Sri Lankan citizenship law is principally governed under the principle of ius sanguinis. Citizenship can also be obtained by birth if at least one of the parents is a Sri Lankan citizen or if the person was born in Sri Lanka where neither of the parents was at the time of his birth a citizen of Sri Lanka but subsequently at least one parent has obtained Sri Lankan citizenship.
Citizenship can be obtained through marriage by the spouse or the widow/widower of a citizen of Sri Lanka by descent or registration. Persons who have rendered distinguished public service or are eminent in professional, commercial, industrial, or agricultural life, may be granted citizenship through naturalisation. Citizenship can also be obtained by foreign investors and professionals who have made a substantial contribution to economic, social and cultural development, through naturalisation where the person was under a Resident Guest Scheme for a period of 5 years.
Foreign nationals who acquire Sri Lankan citizenship are not required to renounce their original nationality. However, according to the law in Sri Lanka, prior to acquiring another citizenship, a Sri Lankan citizen has to obtain a declaration from the Minister, otherwise the citizenship will be lost. This method is known as the mechanism of retention of citizenship. Another option for attaining dual citizenship is the resumption of citizenship for citizens who have lost their citizenship as a result of obtaining citizenship in another country. Those who wish to retain/resume their Sri Lankan citizenship can do so by applying through one of the seven categories. These include the age category, property category, assets category, fixed deposit of Rs. 2.5 million or above category, fixed deposit of USD 25,000 or above category, Treasury Bond (TB) or Inward Investment Account (IIA) valued at USD 25,000 for minimum 3 years period category, and Spouse of an applicant or an unmarried child under the age of 22 of the applicant category.