Singapore

(1) There shall be a status known as citizen of Singapore.
(2) The status of a citizen of Singapore may be acquired —
(a) by birth;
(b) by descent;
(c) by registration or, before the commencement of this Constitution, by enrolment; or
(d) by naturalisation. (Art. 120)

(1) Subject to this Article, every person born in Singapore after 16th September 1963 shall be a citizen of Singapore by birth.
(2) A person shall not be a citizen of Singapore by virtue of clause (1) if at the time of his birth —
(a) his father, not being a citizen of Singapore, possessed such immunity from suit and legal process as is accorded to an envoy of a sovereign power accredited to the President;
(b) his father was an enemy alien and the birth occurred in a place then under the occupation of the enemy; or
(c) Neither of his parents was a citizen of Singapore.
(3) Notwithstanding clause (2)(c), the Government may, where it considers it just and fair and having regard to all the circumstances prevailing at the time of the application, confer citizenship upon a person born in Singapore. (Art. 121)

(1) Subject to clauses (2) and (3), a person born outside Singapore after 16th September 1963 shall be a citizen of Singapore by descent if, at the time of his birth —
(a) where the person is born before the date of commencement of section 7 of the Constitution of the Republic of Singapore (Amendment) Act 2004, his father is a citizen of Singapore, by birth or registration; and(b) where the person is born on or after the date of commencement of section 7 of the Constitution of the Republic of Singapore (Amendment) Act 2004, either his father or mother is a citizen of Singapore, by birth, registration or descent.
(2) A person born outside Singapore shall not be a citizen of Singapore by descent by virtue of clause (1) unless —
(a) his birth is registered in the prescribed manner at the Registry of Citizens or at a diplomatic or consular mission of Singapore within one year, or such longer period as the Government permits, after its occurrence; and
(b) he would not acquire the citizenship of the country in which he was born by reason of his birth in that country where —
(i) in the case of a person born before the date of commencement of section 7 of the Constitution of the Republic of Singapore (Amendment) Act 2004, his father is a citizen of Singapore by registration at the time of his birth; or
(ii) In the case of a person born on or after the date of commencement of section 7 of the Constitution of the Republic of Singapore (Amendment) Act 2004, either his father or mother is a citizen of Singapore by registration at the time of his birth.
(3) Without prejudice to clause (2), a person born outside Singapore of a father or mother who is a citizen by descent at the time of his birth shall not be a citizen of Singapore by descent by virtue of clause (1) unless the parent who is the citizen by descent has lawfully resided in Singapore —
(a) for a period of, or for periods amounting in the aggregate to, not less than 5 years before that person’s birth; or
(b) for a period of, or for periods amounting in the aggregate to, not less than 2 years during the period of 5 years immediately preceding that person’s birth.
… (Art. 122)

(1) Subject to the provisions of this Constitution, any person resident in Singapore of or over the age of 21 years may, on application being made therefor in the prescribed form, be registered as a citizen of Singapore if he satisfies the Government that he —
(a) is of good character;
(b) has resided in Singapore throughout the 12 months immediately preceding the date of his application;(c) has during the 12 years immediately preceding the date of his application resided in Singapore for periods amounting in the aggregate to not less than 10 years:
Provided that the Government may exempt any applicant from compliance with this paragraph —
(i) where such applicant has during the 6 years immediately preceding the date of his application resided in Singapore for periods amounting in the aggregate to not less than 5 years; or
(ii) where in any special case the Government considers fit to confer citizenship upon such applicant;
(d) intends to reside permanently in Singapore; and
(e) has an elementary knowledge of one of the following languages, namely, Malay, English, Mandarin and Tamil:
Provided that the Government may exempt an applicant who has attained the age of 45 years or who is deaf or dumb from compliance with this paragraph.
(2) Subject to the provisions of this Constitution, any woman who is married to a citizen of Singapore may, on making application therefor in the prescribed manner, be registered as a citizen of Singapore if she satisfies the Government —
(a) that she has resided continuously in Singapore for a period of not less than 2 years immediately preceding the date of the application;
(b) that she intends to reside permanently in Singapore; and
(c) that she is of good character. (Art. 123)

(1) Subject to clause (4), the Government may, upon application made by any person of or over the age of 21 years who is not a citizen of Singapore, grant a certificate of naturalisation to that person if the Government is satisfied —
(a) that he has resided in Singapore for the required periods and intends, if the certificate is granted, to do so permanently;
(b) that he is of good character; and
(c) that he has an adequate knowledge of the national language.
… (Art. 127)

(1) Any citizen of Singapore of or over the age of 21 years and of sound mind who is also or is about to become a citizen of another country may renounce his citizenship of Singapore by declaration registered by the Government, and shall upon such registration cease to be a citizen of Singapore.
(2) The Government may withhold the registration of a declaration under this Article —
(a) if the declaration is made during any war in which Singapore is engaged; or
(b) if the declaration is made by a person subject to the Enlistment Act (Cap. 93) unless he has —
(i) discharged his liability for full-time service under section 12 of that Act;
(ii) rendered at least 3 years of operationally ready national service under section 13 of that Act in lieu of such full-time service; or
(iii) complied with such conditions as may be determined by the Government.
(3) This Article applies to a woman under the age of 21 years who has been married as it applies to a person of or over that age. (Art. 128)

(1) A citizen of Singapore who is a citizen by registration or by naturalisation shall cease to be such a citizen if he is deprived of his citizenship by an order of the Government made in accordance with this Article.
...
(6) The Government may, by order, deprive of her citizenship any woman who is a citizen of Singapore by registration under Article 123(2) if the Government is satisfied that the marriage by virtue of which she was registered has been dissolved, otherwise than by death, within the period of 2 years beginning with the date of the marriage.
… (Art. 129)

Where a person has —
(a) renounced his citizenship; or
(b) been deprived of his citizenship under Article 129(2)(a) or 134(1)(a),
the Government may, by order, deprive of his citizenship any child of that person under the age of 21 years who has been registered as a citizen of Singapore pursuant to this Constitution and was so registered as being the child of that person or of that person’s wife or husband. (Art. 130)

(1) The Government may, by order, deprive a citizen of Singapore of his citizenship if the Government is satisfied that —
(a) he has, while of or over the age of 18 years, at any time after 6th April 1960 acquired by registration, naturalisation or other voluntary and formal act (other than marriage) the citizenship of any country outside Singapore or having so acquired such citizenship before the age of 18 years continues to retain it after that age; or
(b) the citizen, being a woman who is a citizen of Singapore by registration under Article 123(2), has acquired the citizenship of any country outside Singapore by virtue of her marriage to a person who is not a citizen of Singapore.
… (Art. 134)

(1) Where a person has been deprived of his citizenship or his enrolment as a citizen has been cancelled under the provisions of this Part, the Government may, by order, deprive of his citizenship or, as the case may be, cancel the enrolment of any child of that person under the age of 21 years who has been registered or enrolled as a citizen under the provisions of this Constitution or the Singapore Citizenship Ordinance 1957 (Ord. 35 of 1957) and was so registered or enrolled as being the child of that person or of that person’s wife or husband.
(2) No person shall be deprived of his citizenship under clause (1) unless the Government is satisfied that it is not conducive to the public good that he should continue to be a citizen; and no person shall be deprived of his citizenship under clause (1) if the Government is satisfied that as a result of such deprivation he would not be a citizen of any country. (Art. 137)

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6. Any notice to be given by the Minister to any person under Article 133(1) may be sent to that person at his last known address or, in the case of a person under the age of 18 years (not being a married woman) to his parent or guardian at the last known address of the parent or guardian; and if an address at which the notice may be sent to any person under this paragraph is not known and cannot after reasonable inquiry be ascertained, the notice may be given by publication in the Gazette.
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15. (1) For the purposes of Part X, references to a person’s father or to his parent or to one of his parents shall, in relation to a person who is illegitimate, be construed as references to his mother.
… (Third Schedule)