ISIN (International Securities Identification Number)

An International Securities Identification Number (ISIN) is a unique 12-character alphanumeric code assigned to every financial security — including equity shares, bonds, mutual fund units, ETFs, and government securities — to uniquely identify it across global markets and depository systems. The ISIN structure follows the ISO 6166 standard: the first two characters denote the country code (IN for India), followed by nine alphanumeric characters identifying the specific security, and a final check digit for verification. In India, ISINs are assigned by NSDL (National Securities Depository Limited) for securities held in NSDL's depository system and by CDSL (Central Depository Services Limited) for securities in CDSL's system — though each security has only one ISIN regardless of which depository holds it. ISINs are essential for seamless cross-border trade and settlement — foreign portfolio investors (FPIs) use ISINs to identify and trade Indian securities, and India's international bond issuances (Masala Bonds, sovereign bonds) are identified by ISINs recognised by international clearing systems like Euroclear and Clearstream.