Vietnam’s personal identification number, shown on the Citizen ID card, is a 12-digit numeric code centrally managed nationwide by the Ministry of Public Security. Each citizen is assigned one unique number for life, from birth until death, and it is never duplicated.
The 12-digit number is structured into several information groups:
First three digits: Province, city, or national code
These digits indicate the place where the citizen’s birth was registered.
Provincial and municipal codes range from 001 to 096, corresponding to Vietnam’s 63 centrally governed provinces and cities. For example, Hanoi is coded 001, Son La 014, Da Nang 048, and Ho Chi Minh City 079.
Fourth digit: Century of birth and gender code
This digit combines the century in which the person was born with their gender, using the following rules:
People born in the 20th century, from 1900 to 1999: male 0, female 1.
People born in the 21st century, from 2000 to 2099: male 2, female 3.
People born in the 22nd century, from 2100 to 2199: male 4, female 5.
People born in the 23rd century, from 2200 to 2299: male 6, female 7.
People born in the 24th century, from 2300 to 2399: male 8, female 9.
Fifth and sixth digits: Year of birth
These digits represent the last two numbers of the citizen’s birth year.
For example, someone born in 1987 would have 87, while someone born in 2020 would have 20.
Last six digits: Random serial number
This is a random sequence from 000001 to 999999, ensuring that each personal identification number remains unique even when individuals share the same place of birth, year of birth, and gender.
Important notes on format and continuity
Under the old system, Vietnam used both 9-digit and 12-digit identity numbers. When a 9-digit ID was replaced with the new 12-digit Citizen ID, the identification number changed entirely. However, people who already had a 12-digit ID or a barcode-based Citizen ID retained the same number when switching to the chip-based card.
The 12-digit personal identification number is permanent and does not change, even if a citizen moves residence or replaces a lost card.
Under the 2023 Law on Identification, effective from 01/07/2024, the card name was shortened from “Citizen ID” to simply “ID Card.” The 12-digit personal identification number, however, remains unchanged in structure and function.
