swiss citizenship by filiation (jus sanguinis), ordinary naturalisation, or facilitated naturalisation. Marriage has in and of itself no effect on the places of origin of the spouses.
Acquisition of Swiss citizenship.
Acquisition by filiation.
A child acquires Swiss citizenship at birth by either:
A child of a Swiss father not married to the mother is considered Swiss by birth when a link of paternity is declared; any children of that child also acquire Swiss citizenship by filiation.
The child of two Swiss citizens who are married at the time of the child's birth acquires the places of origin of the parent whose surname the child acquires.
Foundlings.
A foundling acquires Swiss citizenship and the citizenship of the canton in which they are found. The canton decides which place of origin the child receives. Once paternity is determined, the child loses Swiss citizenship, unless this would leave him or her stateless.
Adoption.
A child adopted by a Swiss parent acquires the place of origin of the Swiss parent, thereby acquiring Swiss nationality.
Naturalisation.
Ordinary naturalisation.
Ordinary naturalisation in Switzerland is a cantonal competency but regulated by federal legislation. 
On 20 June 2014, the two Chambers of the Swiss Parliament passed the Total Revision of the Federal Law Concerning the Acquisition and Loss of Swiss Nationality ("Révision totale de la loi sur l'acquisition et la perte de la nationalité suisse"). The Law, first introduced in 2011 by the Swiss federal government, aimed to lower, among other requirements, the residency requirement from 12 years to 8 years. During the parliamentary debates and the ensuing disagreements between the more conservative National Council (lower house) and the more liberal Council of States (upper house), the residency requirement was increased to 10 years. The time spent in Switzerland between the ages of 8 and 18 is doubled when counted for purposes of applying for naturalisation, however, an applicant must have spent at least 6 years in Switzerland. The law also requires cantons to set a minimum residency requirement of between 2 and 5 years, as well as requiring applicants to have a permanent residency permit (Autorisation d'établissement), which is commonly referred as a C permit. Additionally, time spent in Switzerland with temporary admission ("Permis d'admission provisoire") is halved counting the years spent in Switzerland for the purposes of naturalisation. The 2014 Total Revision of the Federal Law Concerning the Acquisition and Loss of Swiss Nationality entered into force on 1 January 2018.
Applications for naturalisation submitted prior to the entry into force of the new nationality law will continue to be processed under the 1952 law.
The federal nationality law of 2014 imposes two formal conditions which an applicant for naturalisation must satisfy:
In addition to the aforementioned formal conditions, the federal nationality law of 2014 also imposes material conditions which an applicant for naturalisation must meet:
Cantons can impose further requirements which are complementary to the federal requirements.
Simplified naturalisation.
Confederation.
Foreigners in the following categories may apply for simplified naturalisation:
Simplified naturalisation by virtue of marriage.
A person married to a Swiss citizen may apply for Swiss citizenship by facilitated naturalisation after living in Switzerland for five years and having been married for at least three years. No language test is required, but one must show the following:
Children from the person's previous relationships (but not same-sex couples) are given citizenship along with the partner.
It is also possible for the spouse of a Swiss citizen to apply for facilitated naturalisation while residing overseas after the following:
Spouses acquiring Swiss citizenship by facilitated naturalisation will acquire the citizenship of the place and canton of origin of their Swiss spouse.
Simplified naturalisation for third generation immigrants.
The federal constitution declares that the Confederation will facilitate the naturalisation of third generation immigrants (Art. 38 §3 part a). Legislation has yet to be introduced describing the precise requirements for an application for facilitated naturalisation under article 38 §3 part a.
Canton of Vaud.
The Canton of Vaud legislated in 2004 to allow for second-generation foreigners to acquire Swiss nationality more easily under the following conditions:
The 2004 law also facilitates the naturalisation of foreigners of the 3rd generation under the following conditions:
Demographics.
The yearly rate of naturalisation has quintupled over the 1990s and 2000s, from roughly 9,000 to 45,000 naturalisations per year.
Relative to the population of resident foreigners, this amounts to an increase from 8% in 1990 to 27% in 2007, or relative to the number of Swiss citizens from 0.16% in 1990 to 0.73% in 2007.
Reacquisition of Swiss nationality.
Foreigners in the following category can apply to have their nationality restored:
Formal conditions:
Loss of Swiss citizenship.
Loss due to cessation of paternity.
A child whose Swiss citizenship depends on paternal links loses citizenship when those are cut.
Loss due to adoption.
A Swiss child adopted by foreign parents is considered to have lost Swiss citizenship; if the adoption is subsequently annulled, the loss of nationality is retroactively invalidated.
Loss due to birth abroad.
A Swiss citizen born abroad to at least one Swiss parent and holding at least one other nationality loses Swiss citizenship at age 25 if:
Equally, the child of a person who loses Swiss nationality in this manner also loses Swiss nationality.
Exceptionally, a person who has been prevented, against their will, from taking the necessary actions to retain Swiss citizenship may undertake the required actions within a delay of 1 year following the cessation of such hindrances.
Triple citizenship level within Swiss citizenship.
Each municipality in Switzerland maintains its own registry of citizens, which is separate from the registry of people living in the municipality. Many Swiss citizens do not live in their place of origin; therefore, they are often required by the municipality in which they live to get a certificate of citizenship ("acte d'origine/Heimatschein/atto d'origine") from their place of origin. The constitution forbids discrimination based on one's place of origin, with the exception of bourgeoisies.
Dual nationality.
According to the Federal Office for Migration, there has been no restriction on multiple citizenship in Switzerland since 1 January 1992. Thus, foreigners who acquire Swiss citizenship and Swiss citizens who voluntarily acquire another citizenship keep their previous citizenship (subject to the laws of the other country). An estimated 60% of Swiss nationals living abroad in 1998 were multiple citizens.
Since many nationality laws now allow both parents to transmit their nationality to their common child (and not only the father, as used to be often the case), many children automatically acquire multiple citizenship at birth. This is especially prevalent in Switzerland, since a relatively high proportion of the population holds a foreign passport (up to 54% in Geneva and 20% nationally). However, the Federal Office for Migration specially notes that this has not resulted in any significant practical problems. Military service, the most likely problem to arise, is usually done in the country where the applicant resides at the time of conscription.
Even though Swiss nationality law permits multiple citizenship, a Swiss national who also holds another country's citizenship may be required to renounce a citizenship, if that foreign country's nationality law forbids such multiple citizenship.
Political discussions and referendums about Swiss citizenship in Switzerland in recent years.
Swiss citizenship laws have been widely debated over recent years. In comparison to other nationality laws, access to Swiss citizenship is relatively narrow and restricted, and several modifications to widen access to Swiss citizenship via constitutional initiatives and referendums have been proposed. The referendums on the matter – held in 1983, 1994, and 2004 – were all rejected by Swiss voters. In particular, during the referendum held in September 2004, Swiss voters rejected proposals to give some long-resident Swiss-born persons aged between 14 and 24 the right to apply for "facilitated" naturalisation (which bypasses cantonal and municipal requirements) and grant automatic Swiss citizenship to persons born in Switzerland with a parent also born in Switzerland.
While minimal requirements for obtaining Swiss citizenship by naturalisation are set at the federal level, Swiss cantons and municipalities are free to introduce more stringent requirements. Some municipalities had previously had no procedure for allowing naturalisations, effectively rendering it impossible, such as in La Chaux in the Canton of Vaud. In 1999, the municipality of Emmen and the canton of Lucerne began using referendums to decide the outcome of naturalisation requests. The practice was ruled unconstitutional by the Supreme Court in July 2003. A referendum directed at legalizing this practice was rejected on 1 June 2008.
Rights and obligations of Swiss citizens.
Swiss citizens are entitled to
Male Swiss citizens, including dual citizens, can be required to perform military service or civilian service (women can do it voluntarily). Male citizens who do not complete their military service or who do not do civilian service must pay a supplementary tax. Swiss citizens are not allowed to work for a foreign (non-Swiss) military, unless they are a citizen of – and are resident in – the country in question. The Swiss Guards of the Vatican State are regarded as police, not as an army.
Travel freedom of Swiss citizens.
Visa requirements for Swiss citizens are administrative entry restrictions by the authorities of other states placed on citizens of Switzerland. In May 2018, Swiss citizens had visa-free or visa-on-arrival access to 185 countries and territories, ranking the Swiss passport 5th in the world according to the Visa Restrictions Index.
The Swiss nationality is ranked ninth, together with Ireland, in The Quality of Nationality Index (QNI). This index differs from the Visa Restrictions Index, which focuses on external factors including travel freedom. The QNI considers, in addition, to travel freedom on internal factors such as peace & stability, economic strength, and human development as well.