A CNP (Cod Numeric Personal, or Personal Numeric Code) is the unique 13-digit identifier assigned by Romanian authorities to an individual. It is used to identify people in official records and in interactions involving public administration, taxation, healthcare, employment, banking, and other regulated services.
The CNP is often compared with a national identification or social security number, but it is Romania’s own identification system and should not be treated as interchangeable with identifiers issued by other countries.
What does a Romanian CNP look like?
A CNP contains exactly 13 digits and follows this general structure:
S YY MM DD JJ NNN C
| Part | Length | Meaning |
|---|---|---|
S |
1 digit | Encodes the person’s sex and, for common values, the century of birth |
YY MM DD |
6 digits | Date of birth in year-month-day format |
JJ |
2 digits | Administrative or allocation code |
NNN |
3 digits | Sequence number used to distinguish people with otherwise similar data |
C |
1 digit | Checksum used to detect typing and formatting errors |
How to interpret the digits
First digit: sex and century
For Romanian citizens, the most common first-digit values are:
- 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
Other values may be used for foreign residents or special administrative cases. The first digit should therefore not be interpreted without considering the person’s official status and documents.
Digits 2–7: date of birth
The next six digits encode the date of birth as YYMMDD. For example, the pattern 991231 represents 31 December 1999 when paired with a first digit indicating the correct century.
A valid format must also represent a real calendar date. Values such as an impossible month, 31 February, or 29 February in a non-leap year are invalid.
Digits 8–9: administrative code
These digits have traditionally represented a county, Bucharest sector, or another allocation code associated with the registration process. The code should not always be treated as reliable proof of a person’s current address, residence, or place of origin.
For CNPs generated through Romania’s Integrated Information System for Civil Status Records (SIIEASC), the Ministry of Internal Affairs has confirmed the use of the unique code 70 in this part of the CNP. This means that newer CNPs issued through that system should not be interpreted using the older county-by-county allocation table. For historical county and Bucharest sector codes, see the guide to county codes in a CNP.
Digits 10–12: sequence number
The three-digit sequence helps distinguish individuals who share the same encoded date and allocation characteristics. It does not function as a separate document number.
Final digit: checksum
The last digit is calculated from the first 12 digits. Each digit is multiplied by the corresponding digit in the fixed control key:
279146358279
The products are added and the total is divided by 11. The remainder normally becomes the control digit; if the remainder is 10, the control digit is 1.
This calculation can identify many typing errors, but a correct checksum does not prove that the CNP was officially issued or belongs to the person presenting it.
How to check whether a CNP is valid
A basic structural check should confirm that:
- the value contains exactly 13 digits;
- the first digit is permitted for the relevant category;
- the encoded birth date is a real date;
- the administrative and sequence fields follow applicable rules;
- the final checksum is correct.
You can perform these checks with the CNP validator. Structural validation only shows that a number follows the expected mathematical format. Confirmation that a CNP exists or belongs to a particular person requires an authorized official source.
Where is the CNP used?
A CNP may be requested when a person needs to be identified accurately for a legitimate purpose, including:
- identity and civil-status records;
- tax and social insurance administration;
- employment and payroll reporting;
- public healthcare and insurance services;
- banking, credit, and legally required identity checks;
- contracts or official applications where identification is necessary.
The CNP is different from the series and number printed on a Romanian identity card. The identity document number identifies the document itself, while the CNP identifies the person and generally remains associated with them even when the document is replaced.
Who receives a CNP?
Romanian citizens normally receive a CNP through the civil registration process. Romanian authorities may also assign one to foreign citizens or residents when required by their legal or administrative status.
A person should use only the CNP officially assigned by the competent authority. A mathematically valid number created for testing is not an official identity and must not be used in real documents, contracts, accounts, or transactions.
Is a CNP confidential?
A CNP is personal data with a general identification function and can be used to identify a person precisely. Organizations that process a CNP should have a defined purpose and an appropriate legal basis under data-protection law, while also applying measures such as access restrictions, data minimization, appropriate retention periods, and protection against unauthorized disclosure.
- Do not publish a complete CNP online or send it through unsecured channels.
- Mask unnecessary digits in screenshots, support tickets, and internal reports.
- Do not collect a CNP merely because it is convenient.
- Use test values rather than real identities in software development.
- If a CNP may have been misused, contact the relevant institution and consider reporting suspected fraud to the competent authorities.
Possessing someone’s CNP alone does not automatically authorize access to their records or allow another person to act on their behalf.