What is a National Stock Number (NSN)?

The North Atlantic Treaty Organization (NATO) Codification System (NCS) provides standards for the use of a common stock identification system throughout the NATO alliance. Subsequently, its use has spread to other countries around the world. The advantage of having international partners using the same supply identification standards for their defense products as is used by the U.S. is that it allows for the exchange of parts and support equipment between participating nations in a coalition.

To achieve the three NCS objectives of (1) increasing the efficiency and effectiveness of logistics operations, (2) facilitating data handling, and (3) minimizing costs to user nations, it is essential that each item of supply be assigned a unique name, classification, identification, and a NATO or National Stock Number (NSN). Countries that participate in the NCS follow common standards and techniques to assign NATO stock numbers to items of supply in their defense inventory. The national codification bureau within each country centrally assigns their national NSNs. The National Codification Bureau (NCB) for the U.S. is DLA Information Operations. The assignment of an NSN fixes the identity of each distinctive item of supply. All NSNs are uniform in composition, length, and structure. Each National Stock Number is a thirteen-digit code whose first four digits are the Federal Supply Classification, followed by a code for the assigning country’s national codification bureau and a sequential serial number.

The FLIS is the U.S. Government Department of War (DoW) database of all the National Stock Numbers, associated part numbers, manufacturers’ identification, and management information that the DoW utilizes and manages. The FLIS also contains unique packaging, hazardous materials, and freight information, and each item’s most recent procurement information. The FLIS lists active stock numbered and part numbered items in the Federal inventory.