A NATO Stock Number, or National Stock Number (NSN) as it is known in the US, is a 13-digit numeric code used by the NATO military alliance, identifying all the 'standardized material items of supply' as they have been recognized by all member states of NATO. Pursuant to the NATO Standardization Agreements, the NSN has come to be used in all treaty countries. However, many countries that use the NSN program are not members of NATO (e.g. Japan, Australia and New Zealand). A two-digit Material Management Aggregation Code (MMAC) suffix may also be appended, to denote asset end use but it is not considered part of the NSN.
In the United Kingdom it is known as a Domestic Management Code (DMC). In France it is known as a Numéro de Nomenclature OTAN (NNO), or "NATO Identification Number". In Spanish-speaking countries it is known as a Número Nacional de Efecto (NNE), or "National Item Number".
An item having an NSN is said to be "stock-listed".
Structure
The NATO Stock Number consists of the NATO Supply Class (NSC or FSC) and the National Item Identification Number (NIIN). However the NIIN alone uniquely identifies the item, the FSC merely adds context by indicating the general classification of the item. The format of an NSN might be described as follows:
abcd-ef-ghi-jklm
Each element, a through m, was originally intended to be a single decimal digit. As inventories grew in complexity, element g became alphanumeric, beginning with uppercase A for certain newly added items. By 2000, uppercase C was in use.
Federal Supply Classification Group (FSCG)
The initial subgroup, abcd, is the Federal Supply Classification Group (FSCG) or National Supply Classification Group (NSCG). In theory, similar items would always have closely related numbers in this section of the NSN, no matter how the section is referred to. As the number of items has steadily increased and the system has become more complicated, it has not always been possible to keep similarity in numbers when the items are similar.comtinue...
National Item Identification Number (NIIN)
The nine digits, ef-ghi-jklm, comprise the NIIN (National Item Identification Number). This format improves readability but is optional as NIINs are often listed without hyphens.
The first two digits of the NIIN (the ef pair) are used to record which country was the first to codify the item—which one first recognized it as an important item of supply. This is generally the country of origin, meaning the country of final manufacture. The formal name of the field is CC for Country Code or NCB, because NCB also stands for National Codification Bureau. The NCB is the organisation, typically a government agency, in charge of maintaining the NCS database within a given country. The other seven characters are a non-significant identification code. Following are the NCB codes:
As the list shows, users of the NCS system not only include the 30 NATO member countries, but the 33 NATO-sponsored countries as well. It is also grouped into tiers indicating participation and access.
Tier 1 Nations (Algeria, Bosnia-Herzegovina, Brunei Darussalam, Chile, Colombia, Egypt, Georgia, Oman, Pakistan, Peru, Qatar, Saudi Arabia, South Africa, Thailand) Nation has access to unclassified NSN data. There is a one-way data exchange and it does not participate in technical NCS management.
Tier 2 Nations (Argentina, Australia, Austria, Brazil, Columbia, India, Indonesia, Israel, Japan, Jordan, Republic of Korea, Malaysia, Morocco, New Zealand, Serbia, Singapore, Sweden, Ukraine, United Arab Emirates) Nation has a codification system that has been certified as fully NCS compliant. There is a two-way data exchange and participation in technical NCS management.
Tier 3 Nations (Albania, Belgium, Bulgaria, Canada, Croatia, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Italy, Latvia, Lithuania, Luxembourg, Montenegro, Netherlands, Republic of North Macedonia, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Turkey, the United Kingdom, and the United States): Nation is a NATO member and has a full membership in the NATO Codification Bureau (NCB).