NIIN - NATO Item Identification Number

The unique segment (last 9 alphanumeric characters) of a NATO Stock Number (NSN) that never changes for an Item of Supply in the NATO Supply Catalog. While NSNs may change, the NIIN is always constant. Each of the nine characters of the NIIN can be a letter character or a digit. It is convention to quote a NSN in UPPERCASE. Some alphabetic characters are excluded from use to avoid reading confusion with digits.

NIIN Format
NIIN NATO Item Identification Number
NIIN (NATO Item Identification Number)

NIIN Lookup

Search for NIINs in NMCRL

What is a NIIN?

A NIIN is the last 9 digits of a NSN. A NATO Item Identification Number. A National Item Identification Number. The NIIN is the unique identifier of a NATO Stock Number (NSN) as the supply classification for an item can change over time.

What are NATO Item Identification Numbers?

The NATO Item Identification Number is the last 9 digits of a NSN which is unique to an item over its entire lifetime. While the item's supply class may change over time changing the NSN, the NIIN remains the same. A single supply item may therefore have multiple NSNs but only one NSN is active and current at any time.

What are National Item Identification Numbers?

A National Item Identification Number is the last 9 digits of a NSN which is unique and unchanging for an item over its lifetime in the military nsn database. The term National Item Identification Number (NIIN Number) has long been replaced by NATO Item Identification Number yet the definition remains the same.

NATO Item Identification Number (NIIN)

NATO Stock Numbers comprise three data segments:

  1. The supply classification class (where the first two digits identify the supply classification group)
  2. The national codification bureau (NCB)
  3. The supply item number (SIN)
The supply classification class can change over time as the NATO Catalog is re-organized by moving supply items from one class to another. The NIIN or Item Identification Number is the last nine-digits of the NSN combining the second two segments of the NSN, the NCB and the SIN. The NIIN number remains constant and unique to any supply item in the NATO Catalog.

Understanding that the supply class of an item can change provides that any supply item can only have one NIIN but can have multiple NSNs. At any point in time, a Supply Item can only have one active NSN. A system of supercession is present in the NATO Stock Number database system allowing for any NSN to be related to historical NSNs for the same item of supply by NIIN together with the date of change and reason.

It becomes apparent that any producer or consumer of Items of Supply referenced by NSN must monitor the NATO NSN Database for changes in supply classes of relevant items and update their documentation as required to remain current as well as accomodating users unaware of these changes.

NIIN Part Number

NIIN are unique to a stock number and stock numbers are unique by their physical characteristics allowing multiple manufacturers or sources of supply per NIIN. Each source of supply is cataloged into the NATO Supply Database (NMCRL) as the source's part number as a cross-reference to the NIIN. The NIIN number is sometimes quoted as the NIIN Part Number as it is a unique identifier to the item yet manufacturer independent.