National identification number

A national identification number is used by the governments of many countries as a means of tracking their citizens, permanent residents, and temporary residents for the purposes of work, taxation, government benefits, health care, and other governmentally-related functions. Sometimes, the number will appear on an identity card issued by a country.

The ways in which such a system is implemented is dependent on the country, but in most cases, a citizen is issued a number at birth or when they reach a legal age (typically the age of 18). Non-citizens are issued such numbers when they enter the country.

Many countries issue such numbers ostensibly for a singular purpose, but over time, they become a de facto national identification number. For example, the United States originally developed its Social Security Number system as a means of disbursing Social Security benefits. However, due to functionality creep, the number has become utilized for other purposes to the point where it is almost essential to have one in order to, among other things, open a bank account or obtain a credit card.

National identification numbers in different countries

Argentina

In Argentina the only nationally issued identification is the DNI, Documento Nacional de Identidad (National Identity Document). It's a number not related to anything in particular about the person (except for immigrants who get assigned numbers starting at 90.000.000). It's assigned at birth by the Registro Nacional de las Personas (National Registry for People), but parents need to sign up their children, and because of this there are many people, especially the poor, who don't have a DNI.

This ID is required for most things, for example applying for a credit, opening a bank account, and even for voting. Law requires a person to show his DNI when using a credit card. Prior to the DNI the LC (Libreta Cívica, for women), and LE (Libreta de Enrolamiento, for men) were used. This was later unified in the DNI.

For taxpaying purposes, the CUIT and CUIL (Código Único de Identificación Tributaria, Unique Code for Taxpaying Identification and Código Único de Identificación Laboral, Unique Code for Laboral Identification). An example of the ID is 20-10563145-8. It's based on the DNI and appends 2 numbers at the beginning and one at the end. For example, 20 and 23 for men, 27 for women, and one control digit at the end. Employees have a CUIL (assigned at the moment the DNI is created), and employers have a CUIT. The first two digits to identify the CUIT for companies are for instance: 30 or 33. If a person decides to open a company of its own, his CUIL usually becomes his CUIT. The CUIT was needed because a different identification is required for companies, who can't be identified by a DNI number.

Australia

In Australia there is no universal identifying number for individuals. The closest to universal at present are:

• Medicare card number, for health services
• Tax File Number (TFN), for tax matters
• Driver's License, for general matters

The Australia Card proposal would have created a universal number for Australian citizens and permanent residents. That proposal was abandoned in 1987, however the Access Card (which was proposed in 2005) may adopt a similar approach.

Austria

In Austria there are two universal schemes to identify individuals:

Social Security Number (SSN) The Austrian SSN is a well-established identifier, and would identify in theory every Austrian citizen. Its format is a 3-digit serial number, a checksum digit and the birth date in an DDMMYY-notation. Because it contains the birth date, it is considered a privacy-sensitive number. For that reason, its use is restricted by law to certain areas of health care, social security, taxes, education and other administrative areas. That makes it unusable as a general person identifier, but pervasive enough to make it a threat to data privacy. There are some practical disadvantages, too. It is being assigned without proper legitimating hence there are duplicates. It does not cover people without social security, although these are few in Austria. Some immigrates without papers from their homeland have their birth date changed (after understanding the pros and cons of being under a certain age). In general the SSN is a quite reliable identifier, but not good enough for classes of application that require qualified identification.

Sector-Specific Personal Identifier (ssPIN) The ssPIN tries to do away with all problems of the SSN. Its legal foundation is the Austrian E-Government Act, and it is derived from the Central Register of Residents (CRR). Its specification is related with the Austrian Citizen Card. Its computation (specification) is a 2 stage process: The CCR ID is encoded into the Source Identification Number (Soure PIN) with a symmetrical crypto-function. This is again one-way encoded into the ssPIN per sector of governmental activity. For the storage of SourcePINs is not limited to citizen cards, and an application cannot convert a ssPIN from one sector to the ssPIN from applications of other sectors, the link-up of data of different sectors by PINs is constricted. However, there is a legal exception to this rule: applications may query for and store ssPINs from other sectors if they are encrypten in a way, that makes them only usable in the target application. This enables application to communicate across sectors.

Sample values:

• CCR-ID: 000247681888 (12-digit)
• SourcePIN: MDEyMzQ1Njc4OWFiY2RlZg== (24 Bytes base64)
• ssPIN(BW): MswQO/UhO5RG+nR+klaOTsVY+CU= (28 Bytes base64)
  • BW (Bauen + Wohnen) is the public sector related to "construction and habitation".
  • There are currently approx. 30 sectors like health, taxes, statistics, security, etc.)

Belgium

In Belgium every citizen has a National Number, which is created by using the citizen's date of birth (encoded in six digits), followed by a serial number (three digits) and a checksum (two digits). The serial number is used so that men get the odd numbers, while women get the even numbers; thus, there can be only 500 men or women on each day.

The national number is unique to each person and in that capacity used by most government institutions; however, because one can immediately read the date of birth and the sex of the numbers' holder and because it is the key in most government databases (including that of the tax administration, the social security, and others), it is considered a privacy-sensitive number. For that reason, although it is put on the identity card by default, with the old ID cards a citizen could request that this would not be done. With the newer Digital ID cards that Belgium is rolling out now, however, this is no longer possible, since the National Number is used as the serial number for the private cryptography keys on the card.

Brazil

In Brazil there are two different systems. The first one, the Registro Geral (RG) is a number associated to the official ID card. Oddly, although the ID cards are supposedly national, the RG numbers are assigned by the states and a few other organizations, such as the armed forces. So, not only is it possible for one to have the same RG number as a person from other state (which is usually dealt with by specifying the state which issued the ID card), but it's also possible to (legally) have more than one RG, from different states.

The other system, the Cadastro de Pessoas Físicas (CPF) is federal and supposedly unique (barring fraud), but it was created originally only for purposes of taxation (a related system is used for companies). One, the other or both numbers are required for many common tasks in Brazil, such as opening bank accounts or getting a driver's license. Generally speaking, the RG system is more widespread (many poor people, who have no bank accounts, never get around to registering for a CPF), but its practical shortcomings have led to debate about merging both systems into a new one, which would be based around the CPF.

Bulgaria

Main article: Uniform civil number

In Bulgaria every citizen has a Uniform Citizenship Number (Bulgarian: Единен граждански номер, Edinen grazhdanski nomer, usually abbreviated as ЕГН e-ge-ne, EGN), which is created by using the citizen's date of birth (encoded in six digits in the form YYMMDD), followed by a serial number (three digits) and a checksum (one digit). The serial number shows the gender: odd numbers are used for females and even numbers for males.

This system was introduced in the early 80's when there was a sizable number of living people born in the late 19th century. For them the century was encoded in the month digits adding 20 (e.g. an EGN of 952324XXXX denotes a person born on 24th March 1895). 40 is added to denote a persons is born in the 21st century (e.g. 054907XXXX denotes a person born at 7th September 2005). Most probably 60 will be added in the future for persons born in the 22nd century and 80 for ones from the 23rd century. Thus the EGN system can hold unique numbers for persons born in a span of time of a half millennium.

The national number is presumably unique to each person and in that capacity used by most government institutions.

Canada

Main article: Social Insurance Number

The use of the Social Insurance Number (SIN) as a "de facto" ID number has not become as widespread. There are only certain specified instances where a person must provide a SIN (namely for tax or retirement benefit related issues). In other instances, a business is free to ask for a person's SIN, but they cannot deny service on the basis that the person can't or won't provide one.

People's Republic of China

In the PRC, an ID card is mandatory for all citizens who are over 16 years old. The ID number has 18 digits and is in the format RRRRRRYYYYMMDDSSSC, which is the sole and exclusive identification code for the holder (an old ID card only has 15 digits in the format RRRRRRYYMMDDIII). RRRRRR is a standard code for the political division where the holder is born (county or a district of a city), YYYYMMDD is the birth date of the holder, and SSS is a sequential code for distinguishing people with identical birthdates and birthplaces. The sequential code is odd for males and even for females. The final character, C, is a checksum value over the first 17 digits. To calculate the checksum, each digit in order is multiplied by a weight in the ordered set [ 7 9 10 5 8 4 2 1 6 3 7 9 10 5 8 4 2 ] and summed together. The sum modulus 11 is used as an index into the ordered set [ 1 0 X 9 8 7 6 5 4 3 2 ], with the first index being zero. The indexed value is the checksum digit. In 15 digit IDs, III is an identification number created through certain mathematical methods (the last digit might be an English letter, such as X). The ID card is used for residential registration, army enrollment registration, registration of marriage/divorce, going abroad, taking part in various national exams, and other social or civil matters.

Republic of China (Taiwan)

In the ROC, an ID card is mandatory for all citizens who are over 14 years old. The ID card was uniformly numbered since 1965. The currnet ID number has 10 digits. The first digit is one capital Latin alphabet and is followed by nine Arabic numerals. The alphabet records the card holder's first location of household registration, which is usually where s/he was born. The digit that follows the alphabet records the card holder's gender. "1" is for males and "2" is for females. The last digit is a checksum value.

Colombia

In Colombia, each person, is issued with a basic ID card during childhood (Tarjeta de Identidad). The ID number includes the date of birth and a short serial number. Upon reaching the age of 18, every citizen is reissued a citizenship card (Cédula de Ciudadanía), and the ID number on it is used and required on all instances, public and private.

Croatia

Main article: Unique Master Citizen Number

Croatia inherited JMBG system (Croatian: Jedinstveni matični broj građana), translated as Unique Master Citizen Number, after the splitting of Yugoslavia in 1991. Though there were initiatives to replace JMBG with unique Croatian citizen ID numbers, JMBG is so well rooted into Croatian administration and businesses that this change never took place.

Czech Republic

In the Czech Republic the same system, inherited from former Czechoslovakia, is used as in the Slovak Republic. It is described below.

Denmark

Main article: Personal identification number (Denmark)

A Personal Identification Number is used in dealings with public agencies, from health care to the tax authorities. It is also commonly used as a customer number in banks and insurance companies.

Estonia

In Estonia, a Personal identification code (Estonian: isikukood (IK)) is defined as a number formed on the basis of the sex and date of birth of a person which allows the specific identification of the person and extensively used by government and other systems where identification is required, as well as by digital signatures using the nation ID-card and its associated certificates. An Estonian Personal identification code consists of 11 digits, generally given without any whitespace or other delimiters. The form is GYYMMDDSSSC, where G shows sex and century of birth (odd number male, even number female, 1-2 19. century, 3-4 20. century, 5-6 21. century), SSS is a serial number separating persons born on the same date and C a checksum.

Finland

In Finland, the personal identification number (Finnish: henkilötunnus (HETU), Swedish: Personbeteckning), formerly known as sosiaaliturvatunnus (SOTU) Social Security number) is used for identifying the citizens in many government and civilian systems. It uses the form DDMMYYCZZZQ, where DDMMYY is the date of birth, C is the century identification sign (+ for the 19th century, - for the 20th and A for the 21st), ZZZ is the personal identification number (even for females, odd for males) and Q is a checksum character. For example, a valid henkilötunnus is 311280-999J.

The checksum character is calculated thus: Take the birth date and person number, and join them into one 9-digit number x. Let n = x mod 31. Then the checksum letter is the (n+1)th character from this string: "0123456789ABCDEFHJKLMNPRSTUVWXY".

The use of the personal ID number is regulated, and requesting is legally restricted. Often it is needed for government transactions. It is also treated much like a proof of identity in many contexts, such as health care, so it is advisable not to make it public. Employers often track salaries using the number. The number is given shortly after birth, and it is also possible for foreigners to get one for purposes of employment registration.

The number is shown in all forms of valid identification:

• National ID card
• Electronic national ID card (with a chip)
• Driver's license (old A6-size and new credit card-size)
• Passport

France

Main article: INSEE code

In France, the INSEE code is used as a social insurance number, a national identification number, for taxation purposes, for employment, etc. It was originally invented under the Vichy regime.

Greece

In Greece, there are a number of national identification numbers.

• The standard identity card, which has the format A-99999, which is issued on all Greek citizens at the age of 14 or so.
• The tax id (AFM - ΑΦΜ - Αριθμός Φορολογικού Μητρώου - Tax Registry Number), which is used by citizens and companies for tax reasons. It has 9 digits, the last one is a check digit.

Germany

In Germany, there is no national identification number, nor any kind of central database. Most people have a social insurance number and a tax file number, but those are only used for their specific purpose.

For some time, the West German government intended to create a 12-digit personal identification number (Personenkennzeichen, PKZ) for all citizens, registered alien residents on its territory, as well as for all non-resident Nazi victims entitled to compensation payments. The system, which was to be implemented by the 1973 federal law on civil registry, was eventually rejected in 1976, when the Bundestag found the concept of an identification system for the entire population to be incompatible with the existing legal framework.

In East Germany, a similar system named Personenkennzahl (PKZ) was set up in 1970 and remained in use until the state ceased to exist in 1990.

Hong Kong

In Hong Kong, an ID Card (HKID) is mandatory for all citizens aged over 11 and long-term residents. HKID cards contain the bearer's HKID number, of which the standard format is X123456(A). X represents one or two letters of the alphabet. The numerals may represent any Arabic number. A is the check digit, which has 11 possible values from 0 to 9 and A. The letters and numbers are not assigned arbitrarily.

Iceland

All living Icelanders, as well as all foreign citizens with permanent residence in Iceland, have a personal identification number (Icelandic: kennitala) identifying them in the National Registry. This number is composed of 10 digits, of which the first six are the individual's birth date in the format DDMMYY. The next two digits are chosen at random when the kennitala is allocated, the 9th digit is a check digit, and the last digit indicates the century in which the individual was born (for instance, '9' for the period 1900–1999, or '0' for the period 2000-2099). An example would be 120174-3389, the person being born the twelfth of January 1974. While similar, all-inclusive personal registries exist in other countries, the use of the national registry is unusually extensive in Iceland. For example, some video rentals register their customers using the registry identification numbers. It is worth noting that the completeness of the National Registry eliminates any need for censuses to be performed.

India

In India, there is no formal national identification scheme or number. Various schemes had been proposed but were never implemented. The closest India has come to this is the Permanent account number (PAN), issued by the Income Tax Office, for purposes of tracking income and income taxes. It has now gained use as a means of identification for activities like getting a phone connection. The MNIC project appears to be a strong contender for nation-wide implementation with pilots underway in 13 states, with specific focus on covering the border regions.

Ireland

Main article: Personal Public Service Number

In the Republic of Ireland the Personal Public Service Number (PPS No) is increasingly gaining the characteristics of a national identification number as it is used for a widening variety of public services - although it is stated that it is not a national identifier and its use is defined by law[1]. The PPS No. is in the basic form of 1234567A and is unique to every person.

For certain public services the collection or retention of numbers of the general public is not allowed, thus Garda Siochána (Irish police) is only given an exemption for its own employees or other people defined under the Immigration Act, 2003 - the latter who are people who are not European Union nationals. Similarly the Irish Defence Forces may only collect and retain the number for their own employees.

The number is also used in the private sector, but is limited to a few procedures that lawfully required the production of a number, for transactions with public services and in this regard the private sector will be acting as the agent of a public body entitled to collect and retain the number. Thus, for instance, students who attend college or university will routinely have their number (or other personal data) collected at registration - this will then be sent to Department for Social and Family Affairs to ensure that a student is not simulataneously claiming social welfare. Banks may collect the number for the administration of accounts that give interest or tax reliefs which the state funds, through the Revenue Commissioners. A bank may not use the number as a customer identification number.

Israel

An Identity Number (Hebrew: Mispar Zehut) is issued to all Israeli citizens at birth by the Ministry of the Interior. It is comprised of nine digits: a one-digit prefix, seven digits, and a final check digit. Blocks of numbers are distributed to hospitals, and individual numbers are issued to babies upon discharge from hospital. Temporary residents (category A-5) are assigned a number when they receive temporary resident status.

An Identity Card, (Hebrew: Teudat Zehut), bearing an Identity Number, is issued to all residents over 16 years old who have legal temporary or permanent residence status, including non-citizens.

Italy

In Italy, the fiscal code (Italian Wikipedia: Codice fiscale) is issued to Italians at birth. It is in the format "SSSNNNYYMDDZZZZX", where: SSS are the first three consonants in the family name (the first vowel and then an X are used if there are not enough consonants); NNN is the first name, of which the first, third and fourth consonants are used—exceptions are handled as in family names; YY are the last digits of the birth year; M is the letter for the month of birth—letters are used in alphabetical order, but the letters I, J, K, N, O, Q and letters after T are not used (thus, January is A and October is R); DD is the day of the month of birth—in order to differentiate between genders, 40 is added to the day of birth for women (thus a woman born on May 3 has ...E43...); ZZZZ is an area code specific to the municipality where the person was born—country-wide codes are used for foreign countries; X is a parity character as calculated by adding together characters in the even and odd positions, and dividing them by 26. Numerical values are used for letters in even positions according to their alphabetical order. Characters in odd positions have different values. A letter is then used which corresponds to the value of the remainder of the division in the alphabet. An exception algorithm exists in case of perfectly matching codes for two persons. Issuance of the code is centralized to the Ministry of Treasure. The fiscal code uniquely identifies an Italian citizen or permanently resident alien, and is thus used. However, since it can be calculated from personal information (whether real, or not), it is not generally regarded as an extremely reserved piece of information, nor as official proof of identity/existence of an individual.

Macau

Macau has a similar ID-card policy to that in Hong Kong.

Malaysia

See also: MyKad

In Malaysia, a 12-digit number (format: YYMMDD-SS-###G, since 1991) known as the Identification Card number (IC) is issued to citizens and permanent residents on a MyKad. Prior to January 1 2004, a separate social security (SOCSO) number (also the old IC number in format 'S#########', S denotes state of birth or country of origin (alphabet or number), # is a 9-digit serial number) was used for social security-related affairs.

The first group of numbers (YYMMDD) are the date of birth. The second group of numbers (SS) represents the place of birth of the holder - the states (01-13), the federal territories (14-16) or the country of origin (60-85)[2]. The last group of numbers (###G) is a serial number in an unidentified pattern which is randomly generated. The last digit (G) is an odd number for a male, while an even number is given for a female.

Netherlands

Dutch Wikipedia: nl:Sofi-nummer

In the Netherlands the most commonly used ID number is the SoFi nummer. The abbreviation SoFi stands for Social & Fiscal. It is also printed on driving licenses, passports and international ID cards, under the header Personal Number.

New Zealand

In New Zealand, an Inland Revenue Department (IRD) number is issued by the IRD to every taxpayer (a natural or juristic person), and is needed with all dealings with the IRD. It must be given to any employer or bank responsible for charging withholding tax, and to apply for or use a student loan. Driver's licences carry a unique number, often recorded when providing them as identification.

The social security and student support services of the Ministry of Social Development (Work and Income, and StudyLink) issue a Work and Income client number, assigned at the occurrence of a person's first contact with either service. A general letter of enquiry about a service appears to be sufficient for one to be logged and may be assigned without the letter writer's knowledge.

A National Health Index (NHI) number is assigned to all newborn New Zealanders at birth, and those who use a health and disability support service that do not already have one.

The Ministry of Education also issues a National Student Number (NSN) which is the key to its database of qualifications. Students receive a their NSN from the Ministry their education provider if they do not have one already. Those who previously held an NQF number from the New Zealand Qualifications Authority use this as their NSN.

Though there has been a plan for a National ID Card (dropped after three months), the small population means a name and date of birth can usually uniquely identify someone, though identity theft is easily possible when two people share a name and birthdate.

Norway

The Norwegian 'birth number' (Norwegian: fødselsnummer, from fødselsdato (birth date) and personnummer (person(al) number)); inaccurately often called the personnummer) has eleven digits. The first six give the date of birth in the format DDMMYY, while the last five are the actual personnummer. The first three numbers of the personal number (i.e., the seventh to ninth in the full number) are called the individual number; a number between 000 and 499 indicates that the person was born between 1900 and 1999, a number between 500 and 750 indicates that the person was born between 1850 and 1899. A number between 500 and 999 indicates that the person is born between 2000 and 2049, this means that people born after the year 1999 and before the year 1900 might get the same personal number (but the year part of the birth number indicates what century the person is born in, a year less than or equal to 49 means 21st century (2000s), while a year greater than or equal to 50 means 19th century (1800s)). This means that this system needs to be refined before the year 2049. The numbers between 750 and 999 was previously reserved for special purposes such as adoptions from abroad and immigrants. The third number in the personal number (the ninth in the birth number) indicates gender; males have odd numbers while females have even numbers. The last two digits of the personal number and birth number is two check digits. The first check digit is calculated using Modulo 11 of the 9 first digits, while the last check digit is calculated using Modulo 11 of the 10 first digits (including the second last check digit). The first check digit is weighted against the numbers 3, 7, 6, 1, 8, 9, 4, 5, 2 while the second check digit is weighted against the numbers 5, 4, 3, 2, 7, 6, 5, 4, 3, 2.

Pakistan

Since the 1960s, Pakistan has issued been issuing National Identity Card (commonly know by the acronym, NIC) numbers to its citizens. These numbers are assigned at birth when the parents complete the child's birth registration form (B-Form), and then a National Identity Card (NIC) with the same number is issued at the age of 18. Until, 2001 NIC numbers were 11 digits long. In 2001-2002, the National Database Reorginization Authority (NADRA), started issuing 13 digit NIC numbers along with their new biometric ID cards. The first 5 digits are based on the applicants locality, the next 7 are serial numbers, and the last digit is a check digit. The old numbers are invalid as of 2004.

Every citizen is required to have a NIC number, and the number is required for many activities such as paying taxes, opening a bank account, getting a utility connection (phone, cell phone, gas, electricity), etc... However, since a majority of births in the country are not registered, and a large quantity of Pakistanis do not conduct any of the activities described above, most do not have ID cards. Obtaining an NIC card also costs 100 rupees(almost the average daily income), and this inevitably reduces the amount of people who can afford it. By some estimates, less than 20% of Pakistanis have the new ID cards.

Poland

Main article: PESEL

In Poland, a Powszechny Elektroniczny System Ewidencji Ludności (PESEL) number is mandatory for all permanent residents of Poland and for temporary residents living in Poland for over 2 months. It has the form YYMMDDZZZXQ, where YYMMDD is the date of birth (with century encoded in month field), ZZZ is the personal identification number, X denotes sex (even for females, odd for males) and Q is a parity number.

Romania

In Romania every citizen has a Personal Numeric Code (Cod Numeric Personal - CNP), which is created by using the citizen's gender and century of birth (1/3/5/7/9 for male or 2/4/6/8 for female), date of birth (encoded in six digits), the country zone (encoded on 2 digits, from 1 to 52 or 99), followed by a serial number (encoded on 3 digits) and a checksum (encoded on one digit) Ex: GYYMMDDCCNNNC.

The first digit encods the gender and the century of birth as follows:

• 1 - male born between 1900 and 1999
• 2 - female born between 1900 and 1999
• 3 - male born between 1800 and 1899
• 4 - female born between 1800 and 1899
• 5 - male born between 2000 and 2099
• 6 - female born between 2000 and 2099
• 7 - male resident
• 8 - female resident

The country zone is the code of the county in alphabetical order. For Bucharest the code is 4 followed by the sector number. The checksum is calculated as following: every digit from CNP is multiplied with the digit with the same index from the number 279146358279, the results are sumed up and then divided by 11. If the rest is 10 then the checksum digit is 1, otherwise is the rest itself.

Singapore

In Singapore there is something called NRIC (National Registration Identity Card), which is given to all the Singapore Citizens and Permanent Residence. Foreigners working on work permit or student visa are issued FIN - Foreign Identification Number, and a separate card is issued to them.

Slovakia

In Slovakia there are currently two kinds of National identification number in use. The first one is the Birth Number (Slovak: Rodné číslo (RČ)), is issued at birth by the civic records authority (Slovak: matrika) and recorded on the birth certificate. Its format is YYMMDD/XXXX with YYMMDD being the date of birth and XXXX being a semi-unique identifier. For females, the month of the date of birth is advanced by 50. Full number(identification number - YYMMDDXXXX) must be divideable by 11. As this system does not provide a unique identifier (the numbers are repeated every century) it may be replaced by a meaningless identifier in the near future. The second system is the Citizen's Identification Card Number (Slovak: Číslo občianskeho preukazu (ČOP)) which is in the form AA XXXXXX (A-alphabetic, X-numeric) and is used on current ID cards. Identification Cards are issued by the state authorities (police) at 15 years of age for every citizen. In contrast to the Birth Number, this identifier can change over the citizen's lifetime if a new card is issued, for various reasons such as expiration, loss or change of residence. The ID number is used, among other things, for voter registration (because of the domicile record verification provided by the ID). A similar system, with both types of identification numbers, is used in the Czech Republic as well.

South Africa

South African Identity Document

In the Republic of South Africa, every citizen can be issued an Identity Document from the age of 16 years. This passport-size document contains only 8 pages - the first page containing the national identification number (also in barcoded format), name of bearer, district or country of birth, as well as a photograph of the bearer. The other pages are used for recording of voting participation, a page for driver's license information (although it is no longer used since the introduction of credit card type licenses), as well as pages for fire arms licenses. The Identity Document is not used for travel purposes (a separate passport is issued), and mainly serves as proof of identification. Some authorities may accept the driver's license as proof of identity, but the Identity Document is the only universally accepted form of identification. The ID number is a 13-digit number of which the first 6 digits are the date of birth in the form YYMMDD. The next digit is a gender indicator (0-4 denoting female, 5-9 denoting male) followed by a 3 digit sequence code. The last 3 digits start with 0 if the person is an SA citizen, otherwise with 1. The second last number is usually either 8 or 9 and the last digit is a control digit. During the apartheid era these last three digits also denoted race.

See also:

• Guide to South African ID no. validation

South Korea

Main article: Resident registration number (South Korea)

In South Korea, every Korean resident is assigned a Resident's Registration Number(주민등록번호), which has the form 000000‒0000000. The first seven digits have his/her birthday and gender, where the first six digits are in the format YYMMDD and the seventh digit is determined by the century and the gender as follows:

	Male	Female
1800s	9	0
1900s	1	2
2000s	3	4

(For example, a male citizen who was born in 27 May 2001 is assigned the number 010527‒3******, and a female citizen which was born in 24 March 1975 is assigned the number 750324‒2******.)

The next 4 digits mean the region of his/her birth registration, and the next 1 digit is a serial number of registration within the date and the region. The last digit is a check digit.

Spain

In Spain, all Spanish citizens are issued with a National Identity Document (Spanish: Documento Nacional de Identidad (DNI)), with a unique number, in the format 0000000-A (where 0 is a digit and A is a letter). Foreign nationals are issued with a similar identity card, with a number in the format X-0000000-A (again, 0 is a digit, A is a letter, and the X is a literal X), called a NIE (Número de Identificación de Extranjeros, Foreigner's Identity Number). The numbers are used as identification for almost all purposes.

Sweden

Main article: Personal identity number (Sweden)

In Sweden a Personal Identity Number (Swedish: personnummer) is used in dealings with public agencies, from health care to the tax authorities. It is also commonly used as a customer number in banks and insurance companies. The number uses ten digits where the first six give the birth date in YYMMDD format. The Swedish personnummer was probably the first of its kind when it was introduced on the 1st of January 1947.

Thailand

In Thailand, the Popluation Identification Code has been issued by the Department of Provincial Administration of the Ministry of Interior since 1976. It consists of a 13-digit string in the format N-NNNN-NNNNN-NN-N, which is assigned at birth or upon receiving citizenship. The first digit signifies type of citizenship, the second to fifth the office where the number was issued, the sixth to twelfth are group and sequence numbers, and the last digit acts as a check digit.

United Kingdom

Main article: National Insurance § The National Insurance number

A National Insurance number, generally called an NI Number (NINO), is mainly used to administer state benefits, but has not gained the ubiquity of its US equivalent. The number is stylised as LL NN NN NN L, for example AA 01 23 44 B.

Each baby born in the UK is issued a National Health Service Number, taking the form NNN-NNN-NNNN, for example 122-762-9255 (the last number being a check digit, not correct in the example [3]). They were formerly of the style "LLLNNL NNN", for example KWB91M 342, which continued patterns used in World War II identity cards. However, since National Health Numbers often change when moving to a different part of the country and having to change General Practitioners, the ratio is more often more one person - many numbers than one person - one number. The National Programme for Information Technology (NPfIT) has also shown that one person can have many numbers.

United States

Main article: Social Security number (United States)

A Social Security number is a nine digit number resembling "123-45-1234" which is issued to an individual by the Social Security Administration of the government of the United States. Up until the 1980s, people often had no Social Security number until the age of about 15 or 16, since they were used for tax purposes and those under that age seldom had remunerative employment. In the 1980s, the law was altered so that persons without Social Security numbers could not be claimed as dependents on tax returns. Many parents now apply for Social Security numbers for their children as soon as the children are born. When a baby is born in a hospital, hospital staff generally offer to help the parents apply for Social Security by filling out and submitting the application for the parents. It was never intended to be a national identification number, and card inscriptions originally claimed for years that the Social Security card and number were not to be used for identification purposes, though it is widely used, and abused, as one today.

Former Yugoslav republics

Main article: Unique Master Citizen Number

In former Yugoslavia and subsequent countries, each citizen has a Unique Master Citizen Number (Serbian: Jedinstveni Matični Broj Građana (JMBG), Macedonian: Единствен матичен број на граѓанинот (ЕМБГ) ).