Resident registration number

In the Republic of Korea, a 'resident registration number (RRN)' (Korean: 주민등록번호 (romanized: Jumin Deungrok Beonho), Hanja: 住民登錄番號) is a 13-digit number issued to all residents of South Korea regardless of nationality. Similar to national identification numbers in other countries, it is used to identify people in various private transactions such as banking and employment. It is also used extensively for online identification purposes. Foreigners (except those affiliated with the U.S. military) receive an alien registration number upon registration with a city office, which serves as a substitute for the "resident" registration number on their alien registration card.

Every South Korean citizen within a month of their 17th birthday registers their fingerprint at the government local office and is issued the Resident Registration Card that contains their name, registration number, home address, fingerprint and picture.

The resident registration number consists of 13 digits, with each digit providing specific information, as illustrated below:

The first six digits signify the person's date of birth; for example, a person born on September 1, 1946, such as former President Roh Moo-Hyun , would have 460901 as the first six digits of his RRN.

S, the seventh digit, indicates the sex and the century in which the person was born:

bbbb, the eighth through eleventh digits, signifies place of birth on Korean citizens' cards. In the registration numbers of foreign residents, these number indicate which agency issued the registration number.

Every citizen of South Korea automatically receives a resident registration number with seventh digit of 9, 0, 1, 2, 3, or 4 (indicating as a Korean citizen) when one's parents register one's birth in South Korea. Therefore, foreign born citizens of South Korea do not automatically receive a resident registration number even after they obtain their Korean passports through Korean diplomatic offices. Foreign born citizens can have resident registration numbers with seventh digit of 9, 0, 1, 2, 3, or 4 by visiting South Korea and registering their births, but the South Korean Immigration Bureau considered foreign born citizens with overseas permanent resident status as foreigners and did not issue a resident registration number with seventh digit of 9, 0, 1, 2, 3, or 4 to foreign born citizens with overseas permanent resident status. Since a resident registration number with seventh digit of 9, 0, 1, 2, 3, or 4 is required to exercise rights of citizenship, citizens without a resident registration number were not guaranteed rights of citizenship except diplomatic protection.

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Wikipedia