Singaporean nationality law details the conditions by which a person holds Singapore nationality. The primary law governing nationality requirements is the Constitution of Singapore, which came into force on 9 August 1965.
Individuals born to at least one Singaporean parent are typically automatically citizens at birth, regardless of where the birth occurred. Birth in Singapore by itself does not make a child eligible for citizenship. Foreign nationals may become Singaporean citizens after completing a residence requirement (normally 10 years) and renouncing any previous nationalities. Holding another nationality concurrently is generally disallowed and there are many paths for a Singaporean citizen to lose their citizenship should they acquire another nationality.
Singapore was briefly a constituent part of Malaysia and local residents were Malaysian citizens from 1963 to 1965. Prior to this, Singapore was a colony of the British Empire and municipal citizens were British subjects. Although the country gained independence in 1965 and Singaporeans no longer hold Malaysian nor British nationality, they continue to hold favoured status in the United Kingdom; as Commonwealth citizens, Singaporeans are eligible to vote in UK elections and serve in public office there.
History
Modern Singapore was founded in 1819 and soon after merged with Penang and Malacca to form the Straits Settlements in 1826. After their incorporation as Crown dominions in 1858, British nationality law applied to the Straits Settlements, as was the case elsewhere in the British Empire. Singaporeans and all other imperial citizens were British subjects; any person born in Singapore, the United Kingdom, or anywhere else within Crown dominions was a natural-born British subject.
In the rest of British Malaya outside of the Straits Settlements, local Malay rulers were given limited autonomy in exchange for accepting British suzerainty. Subjects of the rulers in the Federated Malay States and Unfederated Malay States were considered British protected persons. Although Britain held jurisdiction in all of British Malaya, domestic law treated the Malay states as foreign territory. British protected persons were treated as aliens in the United Kingdom, but both British subjects and protected persons could be issued British passports. Protected persons could not travel to the UK without first requesting permission, but were afforded the same consular protection as British subjects when travelling outside of the Empire. A person with connections both to directly governed portions of British Malaya and one of the Malay states could be a British subject and British protected person simultaneously.
Singaporean citizenship was first granted in 1957. Singapore Citizenship Ordinance 1957 which commenced on 1 November 1957 provided Singaporean citizenship to all people who were born in Singapore (except children of diplomats and enemy aliens). People who were born in the Federation of Malaya or citizens of the United Kingdom and Colonies who had been resident for two years, and others who had been resident for eight years were able to register or naturalise as Singaporean citizen. When Singapore gained internal self-government in 1959, Singapore became an independent Commonwealth country for the purpose of British nationality law. From then on, Singaporean passports had the unusual nationality status of "British subject: citizen of the State of Singapore" instead of the usual "British subject: citizen of the United Kingdom and Colonies". There are treaties signed by the United Kingdom during this period specifically mention this unusual nationality status.
In 1963, Singaporean nationality law was incorporated into the new Constitution of the State of Singapore. The constitution repealed the 1957 Ordinance, and all persons who were citizens as of 16 September 1963 by virtue of the Ordinance continued to be Singaporean citizens. All Singaporean citizens became Malaysian citizens on 16 September 1963 upon Singapore's merger with Malaysia on that date. Malaysian nationality law provided that Singaporean citizenship to continue to exist as a subnational citizenship. Singaporean citizenship continued to be legislated by the Legislative Assembly of Singapore, subject to the approval of the Parliament of Malaysia. Singaporean citizenship was inseparable from Malaysian citizenship; it was not possible to have Singaporean citizenship without having Malaysian citizenship.
Upon Singapore's secession from Malaysia on 9 August 1965, Malaysian citizenship was withdrawn from Singaporean citizens.