What is the International Securities Identification Number (ISIN)

The International Securities Identification Number (ISIN) is a code that uniquely identifies a specific securities issue. The organization that allocates ISINs in any particular country is the country's respective National Numbering Agency (NNA).

BREAKING DOWN International Securities Identification Number (ISIN)

All internationally traded securities issuers are urged to use the ISIN numbering scheme, which is now the accepted standard by virtually all countries. The United States and Canada primarily use a similar scheme, known as a CUSIP number.

ISIN codes have a total of 12 characters, consisting of both letters and numbers. These include the country in which the issuing company is headquartered (first two digits), along with a number specific to the security (middle nine digits), and a final character, which acts as a check. An example of an ISIN number for a US company’s stock certificate could look like: US-000402625-0 (dashes incorporated for simplicity). On the other hand, a theoretical Namibian company could have an ISIN, which appears as: NA-000K0VF05-4. The middle nine digits of the ISIN are computer-generated in a complex formula. These are critical in helping protect against counterfeiting and forgery.

An ISIN is administered by the relevant National Numbering Agency. In the United States this is the CUSIP Service Bureau. Established in 1964, the CUSIP Service Bureau was created to improve country-wide standards for the financial services industry. Today, it continues to enforce its numbering system via a board of trustees.

International Organization for Standardization (ISO) 6166 currently defines an ISIN’s structure. Currently, an ISIN can be attributed to most forms of securities, including (but not limited to) equity shares, units, and/or depositary receipts; debt instruments, including bonds, stripped coupons and principal amounts, and T-bills; rights and warrants; derivatives; commodities and currencies.