NSn

NSN stands for National Stock Number, a 13-digit numeric code used to identify standardized material items of supply within the NATO Codification System. The NSN is assigned to items that are standardized across multiple users, enabling a common reference for procurement, stocking, and logistics among NATO members and many partner nations, as well as various U.S. and allied government agencies.

Structure and format: The 13 digits comprise the Federal Supply Class (FSC) followed by the National Item Identification Number (NIIN). The FSC is a four-digit code that groups items by their primary use (for example, electrical equipment or clothing). The NIIN is nine digits long and consists of a two-digit National Codification Bureau (NCB) code and a seven-digit item number. Together, the FSC and NIIN form a unique NSN for the item.

Purpose and usage: The NSN provides interoperable identification across catalogs, requisitions, contracts, and inventories. It is used in military and government supply chains to facilitate ordering, stocking, maintenance, and asset management. The system is managed through national codification bureaus and the NATO Support and Procurement Agency, with each item codified once and referenced by all participating nations.

Notes: An NSN identifies an item version rather than a specific manufacturer; suppliers may have their own part numbers that correspond to the same NSN. When items are modified or replaced, new NSNs may be issued to reflect the updated item.

See also: NATO Codification System; NIIN; Federal Supply Class.